kcgg kceg service manual

Service Manual

Types KCGG 122, 142,KCEG 112, 142, 152, 242 and

KCEU 142, 242Overcurrent and Directional Overcurrent

Relays

HANDLING OF ELECTRONIC EQUIPMENT

A person's normal movements can easily generate electrostatic potentials of several thousand volts.Discharge of these voltages into semiconductor devices when handling electronic circuits can causeserious damage, which often may not be immediately apparent but the reliability of the circuit will havebeen reduced.

The electronic circuits of ALSTOM T&D Protection & Control Ltd products are immune to the relevant levelsof electrostatic discharge when housed in their cases. Do not expose them to the risk of damage bywithdrawing modules unnecessarily.

Each module incorporates the highest practicable protection for its semiconductor devices. However, if itbecomes necessary to withdraw a module, the following precautions should be taken to preserve the highreliability and long life for which the equipment has been designed and manufactured.

1. Before removing a module, ensure that you are at the same electrostatic potential as the equipmentby touching the case.

2. Handle the module by its front-plate, frame, or edges of the printed circuit board.Avoid touching the electronic components, printed circuit track or connectors.

3. Do not pass the module to any person without first ensuring that you are both at the sameelectrostatic potential. Shaking hands achieves equipotential.

4. Place the module on an antistatic surface, or on a conducting surface which is at the samepotential as yourself.

5. Store or transport the module in a conductive bag.

More information on safe working procedures for all electronic equipment can be found in BS5783 andIEC 60147-0F.

If you are making measurements on the internal electronic circuitry of an equipment in service, it ispreferable that you are earthed to the case with a conductive wrist strap.Wrist straps should have a resistance to ground between 500k – 10M ohms. If a wrist strap is notavailable, you should maintain regular contact with the case to prevent the build up of static.Instrumentation which may be used for making measurements should be earthed to the case wheneverpossible.

ALSTOM T&D Protection & Control Ltd strongly recommends that detailed investigations on the electroniccircuitry, or modification work, should be carried out in a Special Handling Area such as described inBS5783 or IEC 60147-0F.

Service Manual


KCEU 142, 242Overcurrent and

Directional Overcurrent Relays


KCEU 142, 242Overcurrent and

Directional Overcurrent Relays

Service Manual

R8551D

SERVICE MANUAL R8551DKCGG 122, 142 ContentsKCEG 112, 142, 152, 242KCEU 142, 242

SAFETY SECTION

THIS MUST BE READ BEFORE ANY WORK IS CARRIED OUT ON THE RELAY

CHAPTER 1 INTRODUCTION

CHAPTER 2 HANDLING AND INSTALLATION

CHAPTER 3 RELAY DESCRIPTION

CHAPTER 4 APPLICATION OF PROTECTION FUNCTIONS

CHAPTER 5 MEASUREMENT AND RECORDS

CHAPTER 6 SERIAL COMMUNICATIONS

CHAPTER 7 TECHNICAL DATA

CHAPTER 8 COMMISSIONING

APPENDIX 1 RELAY CHARACTERISTIC CURVES

APPENDIX 2 LOGIC DIAGRAMS

APPENDIX 3 CONNECTION DIAGRAMS

APPENDIX 4 COMMISSIONING TEST RECORD

Page 2

SAFETY SECTION

This Safety Section should be read before commencing any work onthe equipment.

Health and safety

The information in the Safety Section of the product documentation is intended toensure that products are properly installed and handled in order to maintain themin a safe condition. It is assumed that everyone who will be associated with theequipment will be familiar with the contents of the Safety Section.

Explanation of symbols and labels

The meaning of symbols and labels which may be used on the equipment or in theproduct documentation, is given below.

Caution: refer to product documentation Caution: risk of electric shock

Protective/safety *earth terminal

Functional *earth terminal.Note: this symbol may also be used for a protective/safety earth terminal if that terminal is part of aterminal block or sub-assembly eg. power supply.

*Note: The term earth used throughout the product documentation is the directequivalent of the North American term ground.

Installing, Commissioning and ServicingEquipment connections

Personnel undertaking installation, commissioning or servicing work on thisequipment should be aware of the correct working procedures to ensure safety.The product documentation should be consulted before installing, commissioning orservicing the equipment.

Terminals exposed during installation, commissioning and maintenance maypresent a hazardous voltage unless the equipment is electrically isolated.

If there is unlocked access to the rear of the equipment, care should be taken by allpersonnel to avoid electric shock or energy hazards.

Voltage and current connections should be made using insulated crimpterminations to ensure that terminal block insulation requirements are maintainedfor safety. To ensure that wires are correctly terminated, the correct crimp terminaland tool for the wire size should be used.

Page 3

Before energising the equipment it must be earthed using the protective earthterminal, or the appropriate termination of the supply plug in the case of plugconnected equipment. Omitting or disconnecting the equipment earth may cause asafety hazard.

The recommended minimum earth wire size is 2.5 mm2, unless otherwise stated inthe technical data section of the product documentation.

Before energising the equipment, the following should be checked:

Voltage rating and polarity;

CT circuit rating and integrity of connections;

Protective fuse rating;

Integrity of earth connection (where applicable)

Equipment operating conditions

The equipment should be operated within the specified electrical andenvironmental limits.

Current transformer circuits

Do not open the secondary circuit of a live CT since the high voltage producedmay be lethal to personnel and could damage insulation.

External resistors

Where external resistors are fitted to relays, these may present a risk of electricshock or burns, if touched.

Battery replacement

Where internal batteries are fitted they should be replaced with the recommendedtype and be installed with the correct polarity, to avoid possible damage to theequipment.

Insulation and dielectric strength testing

Insulation testing may leave capacitors charged up to a hazardous voltage. At theend of each part of the test, the voltage should be gradually reduced to zero, todischarge capacitors, before the test leads are disconnected.

Insertion of modules and pcb cards

These must not be inserted into or withdrawn from equipment whilst it is energised,since this may result in damage.

Fibre optic communication

Where fibre optic communication devices are fitted, these should not be vieweddirectly. Optical power meters should be used to determine the operation or signallevel of the device.

Page 4

Older ProductsElectrical adjustments

Equipments which require direct physical adjustments to their operating mechanismto change current or voltage settings, should have the electrical power removedbefore making the change, to avoid any risk of electric shock.

Mechanical adjustments

The electrical power to the relay contacts should be removed before checking anymechanical settings, to avoid any risk of electric shock.

Draw out case relays

Removal of the cover on equipment incorporating electromechanical operatingelements, may expose hazardous live parts such as relay contacts.

Insertion and withdrawal of extender cards

When using an extender card, this should not be inserted or withdrawn from theequipment whilst it is energised. This is to avoid possible shock or damagehazards. Hazardous live voltages may be accessible on the extender card.

Insertion and withdrawal of heavy current test plugs

When using a heavy current test plug, CT shorting links must be in place beforeinsertion or removal, to avoid potentially lethal voltages.

Decommissioning and Disposal

Decommissioning: The auxiliary supply circuit in the relay may includecapacitors across the supply or to earth. To avoid electricshock or energy hazards, after completely isolating thesupplies to the relay (both poles of any dc supply), thecapacitors should be safely discharged via the externalterminals prior to decommissioning.

Disposal: It is recommended that incineration and disposal to watercourses is avoided. The product should be disposed of in asafe manner. Any products containing batteries should havethem removed before disposal, taking precautions to avoidshort circuits. Particular regulations within the country ofoperation, may apply to the disposal of lithium batteries.

Page 5

Technical SpecificationsProtective fuse rating

The recommended maximum rating of the external protective fuse for thisequipment is 16A, Red Spot type or equivalent, unless otherwise stated in thetechnical data section of the product documentation.

Insulation class: IEC 61010-1: 1990/A2: 1995 This equipment requires aClass I protective (safety) earthEN 61010-1: 1993/A2: 1995 connection to ensure userClass I safety.

Installation IEC 61010-1: 1990/A2: 1995 Distribution level, fixedCategory Category III installation. Equipment in(Overvoltage): EN 61010-1: 1993/A2: 1995 this category is qualification

Category III tested at 5kV peak,1.2/50µs, 500Ω, 0.5J,between all supply circuitsand earth and also betweenindependent circuits.

Environment: IEC 61010-1: 1990/A2: 1995 Compliance is demonstratedPollution degree 2 by reference to genericEN 61010-1: 1993/A2: 1995 safety standards.Pollution degree 2

Product safety: 73/23/EEC Compliance with theEuropean Commission LowVoltage Directive.

EN 61010-1: 1993/A2: 1995 Compliance is demonstratedEN 60950: 1992/A11: 1997 by reference to generic

safety standards.

Page 6



RelaysService Manual

Chapter 1Introduction

SERVICE MANUAL R8551DKCGG 122, 142, Chapter 1KCEG 112, 142, 152, 242, ContentsKCEU 142, 242

1. INTRODUCTION 12. USING THE MANUAL 13. AN INTRODUCTION TO K RELAYS 24. MODELS AVAILABLE 35. AVAILABILITY OF MAIN FEATURES 4

SERVICE MANUAL R8551DKCGG 122, 142, Chapter 1KCEG 112, 142, 152, 242, Page 1 of 4KCEU 142, 242

Section 1. INTRODUCTION

The K Range of overcurrent and directional overcurrent relays has beenrationalised and additional features have been added to the individual relays towiden their application. Some menu cell locations have changed to accommodatethe new features and so setting files that have been generated for the series 1relays to suit particular applications may need some small modification before theycan be used with the new K Range series 2. However, the menu locations formeasured values and other data that is accessed by SCADA equipment retain theiroriginal locations. Hence the changes should be transparent to mostcommunication interfaces that may have been developed.

Manual R8501 should be used for K Range series 1 relays.

This manual details the menu, functions and logic for the K Range series 2 relays.

Section 2. USING THE MANUAL

This manual provides a description of the K Range series 2 overcurrent anddirectional overcurrent range of protection relays. It is intended to guide the userthrough application, installation, setting and commissioning of the relays.

The manual has the following format:

Chapter 1. Introduction

An introduction on how to use this manual and a generalintroduction to the relays covered by the manual.

Chapter 2. Handling and installation

Precautions to be taken when handling electronic equipment

Chapter 3. Relay description

A detailed description of features that are common to allK Range series 2 relays.

Chapter 4. Application of protection functions

An introduction to the applications of the relays and specialfeatures provided.

Chapter 5. Measurements and records

How to customise the measurements and use the recording features.

Chapter 6. Serial communications

Hints on using the serial communication feature.

Chapter 7. Technical data

Comprehensive details on the ratings, setting ranges andspecifications etc.

Chapter 8. Commissioning

A guide to commissioning, problem solving and maintenance.

Appendix Appendices include relay characteristic curves, logic diagrams,connection diagrams and commissioning test records.


Section 3. AN INTRODUCTION TO K RELAYS

The K Range of protection relays brings numerical technology to the successfulMidos range of protection relays. Fully compatible with the existing designs andsharing the same modular housing concept, the relays offer more comprehensiveprotection for demanding applications.

Each relay includes an extensive range of control and data gathering functions toprovide a completely integrated system of protection, control, instrumentation, datalogging, fault, event and disturbance recording. The relays have a user-friendly 32character liquid crystal display (LCD) with 4 push buttons which allow menunavigation and setting changes. Also, by utilising the simple 2-wire communicationlink, all of the relay functions can be read, reset and changed on demand from alocal or remote personal computer (PC) loaded with the relevant software.

With enhanced versatility, reduced maintenance requirements and low burdens,K Range relays provide a more advanced solution to power system protection.The K Range series 2 relays have new features that are additional to those foundon series 1 relays. The additional functions include:

Protection thermal, underfrequency, broken conductor detection, rectifierprotection and improved undervoltage

Measurement thermal ammeters, single phase W and VAR

Logic improved logic flexibility

Recording additional methods of resetting the disturbance recorder, triggeringthe disturbance recorder from the logic inputs, thresholds on circuitbreaker maintenance counter and contact arcing duty plus 5 fullfault records.

KCGG relays provide overcurrent and earth fault protection for power distributionsystems, industrial power systems and all other applications where overcurrentprotection is required. The relays are used in applications where time gradedovercurrent and earth fault protection is required. The earth fault protectionprovides suitable sensitivity for most systems where the earth fault current is limited.

KCEG relays provide directional overcurrent and earth fault protection.The overcurrent elements can be selectively directionalised, making the relays acost effective option where both directional and non-directional protection isrequired. The sensitivity of earth fault protection has been increased to cover mostapplications. The earth fault protection provides suitable sensitivity for most systemswhere the earth fault current is limited.

KCEU relays provide directional overcurrent and sensitive wattmetric earth faultprotection for systems which are earthed through a Petersen coil.

Integral features in K Range relays include circuit breaker failure protection, backtripping, blocked overcurrent protection for feeders or busbars, cold load pick-upfacilities, load shedding capabilities and two alternative groups of predeterminedsettings. The relays also have integral serial communication facilities via K-Bus.


Section 4. MODELS AVAILABLE

The following list of models is covered by this manual

KCGG 122 One phase overcurrent and earth fault relay

KCGG 142 01 Three phase overcurrent and earth fault relay

KCGG 142 02 Three phase overcurrent and earth fault relay with reduced I/O

KCEG 112 Directional earth fault

KCEG 142 Directional three phase overcurrent and directional earth fault relay

KCEG 152 Three phase overcurrent relay and directional earth fault relay

KCEG 242 Directional three phase overcurrent and directional earth fault relay

KCEU 142 Directional three phase overcurrent and wattmetric sensitive earthfault relay

KCEU 242 Directional three phase overcurrent and wattmetric sensitive earthfault relay

Note: The 100 series of relays are powered by a DC/AC auxiliarysupply. The 200 series of relays are dual powered, ie. poweredby a DC/AC auxiliary supply or from the current transformercircuit in the absence of an auxiliary supply.

K Range series 2 relay Equivalent K Range series 1 relays

KCGG 122 KCGG 110, KCGU 110

KCGG 142 KCGG 120, KCGG 130, KCGG 140, KCGU 140

KCEG 112 KCEG 110, KCEU 110

KCEG 142 KCEG 130, KCEG 140, KCEU 140

KCEG 152 KCEG 150, KCEU 150, KCEG 160, KCEU 160

KCEG 242 KCGG/KCEG 210, KCGG/KCEG 230,KCGG/KCEG 250, KCGG/KCGU 240,KCEG/KCEU 240

KCEU 142 KCEU 141

KCEU 242 KCEU 241

Table of equivalence between K Range series 1 and series 2 relays


Section 5. AVAILABILITY OF MAIN FEATURES

The following table lists the features that vary between models

Feature KCGG KCGG KCGG KCEG KCEG KCEG KCEG KCEU KCEU122 142 01 142 02* 112 142 152 242 142 242

Protection

Overcurrent

Earth fault

Directional overcurrent

Directional earth fault

Underfrequency

Undervoltage

Thermal overload

Wattmetric

Measurement

Frequency

Current

Voltage

Single phase power

Three phase power

Thermal ammeter(s)

Thermal demand(s)

Thermal state

CB operations

CB contact duty

Programmable Inputs/Outputs

Logic inputs 3 8 3 3 8 8 8 8 8

Output relays 4 8 4 4 8 8 8 8 8

* The fully functionality KCGG 142 01 relay is also available as a KCGG 142 02with reduced I/O.




Chapter 2Handling and Installation

SERVICE MANUAL R8551CKCGG 122, 142 Chapter 2KCEG 112, 142, 152, 242 ContentsKCEU 142, 242

1. GENERAL CONSIDERATIONS 11.1 Receipt of relays 11.2 Electrostatic discharge (ESD) 12. HANDLING OF ELECTRONIC EQUIPMENT 13. RELAY MOUNTING 24. UNPACKING 25. STORAGE 3

SERVICE MANUAL R8551CKCGG 122, 142 Chapter 2KCEG 112, 142, 152, 242 Page 1 of 3KCEU 142, 242

Section 1. GENERAL CONSIDERATIONS

1.1 Receipt of relays

Protective relays, although generally of robust construction, require carefultreatment prior to installation on site. Upon receipt, relays should be examinedimmediately to ensure no damage has been sustained in transit. If damage hasbeen sustained during transit a claim should be made to the transport contractorand ALSTOM T&D Protection & Control Ltd should be promptly notified.

Relays that are supplied unmounted and not intended for immediate installationshould be returned to their protective polythene bags.

1.2 Electrostatic discharge (ESD)

The relays use components that are sensitive to electrostatic discharges.The electronic circuits are well protected by the metal case and the internal moduleshould not be withdrawn unnecessarily. When handling the module outside itscase, care should be taken to avoid contact with components and electricalconnections. If removed from the case for storage, the module should be placed inan electrically conducting antistatic bag.

There are no setting adjustments within the module and it is advised that it is notunnecessarily disassembled. Although the printed circuit boards are pluggedtogether, the connectors are a manufacturing aid and not intended for frequentdismantling; in fact considerable effort may be required to separate them. Touchingthe printed circuit board should be avoided, since complementary metal oxidesemiconductors (CMOS) are used, which can be damaged by static electricitydischarged from the body.

Section 2. HANDLING OF ELECTRONIC EQUIPMENT

A person’s normal movements can easily generate electrostatic potentials of severalthousand volts. Discharge of these voltages into semiconductor devices whenhandling electronic circuits can cause serious damage, which often may not beimmediately apparent but the reliability of the circuit will have been reduced.

The electronic circuits are completely safe from electrostatic discharge whenhoused in the case. Do not expose them to risk of damage by withdrawingmodules unnecessarily.

Each module incorporates the highest practicable protection for its semiconductordevices. However, if it becomes necessary to withdraw a module, the folowingprecautions should be taken to preserve the high reliability and long life for whichthe equipment has been designed and manufactured.

1. Before removing a module, ensure that you are at the same electrostaticpotential as the equipment by touching the case.

2. Handle the module by its frontplate, frame or edges of the printed circuit board.Avoid touching the electronic componenets, printed circuit track or connectors.

3. Do not pass the module to another person without first ensuring you are both atthe same electrostatic potential. Shaking hands achieves equipotential.


4. Place the module on an antistatic surface, or on a conducting surface which isat the same potential as yourself.

5. Store or transport the module in a conductive bag.

If you are making measurements on the internal electronic circuitry of anequipment in service, it is preferable that you are earthed to the case with aconductive wrist strap. Wrist straps should have a resistance to ground between500ký – 10Mý.If a wrist strap is not available you should maintain regular contact with the case toprevent a build-up of static. Instrumentation which may be used for makingmeasurements should be earthed to the case whenever possible.

More information on safe working procedures for all electronic equipment can befound in BS5783 and IEC 60147-OF. It is strongly recommended that detailedinvestigations on electronic circuitry or modification work should be carried out ina special handling area such as described in the above-mentioned BS and IECdocuments.

Section 3. RELAY MOUNTING

Relays are dispatched either individually or as part of a panel/rack assembly.If loose relays are to be assembled into a scheme, then construction details can befound in Publication R7012. If an MMLG test block is to be included it should bepositioned at the right-hand side of the assembly (viewed from the front). Modulesshould remain protected by their metal case during assembly into a panel or rack.The design of the relay is such that the fixing holes are accessible without removalof the cover. For individually mounted relays an outline diagram is normallysupplied showing the panel cut-outs and hole centres. These dimensions will alsobe found in Publication R6551.

Section 4. UNPACKING

Care must be taken when unpacking and installing the relays so that none of theparts is damaged or the settings altered. Relays must only be handled by skilledpersons. The installation should be clean, dry and reasonably free from dust andexcessive vibration. The site should be well lit to facilitate inspection. Relays thathave been removed from their cases should not be left in situations where they areexposed to dust or damp. This particularly applies to installations which are beingcarried out at the same time as construction work.


Section 5. STORAGE

If relays are not to be installed immediately upon receipt they should be stored in aplace free from dust and moisture in their original cartons. Where de-humidifierbags have been included in the packing they should be retained. The action of thede-humidifier crystals will be impaired if the bag has been exposed to ambientconditions and may be restored by gently heating the bag for about an hour, priorto replacing it in the carton.

Dust which collects on a carton may, on subsequent unpacking, find its way intothe relay; in damp conditions the carton and packing may become impregnatedwith moisture and the de-humifier will lose its efficiency.

Storage temperature –25°C to +70°C.




Chapter 3Relay Description

SERVICE MANUAL R8551DKCGG 122, 142 Chapter 3KCEG 112, 142, 152, 242 ContentsKCEU 142, 242

1. RELAY DESCRIPTION 12. USER INTERFACE 22.1 Frontplate layout 22.2 LED indications 32.3 Keypad 32.4 Liquid crystal display 32.5 Flag display format 33. MENU SYSTEM 53.1 Default display 53.2 Accessing the menu 53.3 Menu contents 63.4 Menu columns 63.5 System data 73.6 Fault records 83.7 Measurements 1 83.8 Measurements 2 83.9 Measurements 3 93.10 Earth fault 1 93.11 Phase fault 1 103.12 Earth fault 2 113.13 Phase fault 2 123.14 Logic 133.15 Input masks 143.16 Relay masks 143.17 Recorder 154. CHANGING TEXT AND SETTINGS 174.1 Quick guide to menu controls 174.2 To enter setting mode 184.3 To escape from the setting mode 184.4 To accept the new setting 184.5 Password protection 194.6 Entering passwords 194.7 Changing passwords 194.8 Restoration of password protection 204.9 Entering text 204.10 Changing function links 204.11 Changing setting values 204.12 Setting communication address 214.13 Setting input masks 214.14 Setting output masks 214.15 Resetting values and records 214.16 Resetting trip LED indication 22


5. EXTERNAL CONNECTIONS 225.1 Auxiliary supply 235.2 Dual powered relays 235.3 Logic control inputs 235.4 Analogue inputs 245.5 Output relays 255.6 Ouput relay minimum dwell time 255.7 Setting the relay with a PC or laptop 256. ALARM FLAGS 25

Figure 1. Frontplate layout 2Figure 2. Flag display format 4

SERVICE MANUAL R8551DKCGG 122, 142 Chapter 3KCEG 112, 142, 152, 242 Page 1 of 26KCEU 142, 242

Section 1. RELAY DESCRIPTION

The KCGG, KCEG and KCEU relays use numerical techniques to derive protectionand control functions. They can have up to eight multiplexed analogue inputs,sampled eight times per power frequency cycle. The Fourier derived powerfrequency component returns the rms value of the measured quantity. To ensureoptimum performance, frequency tracking is used. The channel that is tracked ischosen on a priority basis, Va, Vb, Vc, Ia, Ib, Ic. Frequency tracking is notemployed on the residual voltage, or current to ensure the maximum harmonicrejection. In the absence of a signal to frequency track, the sampling frequencydefaults to the rated frequency of the power system.

Up to eight output relays can be programmed to respond to any of the protectionor control functions and up to eight logic inputs can be allocated to controlfunctions. The logic inputs are filtered to ensure that induced AC current in theexternal wiring to these inputs does not cause an incorrect response. Software linksfurther enable the user to customise the product for their own particularapplications. They select/interconnect the various protection and control elementsand replace the interconnections that were previously used between the cases ofrelays that provided discrete protection or control functions.

The relays are powered from either a DC or an AC auxiliary supply which istransformed by a wide ranging DC/DC converter within the relay. This providesthe electronic circuits with regulated and galvanically isolated supply rails.The power supply also provides a regulated and isolated field voltage to energisethe logic inputs.

The dual powered version of the relay draws its energising supply from the currenttransformers in the absence of an auxiliary voltage supply. This makes it suitablefor application where the auxiliary supply is not reliable or not available. They canbe used in shunt trip, capacitor discharge and AC series trip arrangements.

An interface on the front of the relay allows the user to navigate through the menuto access data, change settings and reset flags, etc. As an alternative the relayscan be connected to a computer via their serial communication ports and the menuaccessed on-line. This provides a more friendly and intuitive method of setting therelay, as it allows a whole column of data to be displayed at one time instead ofjust a single menu cell. Computer programs are also available that enable settingfiles to be generated off-line and these files can then be downloaded to the relayvia the serial port.

In addition to protection and control functions the relays can display all the valuesthat it measures and many additional ones that it calculates. They also store usefultime stamped data for post fault analysis in fault records, event records anddisturbance records. This data is available via a serial communication port foraccess locally and/or remotely with a computer. The fault records, event recordsand disturbance records can be extracted automatically via the serial port andvalues can be polled periodically to determine trends. Remote control actions canalso be made and to this end many K Range relays have been integrated intoSCADA systems.

K Range relays provide the user with the flexibility to customise the relay for theirparticular applications. They provide many additional features that would beexpensive to produce on an individual basis and, when the low installation costsare taken into account, it will be seen to provide an economic solution forprotection and control.


Section 2. USER INTERFACE

The front plate of the relay provides a man machine interface providing the userwith a means of entering settings to the relay displaying measured values, faultrecords and alarms. The series 2 relays have additional graphics to assist the user.The area in which the fault flags are displayed is divided up to denote the areaassociated with each phase and there is a marked position for the appropriatephase colours to be marked and for labels to be affixed to denote the use of thethree overcurrent stages and the three auxiliary timers.

2.1 Frontplate layout

F + 0

Relay types

Liquidcrystaldisplay

LED indicators

Ratings

Model number

Serial number

Digit identifiers

Entry keys

Hz110/125 V

Vn

KCGG142 KCGG14200102125No P967701

-

In 1 A V110 50/60V

STAGE 2STAGE 1

STAGE 3

ALARMALARM

AUX 2AUX 3

AUX 1

TRIP

*Ð *Ð Ð *

GROUP

CAUX TIMER

EF D

FAULT NoSETTING

3C

AB 89 67 5 4

A B

12 0

HEALTHY

F n _ 2G2 A __ * B __ *B TAU X 2 C * NV <

Flag identifiers

Figure 1: Frontplate layout

The frontplate of the relay carries a liquid crystal display LCD on which data suchas settings and measured values can be viewed. The data is accessed through amenu system. The four keys [F]; [+]; [–] and [0] are used to move around the menu,select the data to be accessed and enter settings. Three light emitting diodes (LEDs)indicate alarm, healthy and trip conditions.

A label at the top corner identifies the relay by both its model number and serialnumber. This information uniquely specifies the product and is required whenmaking any enquiry to the factory about a particular relay. In addition there is arating label in the bottom corner which gives details of the auxiliary voltage,reference voltage (directional relays only) and current ratings. Two handles, one atthe top and one at the bottom of the frontplate, will assist in removing the modulefrom the case.


2.2 LED indications

The three LEDs provide the following functions:

GREEN LED Indicates the relay is powered up and running. In mostcases it follows the watchdog relay but dual poweredrelays are the exception because the watchdog does notoperate for loss of auxiliary supply.Such a condition would be considered a normaloperational condition when the relays are energisedfrom line current transformers alone.

YELLOW LED Indicates alarm conditions that have been detected bythe relay during its self checking routine. The alarm lampflashes when the password is entered (passwordinhibition temporarily overridden).

RED LED Indicates a trip that has been issued by the relay. Thismay be a protection trip or result from a remote tripcommand; this can be determined by viewing the tripflags.

2.3 Keypad

The four keys perform the following functions:

[F] function select/digit select key/next column

[+] put in setting mode/increment value/accept key/previous column

[–] put in setting mode/decrement value/reject key/next column

[0] reset/escape/change default display key

Note: Only the [F] and [0] keys are accessible when the relay cover is in place.

2.4 Liquid crystal display

The liquid crystal display has two lines each of sixteen characters. A back-light isactivated when any key on the frontplate is momentarily pressed and will remain lituntil ten minutes after the last key press. This enables the display to be read in allconditions of ambient lighting.

The numbers printed on the frontplate just below the display, identify the individualdigits that are displayed for some of the settings, ie. function links, relay masks etc.Additional text around the display is used to define the areas in which the variousparts of the fault information will be found.

2.5 Flag display format

Now that there are five full fault records the top four left-hand digits no longerdisplay “Fn”, “Fn-1”, . . . “Fn-4” to denote the last and previous fault flags. Insteadthey now display “Fn” to indicate latched fault flags and “Fnow” to indicateunlatched flags (when cell 0023 is selected from the System Data column).

The next two digits indicate the setting group that was in operation during the faultwhen “Fn” is displayed eg. “G1” indicates setting group 1 and “G2” indicatessetting group 2. When “Fnow” is displayed then the setting group is that which iscurrently active.

The next most important areas are the four marked by a circle. These circles areover printed with a letter (A, B or C) to indicate the phase, or a symbol to represent


an earth fault. Alternatively a coloured disc may be stuck over the circles toindicate the phases by colour eg. red, yellow and blue. There are four characterson the display associated with each of these four areas to flag operation of thestart and operation of the three overcurrent stages for that phase.

STAGE 2STAGE 1

STAGE 3

ALARMALARM

AUX 2AUX 3

AUX 1

TRIP

GROUP

CAUX TIMER

EF D

FAULT NoSETTING

3C

AB 89 67 5 4

A B

12 0

HEALTHY

F n _ 2 G 2 A __ * B __ *B TAU X 2 C * NV <

*Ð*Ð Ð*

Figure 2: Flag display format

Consider the four digits above the circle marked |©|. If the relay trips during afault involving phase C then the first digit will be the letter C to indicate the currentexceeded the I> threshold and that the protection has started. The next threecharacters are flags for each of the three overcurrent stages (t>, t>>, t>>>)associated with that phase (phase C in this example) and an asterisk (*) will bedisplayed for the stage or stages that have operated.

Thus:

C would indicate that a current above the I> setting had been detected bythe phase C element during the fault (START condition).

C* would indicate the first overcurrent stage (t>) had operated

C_* would indicate the second stage (t>>) had timed out

C__* would indicate t>>> had timed out – third overcurrent stage

C*_* would indicate that both t> and t>>> had timed out

Flag information is similarly provided for the other two phases and for earth faults.

The six digits at the left-hand side of the display on the bottom line identify theauxiliary functions AUX1, AUX2, AUX3 as AUX123. Two printed panels below thedisplay may be used to indicate the function of each of the three auxiliary functionsand those of the three main overcurrent functions respectively. The appropriate pre-printed labels can be affixed in these two areas.


The two characters at the extreme right-hand end of the top line of the display willindicate V< when the undervoltage element has operated. Operation of thebreaker failure protection is indicated by the letter ‘B’ and operation of the thermalelement by the letter “T” immediately below the V<. For indication of a local/remote trip via relay RLY7 the ‘B’ is replaced by an ‘R’. Where ‘B’ and ‘R’ are bothvalid, ‘B’ is given priority.

Section 3. MENU SYSTEM

Data within the relays is accessed via a menu table. The table is comprised of cellsarranged in rows and columns, like a spreadsheet. A cell may contain text valueslimits or functions. The first cell in a column, the column heading, contains textidentifying the data grouped under it in that column.

3.1 Default display

The selected default display will normally show on the LCD and a momentary pressof the function key [F] will change the display to the heading for the first column,SYSTEM DATA. Further momentary presses of the [F] key will step down thecolumn, row by row, so that data may be read. If at any time the [F] key is pressedand held for one second the cursor will be moved to the top of the next columnand the heading for that column will be displayed. Further momentary presses ofthe [F] key will then move down the new column, row by row.

A new feature is that pressing the [F] and [0] keys together and holding for onesecond can be used to step back up the menu column. A short press of the [0] keywill switch on the back light for the LCD without changing the display in any way.In this way the full menu may be scanned with just the [F] and [0] keys that areaccessible with the relay cover in place, and reset actions can be effected.

Following a protection trip red trip LED will be lit. The display will changeautomatically from the default display to that of the fault flags for the last fault.Whilst the fault flags are displayed the trip LED can be reset by holding down the[0] for at least one second. The trip LED will be reset and the display will change tothe default display that was last selected. The flag information will not be lost bythis action, it can still be accessed under FAULT RECORDS.

The display will not default to the flag information if the user interface is in use atthe time. The default display will return 15 minutes after the last key press, or it canbe selected more quickly by moving to any column heading and then pressing the[0] key for 1 second. The selected default display will appear unless there hasbeen a fault when the fault flags will be displayed. It is possible to step through theavailable default displays by momentary presses of the reset key [0].

3.2 Accessing the menu

The only settings which can be changed with the cover in place are those that canbe reset either to zero or some preset value. To change any other settings the covermust be removed from the relay to gain access to the [+] and [–] keys that are usedto increment or decrement a value. When a column heading is displayed the [–]key will change the display to the next column and the [+] key will change thedisplay to the previous column, giving a faster selection.

When a cell that can be changed is displayed the action of pressing either the [+]or [–] keys will put the relay in setting mode (indicated by a flashing cursor in thedisplay). To escape from the setting mode without making any change the [0] key


should be depressed for one second. Section 4 gives instructions for changing thevarious types of settings.

Password protection is provided for the configuration settings of the relay becausean accidental change could seriously affect the ability of the relay to perform itsintended functions. Configuration settings include the selection of time curves,function links, CT and VT ratios, opto-input and relay output allocation. Individualprotection settings are protected from change when the relay cover is in place.

3.3 Menu contents

Related data and settings are grouped in separate columns of the menu.Each column has a text heading (in capital letters) that identifies the data containedin that column. Each cell may contain text, values, limits and/or a function.The cells are referenced by the column number/row number. For example 0201 iscolumn 02, row 01. When a cell is displayed the four characters at the top lefthand corner of the LCD indicate the column number and row number in the menutable.

The full menu is given in the following tables, but not all the items listed will beavailable in a particular relay. For example, a single pole earth fault relay wouldnot display any phase fault settings and a non-directional relay would not displayany settings associated with the directional feature. Those cells that do not provideany useful purpose are not made available in the factory configuration.Certain settings will disappear from the menu when the user de-selects them; thealternative setting group is a typical example. If group 2 settings have not beenenabled then the menu columns EARTH FLT 2 and PHASE FLT 2 will be hidden andmake them visible, the system data link SD4 must be set to ‘1’. This note is includedat this time to explain why some of the items listed below may not appear in themenu for a relay that is being compared with the full list.

3.4 Menu columns

The menu tables shown below are for KCEG directional overcurrent and earth faultprotection relays, unless otherwise stated. The directional elements shown in themenu tables are not available in KCGG relays.Column Heading DescriptionNumber

00 SYSTEM DATA Settings and data for the system - relay andserial communications

01 FLT RECORDS Fault records for the last five faults

02 MEASURE 1 Directly measured quantities (V & I etc.)

03 MEASURE 2 Calculated quantities (W & VAR etc.)

04 MEASURE 3 Calculated (additional)

05 EARTH FLT 1 Earth fault protection settings – group 1

06 PHASE FLT 1 Phase fault protection settings – group 1

07 EARTH FLT 2 Earth fault protection settings – group 2

08 PHASE FLT 2 Phase fault protection settings – group 2

09 LOGIC Settings for miscellaneous functions usedin the logic

0A INPUT MASKS User assigned allocation of logic input


0B RELAY MASKS User assigned allocation of output relays

0C RECORDER Settings for the disturbance recorder

The menu cells that are read only are marked [READ].Cells that can be set are marked [SET].Cells that can be reset are marked [RESET].Cells that are password protected are marked [PWP].

3.5 System dataDisplay Status Description0000 SYSTEM DATA READ Column heading0002 Password PWP Password that must be entered before certain settings

may be changed0003 SD Links PWP Function links that enable the user to enable (activate)

the options required0 Rem ChgStg 1 = enable remote setting changes2 Rem CB Ctrl 1 = enable remote control of circuit breaker3 Rem ChgGrp 1 = enable remote change of setting group4 En Grp2 1 = enable group 2 settings to be used and

displayed5 Auto Flag 1 = enable flags to be reset automatically on load

restoration6 Auto Rec 1 = enable disturbance recorder to reset on load

restoration7 Log Evts 8 1 = enable logic inputs and output relay status to be

stored in event records8 Alt Rec Rst 1 = enable alternative reset method for disturbance

recorder0004 Description PWP Product description – user programmable text0005 Plant PWP Plant reference – user programmable text0006 Model READ Model number that defines the product0008 Serial No. READ Serial number – unique number identifying the

particular product0009 Freq SET Default sampling frequency – must be set to power

system frequency (not available on KCEU relays)000A Comms Level READ Indicates the Courier communication level supported

by the product000B Rly Address SET Communication address (1 to 255)000C Plnt Status READ Binary word used to indicate the status of circuit

breakers and isolators000D Ctrl Status READ Binary word used to indicate the status of control data000E Grp now READ Indicates the active setting group000F LS Stage READ Indicates the last received load shedding command0010 CB Control SET Indicates the status of the circuit breaker control0011 Software READ Software reference for the product0020 Log Status READ Indicates the current status of all the logic inputs0021 Rly Status READ Indicates the current status of the output relay drives0022 Alarms READ Indicates the current state of internal alarms0 Uncfg READ Error in factory configuration settings1 Uncalib READ Operating in uncalibrated state2 Setting READ Error detected in stored settings3 No Service READ Protection out-of-service and not functioning


4 No Samples READ No A/D samples but still in service5 No Fourier READ Fourier is not being performed6 Test Wdog SET Test watchdog by setting this bit to “1”0023 FnowG1 READ Indicates the current status of the fault flags

(These flags are not latched)

3.6 Fault recordsDisplay Status Description0100 FLT RECORDS READ Column heading0101 Fault No 1 SET Number of fault record displayed – may be selected

(Fn; Fn -1; Fn -2; . . . Fn -5)0102 Fn G1 READ Flags (latched) indicating the functions that operated

during the fault0103 Ia READ Highest value of current measured in phase A during

the fault0104 Ib READ Highest value of current measured in phase B during

the fault0105 Ic READ Highest value of current measured in phase C during

the fault0106 Io READ Highest value of residual current measured during the

fault0107 Vab READ Value of Vab during the fault0108 Vbc READ Value of Vbc during the fault0109 Vca READ Value of Vca during the fault010A Vo READ Highest value of residual voltage measured during

the fault010B CB Trip Time READ Circuit breaker trip time0110 Clear = O RESET Press [0] key to clear all fault records when this cell is

displayed

3.7 Measurements 1Display Status Description0200 MEASURE 1 READ Column heading0201 Ia READ Measured current in phase A0202 Ib READ Measured current in phase B0203 Ic READ Measured current in phase C0204 Io READ Measured residual current0205 Vab READ Measured line voltage Vab0206 Vbc READ Measured line voltage Vbc0207 Vca READ Measured line voltage Vca0208 Va READ Measured phase voltage Va

(not available on KCEU relays)0209 Vb READ Measured phase voltage Vb

(not available on KCEU relays)020A Vc READ Measured phase voltage Vc

(not available on KCEU relays)020B Vo READ Measured residual voltage Vo020C F READ Measured power system frequency F


3.8 Measurements 2Display Status Description0300 MEASURE 2 READ Column heading0301 3W READ Three phase active power0302 3VA READ Three phase apparent power0303 3VAr READ Three phase reactive power0304 Imax READ Highest of the three phase currents measured – not a

peak demand value0309 Wa READ Active power in phase A

(not available on KCEU relays)030A Wb READ Active power in phase B

(not available on KCEU relays)030B Wc READ Active power in phase C

(not available on KCEU relays)030C PowerFactor READ Power factor – three phase030D VARa READ Reactive power in phase A

(not available on KCEU relays)030E VARb READ Reactive power in phase B

(not available on KCEU relays)030F VARc READ Reactive power in phase C

(not available on KCEU relays)0310 Sum (ops) PWP Number of circuit breaker operations0311 CBdutyA PWP Sum of I, or I2 broken by phase A of circuit breaker0312 CBdutyB PWP Sum of I, or I2 broken by phase B of circuit breaker0313 CBdutyC PWP Sum of I, or I2 broken by phase C of circuit breaker031E Power mode PWP Sets the convention used for signing the direction of

measured power flow

3.9 Measurements 3Display Status Description0400 MEASURE 3 READ Column heading0404 IthA READ Thermal ammeter reading in phase A0405 IthB READ Thermal ammeter reading in phase B0406 IthC READ Thermal ammeter reading in phase C0407 Thermal PWP Thermal state (%)040A Pk IthA PWP Peak thermal ammeter reading in phase A – demand

value040B Pk IthB PWP Peak thermal ammeter reading in phase B – demand

value040C Pk IthC PWP Peak thermal ammeter reading in phase C – demand

value

3.10 Earth fault 1Display Status Description0500 EARTH FLT1 READ Column heading0501 EF Links PWP Software links that are used to select the available

optional earth fault functions1 En Io>> 1 = enable earth fault stage 22 EN Io>>> 1 = enable earth fault stage 33 Drn to> 1 = directionalise earth fault stage 14 Drn to>> 1 = directionalise earth fault stage 25 Drn to>>> 1 = directionalise earth fault stage 3


6 Io>>NoPeak 1 = no peak measurement for stage 2 earth faults (KCGG only)

E Rev Io>>> 1 = reverse direction of third earth fault stage (Io>>>)0502 CT Ratio PWP Overall ratio of the line or neutral CT feeding the

earth fault protection elements0503 VT Ratio PWP Overall ratio of the voltage transformer feeding the

relay0504 Curve PWP Selected characteristic from the definite time or 10

inverse time options0505 Io> SET Current setting for start output and first earth fault

stage0506 to>/TMS SET Time multiplier setting that will be used with a

selected inverse time curve0507 to>/DT SET Time delay that will be effective when the definite time

characteristic is selected0508 toRESET SET Hold time for which the current must remain below

Io> before the timer resets to zero0509 Io>> SET Current setting for second earth fault stage050A to>> SET Time delay for second earth fault stage050B Io>>> SET Current setting for third earth fault stage050C to>>> SET Time delay for third earth fault stage050D Char Angle SET Characteristic angle setting for earth fault directional

element050E Io< SET Setting for earth fault undercurrent element050F Vop> SET Setting for minimum polarising voltage below which

the directional element is blocked0510 Po> SET Wattmetric power threshold

(only available on KCEU relays)

3.11 Phase fault 1Display Status Description0600 PHASE FLT 1 READ Column heading0601 PF Links PWP Software links that are used to select the available

optional phase fault functions0 En Therm 1 = enable thermal element1 En I>> 1 = enable stage 2 overcurrent2 En I>>> 1 = enable stage 3 overcurrent3 Drn t> 1 = directionalise stage 1 overcurrent4 Drn t>> 1 = directionalise stage 2 overcurrent5 Drn t>>> 1 = directionalise stage 3 overcurrent6 I>> NoPeak 1 = No peak measurement for stage 2 overcurrent

(KCGG only)7 I>>> = 2/3 1 = 2 out of 3 phase elements to operate for t>>>

to give an output8 CB blk V< 1 = undervoltage blocked when circuit breaker is

open9 V< any = 1 1 = output for any phase undervoltage;

0 = output for all phases undervoltageA V< P-N = 1 1 = undervoltage responds to phase voltage;

0 = undervoltage responds to line voltage (not available on KCEU relays)

B SynPol = 3.2 1 = synchronous polarising extended to 3.2s;0 = 0.32s

C Brkn Cond 1 = enables broken conductor logic


D En F< 1 = enable under frequency element to initiate tAUX1 (not available on KCEU relays)

E Rev I>>> 1 = reverse direction of third overcurrent stageF All 2/3 1 = 2/3 logic applied to all phase outputs0602 CT Ratio PWP Overall ratio of the line CT feeding the phase fault

protection elements0603 VT Ratio PWP Overall ratio of the voltage transformer feeding the


inverse time options0605 I> SET Current setting for start output and first overcurrent

stage0606 t>/TMS SET Time multiplier setting that will be used with a

selected inverse time curve0607 t>/DT SET Time delay that will be effective when the definite time

characteristic is selected0608 tRESET SET Hold time for which the current must remain below I>

before the timer resets to zero0609 I>> SET Current setting for second overcurrent stage060A t>> SET Time delay for second overcurrent stage060B I>>> SET Current setting for third overcurrent stage060C t>>> SET Time delay for third overcurrent stage060D Char Angle SET Characteristic angle setting for overcurrent directional

element060E I< SET Setting for phase fault undercurrent element060F V< SET Setting for undervoltage element0610 tV< SET Definite time delay for undervoltage feature0611 F< SET Setting for underfrequency

(not available on KCEU relays)0612 th> Alarm SET Thermal alarm level (%)0613 Ith> Trip SET Thermal current rating (trip level = 100%)0614 TC SET Setting for thermal time constant

3.12 Earth fault 2Display Status Description0700 EARTH FLT 2 READ Column heading0701 EF Links PWP Software links that are used to select the available

optional earth fault functions1 En Io>> 1 = enable earth fault stage 22 En Io>>> 1 = enable earth fault stage 33 Drn to> 1 = directionalise earth fault stage 14 Drn to>> 1 = directionalsise earth fault stage 25 Drn to>>> 1 = directionalise earth fault stage 36 Io>> NoPeak 1 = no peak measurement for stage 2 earth faults

(KCGG only)E Rev Io>>> 1 = reverse direction of third earth fault stage (Io>>>)0702 CT Ratio PWP Overall ratio of the line or neutral CT feeding the

earth fault protection elements0703 VT Ratio PWP Overall ratio of the voltage transformer feeding the


inverse time options0705 Io> SET Current setting for start output and first earth fault

stage


0706 to>/TMS SET Time multiplier setting that will be used with aselected inverse time curve

0707 to>/DT SET Time delay that will be effective when the definite timecharacteristic is selected

0708 toRESET SET Hold time for which the current must remain belowIo> before the timer resets to zero

0709 Io>> SET Current setting for second earth fault stage070A to>> SET Time delay for second earth fault stage070B Io>>> SET Current setting for third earth fault stage070C to>>> SET Time delay for third earth fault stage070D Char Angle SET Characteristic angle setting for earth fault directional

element070E Io< SET Setting for earth fault undercurrent element070F Vop> SET Setting for minimum polarising voltage below which

the directional element is blocked0710 Po> SET Wattmetric power threshold

(only available on KCEU relays)

3.13 Phase fault 2Display Status Description0800 PHASE FLT 2 READ Column heading0801 PF Links PWP Software links that are used to select the available

optional phase fault functions0 En Therm 1 = enable thermal element1 En I>> 1 = enable stage 2 overcurrent2 En I>>> 1 = enable stage 3 overcurrent3 Drn t> 1 = directionalise stage 1 overcurrent4 Drn t>> 1 = directionalise stage 2 overcurrent5 Drn t>>> 1 = directionalise stage 3 overcurrent6 I>> NoPeak 1 = No peak measurement for stage 2 overcurrent

(KCGG only)7 I>>> = 2/3 1 = 2 out of 3 phase elements to operate for t>>>

to give an output8 CB blk V< 1 = undervoltage blocked when circuit breaker is

open9 V< any = 1 1 = output for any phase undervoltage;

0 = output for all phases undervoltageA V< P-N = 1 1 = undervoltage responds to phase voltage;

0 = undervoltage responds to line voltageB SynPol = 3.2 1 = synchronous polarising extended to 3.2s;

0 = 0.32sC Brkn Cond 1 = enables broken conductor logicD EN F< 1 = enable under frequency element to initiate tAUX1

(not available on KCEU relays)E Rev I>>> 1 = reverse direction of third overcurrent stageF All 2/3 1 = 2/3 logic applied to all phase outputs0802 CT Ratio PWP Overall ratio of the line CT feeding the phase fault

protection elements0803 VT Ratio PWP Overall ratio of the voltage transformer feeding the


inverse time options0805 I> SET Current setting for start output and first overcurrent

stage


0806 t>/TMS SET Time multiplier setting that will be used with aselected inverse time curve

0807 t>/DT SET Time delay that will be effective when the definite timecharacteristic is selected

0808 tRESET SET Hold time for which the current must remain below I>before the timer resets to zero

0809 I>> SET Current setting for second overcurrent stage080A t>> SET Time delay for second overcurrent stage080B I>>> SET Current setting for third overcurrent stage080C t>>> SET Time delay for third overcurrent stage080D Char Angle SET Characteristic angle seting for overcurrent directional

element080E I< SET Setting for phase fault undercurrent element080F V< SET Setting for undervoltage element0810 tV< SET Definite time delay for undervoltage feature0811 F< SET Setting for underfrequency

(not available on KCEU relays)0812 th>Alarm SET Thermal alarm level (%)0813 Ith>Trip SET Thermal current rating (trip level = 100%)0814 TC SET Setting for thermal time constant

3.14 LogicDisplay Status Description0900 LOGIC READ Column heading0901 LOG Links PWP Software links that are used to select the available

optional logic functions0 CB Rec 1 = enable CB operations and contact duty registers

to be incremented1 CB1*I = 0 1 = CB contact proportional to I;

0 = CB contact duty proportional to I2

2 BF blk strt 1 = enables the start outputs to be reset when breaker failure protection operates

3 tAUX2 = I< 1 = tAUX2 initiated by undercurrent in all three phases

4 tAUX2=/Io< 1 = tAUX2 initiated when the earth fault current exceeds the Io< setting

5 tAUX3 Grp2 1 = tAUX3 selects setting grp26 tAUX2-tAUX3 1 = enables the pick up of tAUX3 to be delayed by

tAUX27 Latch Strt 1 = start latches fault flags and generate fault record8 Hold Grp2 1 = selects and holds the grp2 settings operational9 Rst CBclose 1 = enables a circuit breaker trip to reset the close

pulse timerA Log Rly7 1 = enable relay 7 to initiate fault recordsB tAUX3=DDO 1 = tAUX3 is delayed on drop-off

0 = tAUX3 is delayed on pick-up0902 tBF SET Breaker failure protection time delay setting0903 tAUX1 SET Auxiliary timer 1 setting0904 tAUX2 SET Auxiliary timer 2 setting0905 tAUX3 SET Auxiliary timer 3 setting0906 tTRIP SET Trip pulse time setting0907 tCLOSE SET Close pulse time setting0908 CB ops> SET Alarm 1 setting for excessive circuit breaker operations


0909 CB duty> SET Alarm 1 setting for excessive circuit breaker contactduty

090F Display SET Default display that is selected on power-up0 Manufact Manufacturer’s name1 Descript Description of product2 Plant Plant reference3 Thermal Thermal State (%)4 IthA B C Thermal ammeter readings for each of the three

phases5 Ia Ib Ic Instantaneous reading of phase currents (prospective

value of thermal ammeter)6 Ia Io Vab Vo Line current and voltage plus residual current and

voltage7 kW kVAr Active and reactive three phase power

3.15 Input masksDisplay Status Description0A00 INPUT MASKS READ Column heading0A01 Blk to> PWP Logic input to block first stage earth fault timer to>0A02 Blk to>> PWP Logic input to block second stage earth fault timer

to>>0A03 Blk to>>> PWP Logic input to block third stage earth fault timer

to>>>0A04 Blk t> PWP Logic input to block first stage overcurrent timer t>0A05 Blk t>> PWP Logic input to block second stage overcurrent timer

t>>0A06 Blk t>>> PWP Logic input to block third stage overcurrent timer

t>>>0A07 L Trip PWP Logic input to initiate trip pulse timer from external

input0A08 L Close PWP Logic input to initiate close pulse timer from external

input0A09 Ext Trip PWP Logic input to initiate breaker fail and records from

an external trip signal0A0A Aux 1 PWP Logic input to initiate timer tAUX1 from external input0A0B Aux 2 PWP Logic input to initiate timer tAUX2 from external input0A0C Aux 3 PWP Logic input to initiate timer tAUX3 from external input0A0D Set Grp 2 PWP Logic input to select group 2 protection settings from

external input0A0E CB Closed PWP Logic input to indicate circuit breaker in closed

position0A0F CB Open PWP Logic input to indicate circuit breaker in open position0A10 Bus2 PWP Logic input to indicate circuit breaker in bus 2

position0A11 Reset Ith PWP Logic input to block/reset thermal protection,

also resets thermal ammeters

3.16 Relay masksDisplay Status Description0B00 RELAY MASKS READ Column heading0B01 Io> Fwd PWP Earth fault forward start (non directional start for non

directional relays)0B02 Io> Rev PWP Earth fault reverse start (only available when

directionalised)


0B03 to> PWP First stage time delayed earth fault output0B04 to>> PWP Second stage time delayed earth fault output0B05 to>>> PWP Third stage time delayed earth fault output0B06 I> Fwd PWP Overcurrent forward start (non directional start for non

directional relays)0B07 I> Rev PWP Overcurrent reverse start (only available when

directionalised)0B08 tA> PWP First stage time delayed overcurrent output for

phase A0B09 tB> PWP First stage time delayed overcurrent output for

phase B0B0A tC> PWP First stage time delayed overcurrent output for

phase C0B0B t>> PWP Second stage time delayed overcurrent output0B0C t>>> PWP Third stage time delayed overcurrent output0B0D CB Trip PWP Trip pulse output0B0E CB Close PWP Close pulse output0B0F CB Fail PWP Breaker fail output for initiation of back tripping0B10 Aux 1 PWP Output from the auxiliary 1 time delayed function0B11 Aux2 PWP Output from the auxiliary 2 time delayed function0B12 Aux3 PWP Output from the auxiliary 3 time delayed function0B13 tV< PWP Undervoltage time delayed output0B14 Level 1 PWP Output in response to command to load shed to

level 1 (not available on KCEU relays)0B15 Level 2 PWP Output in response to command to load shed to

level 2 (not available on KCEU relays)0B16 Level 3 PWP Output in response to command to load shed to

level 3 (not available on KCEU relays)0B17 thAlarm PWP Thermal overload alarm0B18 thTrip PWP Thermal overload trip0B19 CB Alarm PWP Alarm for circuit breaker maintenance

3.17 RecorderDisplay Status Description0C00 RECORDER READ Column heading0C01 Control SET Manual stop/start control (running = started;

triggered = stopped)0C02 Capture SET Select the functions to be captured: magnitudes/

phase angles/samples0C03 Post trigger SET Select the number of samples recorded after the

trigger (1 to 511)0C04 Logic trig SET Select the logic input to trigger the recorder

(0 to 7 pick-up or drop-off)0 +Opto0 Trigger in response to energisation of logic input L01 +Opto1 Trigger in response to energisation of logic input L12 +Opto2 Trigger in response to energisation of logic input L23 +Opto3 Trigger in response to energisation of logic input L34 +Opto4 Trigger in response to energisation of logic input L45 +Opto5 Trigger in response to energisation of logic input L56 +Opto6 Trigger in response to energisation of logic input L67 +Opto7 Trigger in response to energisation of logic input L78 –Opto0 Trigger in response to de-energisation of logic

input L0


9 –Opto1 Trigger in response to de-energisation of logicinput L1

A –Opto2 Trigger in response to de-energisation of logicinput L2

B –Opto3 Trigger in response to de-energisation of logicinput L3

C –Opto4 Trigger in response to de-energisation of logicinput L4

D –Opto5 Trigger in response to de-energisation of logicinput L5

E –Opto6 Trigger in response to de-energisation of logicinput L6

F –Opto7 Trigger in response to de-energisation of logicinput L7

0C05 Relay Trig SET Select the output relay tio trigger the recorder(0 to 7 pick-up or drop-off)

0 +Rly 0 Trigger in response to energisation of output relayRLY 0








8 –Rly 0 Trigger in response to de-energisation of output relayRLY 0

9 –Rly 1 Trigger in response to de-energisation of output relayRLY 1

A –Rly 2 Trigger in response to de-energisation of output relayRLY 2

B –Rly 3 Trigger in response to de-energisation of output relayRLY 3

C –Rly 4 Trigger in response to de-energisation of output relayRLY 4

D –Rly 5 Trigger in response to de-energisation of output relayRLY 5

E –Rly 6 Trigger in response to de-energisation of output relayRLY 6

F –Rly 7 Trigger in response to de-energisation of output relayRLY 7


Section 4. CHANGING TEXT AND SETTINGS

Settings and text in certain cells of the menu can be changed via the userinterface. To do this the cover must be removed from the front of the relay so thatthe [+] and [–] keys can be accessed.

4.1 Quick guide to menu controls

Quick guide to menu control with the four keys

Current display Key press Effect of action

Default display [0] long Back-light turns ON – no other effect

[0] short Steps through the available default displays

[F] steps down to column heading SYSTEMDATA

[+] Back-light turns ON – no other effect

[–] Back-light turns ON – no other effect

Fault flags after a trip [0] short Back-light turns ON – no other effect

[F] steps down to column heading SYSTEMDATA without resetting the fault flags

[0] long resets trip LED and returns default display

[+] Back-light turns ON – no other effect

[–] Back-light turns ON – no other effect

Column heading [0] short Back-light turns ON – no other effect

[0] long Re-establishes password protectionimmediately and returns the default display

[F] long move to next column heading

[F] short steps down the menu to the next item inthe column

[–] move to next column heading

[+] move to previous column heading

Any menu cell [F] short steps down the menu to the next item inthe column

[F] long displays the heading for the next column

[F] + [0] steps back up the menu to the previousitem

[0] short Back-light turns ON – no other effect

[0] long Resets the value if the cell is resettable

Any settable cell [+] or [–] Puts the relay in setting mode. The passwordmust first be entered for protected cells


Current display Key press Effect of action

Setting mode [0] Escapes from the setting mode without asetting change

[+] Increments value – with increasing rapidity ifheld

[–] Decrements value – with increasing rapidityif held

[F] Changes to the confirmation display

[F] If function links, relay or input masks aredisplayed the [F] key will step through themfrom left to right and finally changing to theconfirmation display

Confirmation mode [+] Confirms setting and enters new setting ortext

[–] Returns prospective change to check/modify

[0] Escapes from the setting mode without asetting change

The actions shown in the shaded area can only be performed when the cover isremoved.

[F] long means press F key and hold for longer than 1s

[F] short means press F key and hold for less than 1s

[F] means press the F key length of time does not change the response

4.2 To enter setting mode

Give the [F] key a momentary press to change from the selected default displayand switch on the back-light; the heading SYSTEM DATA will be displayed.Use the [+] and [–] keys, or a long press of the [F] key, to select the columncontaining the setting, or text that is to be changed. Then with the [F] key stepdown the column until the contents of that cell are displayed. Press the [+] key toput the relay into the setting mode. Setting mode will be indicated by a flashingcursor on the bottom line of the display. If the cell is read-only, or passwordprotected, then the cursor will not appear and the relay will not be in the settingmode.

4.3 To escape from the setting mode

IMPORTANT! If at any time you wish to escape from the setting mode withoutmaking a change to the contents of the selected cell: Hold the [0] key depressedfor 1s, the original setting will be returned and the relay will exit the setting mode.

4.4 To accept the new setting

Press the [F] key until the confirmation display appears:

Are you sure?

+ = YES – = NO

Press the [0] key if you decide not to make any change.

Press the [–] key if you want to further modify the data before entry.

Press the [+] key to accept the change. This will terminate the setting mode.


4.5 Password protection

Password protection is provided for the configuration settings of the relay.This includes time curve selection, CT and VT ratios, function links, input masks andrelay masks. Any accidental change to configuration could seriously affect theability of the relay to perform its intended functions, whereas, a setting error mayonly cause a grading problem. Individual settings are protected from change whenthe relay cover is in place by preventing direct access to the [+] and [–] keys.

The password consists of four characters that may contain any upper case letterfrom the alphabet. The password is initially set in the factory to AAAA, but it canbe changed by the user to another combination if necessary. If the password is lostor forgotten, access to the relay will be denied. However, if the manufacturer ortheir agent is supplied with the serial number of the relay, a back-up password canbe supplied that is unique to that particular product.

4.6 Entering passwords

Using the [F] key, select the password cell [0002] in the SYSTEM DATA column ofthe menu. The word “Password” is displayed and four stars. Press the [+] key andthe cursor will appear under the left hand star. Now use the [+] key to step throughthe alphabet until the required letter is displayed. The display will increment fasterif the key is held down and the [–] key can be used in a similar way to movebackwards through the alphabet. When the desired character has been set the [F]key can be given a momentary press to move the cursor to the position for the nextcharacter. The process is then repeated to enter the remaining characters thatmake up the password. When the fourth character is acknowledged by amomentary press of the [F] key the display will read:

Are you sure?

+ = YES – = NO

Press the [0] key if you decide not to enter the password.

Press the [–] key if you want to modify the entry.

Press the [+] to enter the password. The display will then show four stars and if thepassword was accepted the alarm LED will flash. If the alarm LED is not flashingthe password was not accepted – a further attempt can be made to enter it, or the[F] key pressed to move to the next cell.

Note: When the password cell is displayed, do not press the [+] or [–] key whilstthe alarm LED is flashing unless you want to change the password!

4.7 Changing passwords

When the password has been entered and the alarm LED is flashing the [+] key ispressed to put the relay in setting mode. A new password can now be entered asdescribed in Section 4.6. After entering the fourth character make a note of thenew password shown on the display before pressing the [F] key to obtain theconfirmation display.

Are you sure?

+ = YES – = NO

Press the [0] key if you decide not to enter the new password.

Press the [–] key if you want to modify your entry.

Press the [+] to enter the new password which will then replace the old one.


Note: Make sure the new password has been written down before it is enteredand that the password being entered agrees with the written copy beforeaccepting it. If the new password is not entered correctly you may bedenied access in the future. If the password is lost a back-up passwordunique to that relay can be provided from the factory, or certain agents, ifthe serial number of the product is quoted.

4.8 Restoration of password protection

Password protection is reinstated when the alarm LED stops flashing. This will occurfifteen minutes after the last key press. To restore the password protection withoutwaiting for the fifteen minute time-out, select the password cell or any columnheading and hold the reset key [0] depressed for 1s. The alarm LED will cease toflash to indicate the password protection is restored.

4.9 Entering text

Enter the setting mode as described in Section 4.2 and move the cursor with the [F]key to where the text is to be entered or changed. Then using the [+] and [–] keys,select the character to be displayed. The [F] key may then be used to move thecursor to the position of the next character and so on. Follow the instructions inSection 4.4 to exit from the setting change.

4.10 Changing function links

Select the column heading required and step down to the function links “SD Links”,“EF Links”, “PF Links”, or “LOG Links” and press either the [+] or [–] to put therelay in a setting change mode. A cursor will flash on the bottom line at theextreme left position. This is link “F”; as indicated by the character printed on thefrontplate under the display.

Press the [F] key to step along the row of links, one link at a time, until some textappears on the top line that describes the function of a link. The [+] key willchange the link to a “1” to select the function and the [–] key will change it to a“0” to deselect it. Follow the instructions in Section 4.4 to accept the settingchange.

Not all links can be set, some being factory selected and locked. The links that arelocked in this way are usually those for functions that are not supported by aparticular relay, when they will be set to “0”. Merely moving the cursor past a linkposition does not change it in any way.

4.11 Changing setting values

Move through the menu until the cell that is to be edited is displayed. Press the [+]or [–] key to put the relay into the setting change mode. A cursor will flash in theextreme left hand position on the bottom line of the display to indicate that therelay is ready to have the setting changed. The value will be incremented in singlesteps by each momentary press of the [+] key, or if the [+] key is held down thevalue will be incremented with increasing rapidity until the key is released.Similarly the [–] key can be used to decrement the value. Follow the instructions inSection 4.4 to exit from the setting change.

Note: When entering CT RATIO or VT RATIO the overall ratio should be entered,ie. 2000/5A CT has an overall ratio of 400:1. With rated current appliedthe relay will display 5A when CT RATIO has the default value of 1:1 andwhen the ratio is set to 400:1 the displayed value will be 400 x 5 =2000A.


4.12 Setting communication address

The communication address will be set to 255, the global address to all relays onthe network, when the relay is first supplied. Reply messages are not issued fromany relay for a global command, because they would all respond at the same timeand result in contention on the bus. Setting the address to 255 will ensure thatwhen first connected to the network they will not interfere with communications onexisting installations. The communication address can be manually set by selectingthe appropriate cell for the SYSTEM DATA column, entering the setting mode asdescribed in Section 4.2 and then decrementing or incrementing the address.Then exit setting mode as described in Section 4.4.

To automatically allocate an address to the relay, see Chapter 6.

4.13 Setting input masks

An eight bit mask is allocated to each protection and control function that can beinfluenced by an external input applied to one or more of the logic inputs.When the menu cell for an input mask is selected the top line of the display showstext describing the function to be controlled by the inputs selected in the mask.A series of “1”s and “0”s on the bottom line of the display indicates which logicinputs are selected to exert control. The numbers printed on the frontplate under thedisplay indicate each of the logic inputs (L7 to L0) being displayed.A “1” indicates that a particular input is assigned to the displayed control functionand a “0” indicates that it is not. The same input may be used to control more thanone function.

4.14 Setting output masks

An eight bit mask is allocated to each protection and control function. When amask is selected the text on the top line of the display indicates the associatedfunction and the bottom line of the display shows a series of “1”s and “0”s for theselected mask. The numbers printed on the frontplate under the display indicate theoutput relay (RLY7 to RLY0) to which each bit is associated. A “1” indicates that therelay will respond to the displayed function and a “0” indicates that it will not.

A logical “OR” function is performed on the relay masks so that more than onerelay may be allocated to more than one function. An output mask may be set tooperate the same relay as another mask so that, for example, one output relaymay be arranged to operate for all the functions required to trip the circuit breakerand another for only those functions that are to initiate autoreclose.

4.15 Resetting values and records

Some values and records can be reset to zero, or some predefined value.To achieve this the menu cell must be displayed and then the [0] key helddepressed for at least one second to effect the reset. The fault records are slightlydifferent because they are a group of settings and to reset these the last cell underFLT RECORDS must be selected. This will display:

Clear = [0]

To reset ALL FIVE fault records hold the [0] key depressed for more than 1s. If therecords are not cleared the oldest record will be overwritten by the next fault.


4.16 Resetting trip LED indication

The trip LED can be reset when the flags for the last fault are displayed. They aredisplayed automatically after a trip occurs, or can be selected in the fault recordcolumn. The reset is effected by depressing the [0] key for 1s. Resetting the faultrecords as described in 4.15 will also reset the trip LED indication.

Set function link SD5 to “1” for the trip LED to automatically reset. This will thenoccur when the circuit breaker is reclosed and the load current exceeds theundercurrent setting (I<) for three seconds. The LED will not reset if the circuitbreaker is not reclosed and so it is a useful function to employ with autorecloseequipment, as it will prevent unwanted trip flags being displayed after a successfulreclosure of the circuit breaker.

Section 5. EXTERNAL CONNECTIONS

Standard connection tableFunction Terminal FunctionEarth terminal – 1 2 – Not usedWatchdog relay b 3 4 m Watchdog relay(break contact) – 5 6 – (make contact)48V field voltage [+] 7 8 [–] 48V field voltageCapacitor trip voltage [+] 9 10 [–] Capacitor trip voltageNot used – 15 16 – Not usedAuxiliary voltage input (+) 13 14 (–) Auxiliary voltage inputNot used – 15 16 – Not usedA phase voltage IN 17 18 IN B phase voltageC phase voltage IN 19 20 OUT Common voltage neutralA phase current IN 21 22 OUT A phase currentB phase current IN 23 24 OUT B phase currentC phase current IN 25 26 OUT C phase currentNeutral current IN 27 28 OUT Neutral currentOutput relay 4 – 29 30 – Output relay 0

31 32Output relay 5 – 33 34 – Output relay 1



43 44Opto control input L3 (+) 45 46 (+) Opto control input L0Opto control input L4 (+) 47 48 (+) Opto control input L1Opto control input L5 (+) 49 50 (+) Opto control input L2Opto control input L6 (+) 51 52 (–) Common L0/L1/L2Opto control input L7 (+) 53 54 – K-BUS serial portCommon L3/L4/L5/L6/L7 (–) 55 56 – K-BUS serial port

Key to connection tables

[+] and [–] indicate the polarity of the dc output from these terminals

(+) and (–) indicate the polarity for the applied dc supply

IN/OUT the signal direction for forward operation


Note: All relays have standard Midos terminal blocks to which connections canbe made with either 4mm screws or 4.8mm pre-insulated snap-onconnectors. Two connections can be made to each terminal.

5.1 Auxiliary supply

The auxiliary voltage may be DC or AC provided it is within the limiting voltagesfor the particular relay. The voltage range will be found on the frontplate of therelay; it is marked Vx = (24V – 125V) or (48V – 250V). An ideal supply to use fortesting the relays will be 50V DC or 110V AC because these values fall withinboth of the auxiliary voltage ranges.

The supply should be connected to terminals 13 and 14 only. To avoid anyconfusion it is recommended that the polarity of any applied voltage is kept to theMidos standard:– for dc supplies the positive lead connected to terminal 13 and the negative to

terminal 14– for ac supplies the live lead is connected to terminal 13 and the neutral lead to

terminal 14.

5.2 Dual powered relays

Dual powered relays derive power from the current transformer circuit and may beused with this power source alone. However, the application of an auxiliary DC orAC voltage will enable lower earth fault settings to be used, also settings to beapplied and data to be read when the load current is insufficient to power therelay. It will also allow communications to be maintained at such times.

When powered from the CT circuit alone the 48V field voltage will be available topower the opto-isolated control inputs when the protection starts up. The phasefault current setting range is limited to the minimum current levels at which thepower requirements of the relay can be maintained. See Technical Data,Chapter 7. This model of relay is rated for an auxiliary voltageVx = (100V to 250V).

Note: The capacitance discharge circuit is not isolated from the auxiliary supplyand to prevent the relay from being damaged, no external groundconnection should be made to this circuit.

5.3 Logic control inputs

There are a number of logic control inputs to the relay that are optically coupled toprovide galvanic isolation between the external and internal circuits. They arerated at 48V and the power supply within the relay provides an isolated fieldvoltage to energise them. This arrangement keeps the power consumption of theseinputs to a minimum and ensures that they always have a supply to energise themwhen the relay is operational. This is particularly important for the dual poweredrelay when there is no auxiliary supply voltage available and the relay isenergised by the current from the line current transformers.

Software filtering is applied to prevent induced AC signals in the external wiringcausing operation of logic inputs. This is achieved by sampling the logic inputseight times per cycle and five consecutive samples have to indicate that the input isenergised in a positive sense before it is accepted. This ensures that the inputs arerelatively immune to spurious operation from induced AC signals in the wiring.The capture time is:

12 ±2.5ms at 50Hz10.4 ±2.1ms at 60Hz (not available on KCEU relays)


Note: These inputs will not capture a fleeting contact unless it dwells in the closedstate for a time exceeding the above values.

The opto-isolated logic control inputs are divided into two groups. Three (L0, L1,L2) have their common connection on terminal 52 and are fitted to the KCGG 14202 relay and relays with no more than two analogue inputs. The remainder (L3,L4, L5, L6, L7) have their common connection on terminal 55 and are fitted torelays with 8 opto inputs. When they are to be energised from the field voltagethen terminals 52 and 55 must be connected to terminal 8, the negative of the fieldvoltage. The logic inputs can then be energised by connecting a volt free contactbetween the positive of the field voltage, terminal 7, and the terminal for theappropriate logic input.

The circuit for each opto-isolated input contains a blocking diode to protect it fromany damage that may result from the application of voltage with incorrect polarity.Where the opto-isolated input of more than one relay is to be controlled by thesame contact it will be necessary to connect terminal 7 of each relay together toform a common line. In the example circuit below, contact X operates L1 of relay 1and contact Y operates L0 of relay 1 as well as L0 and L1 of relay 2. There are noconnections made to L2 as it is not used on either relay.

The logic inputs can be separated into two isolated groups when it is necessary toenergise some from the station battery. The logic inputs are rated at 48V and it willbe necessary to connect an external resistor in series with the input if the battery isof higher rated voltage. The value of this resistor should be 2.4ký for everyadditional 10V.

The field voltage is not earthed and has insulation rated for 2kV for 1 minute.Thus if necessary the positive terminal of the field voltage could be connected tothe positive terminal on the external battery. Also the two separate groups of logicinputs could be energised from separate batteries.

5.4 Analogue inputs

The relays can have up to eight analogue inputs, two on the microprocessor boardand six on the auxiliary expansion board. Each is fed via an input transducer, alow pass filter and a three range scaling amplifier. The analogue signals aresampled eight times per cycle on each channel as the sampling rate tracks thefrequency of the input signal.

The wide setting range provided on the auxiliary powered version of the relays issufficient to enable the 5A version of the relay to operate from either 1A or 5Acurrent transformers and this version of the relay can be used where dual ratedrelays are specified. Alternatively, the wide setting range makes the relay suitablefor use on circuit breakers that may be applied to a wide range of load circuitratings with only one current transformer ratio. For example a circuit breaker ratedat 2kA and fitted with current transformers rated at 2000/10A (or 2000/2A) andrelays rated at 5A (or 1A) could be applied to circuits with load ratings from 100Ato 2000A.

The dual powered relays have a narrower setting range and must be used withcurrent transformers that match their current rating. Thermal dissipation is thelimitation for the upper end of the setting range and the energy required to powerthe relay is the limitation at the lower end. When the relay is powered from anadditional auxiliary voltage source, earth fault settings can be applied below thatat which the relay can derive sufficient power from the CTs. For this reason theearth fault setting range has not been restricted.


5.5 Output relays

Four programmable output relays are provided on the KCGG 142 02 relay andrelays with no more than two analogue inputs and eight on all other models. Theycan be arranged to operate in response to any or all of the available functions bysuitably setting the output masks. The protection and control functions to whichthese relays respond are selectable via the menu system of the relay.

In addition there is a watchdog relay which has one make and one break contact.Thus it can indicate both healthy and failed conditions. As these contacts aremainly used for alarm purposes they have a lower rating than the programmableoutputs. The terminal numbers for the output relay contacts are given in the table atthe start of Section 5.

5.6 Ouput relay minimum dwell time

Outputs from t>, t>>, t>>>, to>, to>>, to>>> have a minimum dwell of 100ms.The thermal trip will have an inherent delay dependent on the selected timeconstant. The contact dwell ensures a positive trip signal is given to the circuitbreaker.

All other outputs such as I>, I>>, I>>>, Io>, Io>>, Io>>>, tV>, Aux1, Aux2 andAux3 have no deliberate dwell time added to them. This is because they are eitherfollowed by a timer, or used for control purposes which require a faster reset time.

5.7 Setting the relay with a PC or laptop

Connection to a personal computer (PC) or lap top via a K-Bus/RS232 interfacetype KITZ 101 will enable settings to be changed more easily. Software isavailable for the PC that allows on line setting changes in a more user friendly waywith a whole column of data being displayed instead of just single cells. Settingfiles can also be saved to floppy disk and downloaded to other relays of the sametype. There are also programs available to enable setting files to be generated off-line, ie. away from the relays that can be later down-loaded as necessary.

The communication connections and available software are covered under‘Applications’ in Chapter 6.

Section 6. ALARM FLAGS

A full list of the alarm flags will be found in Section 3.3 and is located in cell 0022of the SYSTEM DATA column of the menu. They consist of nine characters that maybe either “1” or “0” to indicate the set and reset states respectively. The controlkeys perform for this menu cell in the same way as they do for function links.The cell is selected with the function key [F] and the relay then put in the settingmode by pressing the [+] key to display the cursor. The cursor will then be steppedthrough the alarm word from left to right with each press of the [F] key and textidentifying the alarm bit selected will be displayed.

The only alarm flag that can be manually set is the bit 6, the watchdog test flag.When this flag is set to “1” the watchdog relay will change state and the greenLED will extinguish.

When any alarm flag is set the alarm LED will be continuously lit. However, there isanother form of alarm condition that will cause the alarm LED to flash and thisindicates that the password has been entered to allow access to change protected


settings within the relay. This is not generally available as a remote alarm and itdoes not generate an alarm flag.

Note: No control will be possible via the key pad if the “unconfigured” alarm israised because the relay will be locked in a non-operate state.

Types KCGG 122, 142KCEG 112, 142, 152, 242 and


Relays

Service Manual

Chapter 4Application of Protection Functions


1. CONFIGURATION 11.1 Configuring the relay 11.2 Default configuration 22. CHANGING THE CONFIGURATION OF THE RELAY 22.1 System data (SD) 22.2 Earth fault links (EF) 32.3 Phase fault links (PF) 42.4 Logic links (LOG) 52.5 Preferred use of logic inputs 62.6 Preferred use of output relays 63. OVERCURRENT AND EARTH FAULT PROTECTION 74. FIRST STAGE OVERCURRENT AND EARTH FAULT LOGIC 84.1 Start function 84.2 Definite time 94.3 Inverse time curves 94.4 Reset timer 104.5 Matching the reset time response of an electromechanical relay 104.6 Protection against intermittent recurrent faults 104.7 Time graded protection 114.8 Dual rate inverse time curves 125. SECOND/THIRD STAGE OVERCURRENT AND EARTH FAULT LOGIC 125.1 Two out of three logic 135.2 Broken conductor logic 135.3 Transformer inrush currents 135.4 Sensitivity to harmonics 145.5 Autoreclose inhibition of instantaneous low set 145.6 Blocked overcurrent protection 145.6.1 Blocked IDMT overcurrent 145.6.2 Blocked short time overcurrent 155.7 Protection of busbars on radial system 165.8 Points to consider with blocking schemes 175.9 Back-up transfer tripping scheme 185.10 Restricted earth fault protection 185.10.1 Setting voltage for stability: 185.10.2 Rs, stabilising resistor 195.10.3 Is, current setting 195.10.4 Metrosil assessment 195.11 Rectifier protection 205.12 Cold load pick-up 216. DIRECTIONAL OVERCURRENT 236.1 Directional overcurrent logic 236.2 Directional start output 236.3 Directional first stage overcurrent 246.4 Directional second and third overcurrent stages 246.5 Directional earth fault logic 246.6 Application of directional phase fault relays 246.7 Synchronous polarisation 266.8 Application of directional earth fault relays 266.9 Power directional earth fault element 27


6.10 Directional stability for instantaneous elements 286.11 Protection of circuits with multiple in-feeds 286.11.1 Blocked directional overcurrent protection 296.11.2 Blocked overcurrent protection for the feeder 296.11.3 Blocked overcurrent protection for the bus section 297. THERMAL OVERCURRENT 307.1 Thermal state 317.2 Thermal trip and alarm levels 317.3 Operation time 317.4 Thermal memory 317.5 Thermal reset 327.6 Dual time constant characteristics 327.7 Application of thermal protection 338. UNDERCURRENT 348.1 Breaker failure protection 349. UNDERVOLTAGE 359.1 Undervoltage trip 359.2 Voltage controlled overcurrent protection 3610. UNDER FREQUENCY 3611. AUXILIARY TIMERS 3611.1 Extra earth fault stage 3711.2 Loss of load protection 3711.3 Delayed under frequency trip 3712. SETTING GROUP SELECTION 3812.1 Remote change of setting group 3812.2 Manual change of setting group 3812.3 Controlled change of setting group 3813. DUAL POWERED RELAYS 3913.1 Powered from current transformers alone 3913.2 Powered from an auxiliary AC voltage and from current transformers 4013.3 Special application notes for dual powered relays 4013.4 Dead substation protection 4113.5 Capacitor discharge tripping 4113.6 AC series tripping 4114. AUTORECLOSE - SINGLE SHOT SCHEME 4214.1 Overview 4214.2 Connections 4314.3 Successful reclose description 4414.4 Unsuccessful reclose 4514.5 Blocking instantaneous low set protection when reclosing 4514.6 Circuit breaker operation counter 46


Figure 1: Available overcurrent characteristics and their settings 7Figure 2: First stage overcurrent and earth fault logic. 8Figure 3: Matching electromechanical reset time 10Figure 4: Intermittent recurrent fault 11Figure 5: Dual rate curves 12Figure 6: Second and third stage overcurrent logic 13Figure 7: Blocked IDMT overcurrent 15Figure 8: Blocked overcurrent for busbar protection 16Figure 9: Back-up transfer trip scheme 17Figure 10: Protection for silicon rectifiers 20Figure 11: Matching curve to load and thermal limit of rectifier 20Figure 12: Compensation for motor starting current 22Figure 13: Directional characteristic 23Figure 14: Directional overcurrent relay logic 25Figure 15: Circuit with multiple infeeds 29Figure 16: Thermal alarm and trip logic 30Figure 17: Circuit breaker fail logic 34Figure 18: Undervoltage logic 35Figure 19: Auxiliary timer logic 37Figure 20: Setting group selection logic 38Figure 21: Start-up time delay 39Figure 22: Capacitor discharge trip 41Figure 23: AC series trip arrangement 42Figure 24: Connection diagram for single shot autoreclose scheme 43Figure 25: Successful autoreclose sequence 44Figure 26: Unsuccessful autoreclose sequence 45


Section 1. CONFIGURATION

The settings that customise the relay for a particular application are referred to asthe configuration. They include the function links, input masks, relay masks, etc.and they are password protected to prevent them being changed accidentally.Together these settings select the functions that are to be made available and howthey are to be interconnected.

Before the advent of integrated numerical relays, protection and control schemescomprised individual relays that had to be interconnected and a diagram wasproduced to show these interconnections. The configuration of a numerical relay isthe software equivalent of these interconnections. With the software approach,installations can be completed in much shorter times, especially for repeatschemes, saving valuable time and cost. A second advantage is the ability to makesome changes without having to disturb the external wiring.

Before the connection diagrams can be drawn for an installation, it will benecessary to decide how the logic within the relay is to function. A copy of thelogic diagram will be found at the back of this manual. It should be copied and theappropriate squares in the input and relays masks should be shaded in to showwhich logic inputs and output relays are to be assigned in each mask. The functionlinks should then be drawn on the diagram in position “0” or “1” as required.

These software links may turn functions on, or off, and when in the “off” state someunnecessary settings may not appear in the menu. The second and thirdovercurrent stages are typical examples of this. As supplied the third overcurrentstage is turned off and its associated settings I>>>/t>>> will not appear in themenu. The function link settings can now be read off the logic diagram andentered as a series of ones and noughts, in the boxes provided on the logicdiagram.

Case connection diagrams will be found at the back of this manual for the currentmodels of K Range directional and non directional overcurrent relays. They may becopied and notes added in the appropriate boxes to indicate the function of thelogic inputs and relay outputs. This diagram will then give the appropriate terminalnumbers to which the external wires must be connected. In particular, it will showthe terminal numbers to which the current and voltage transformers connections areto be made.

Enough information is available from the logic and case connection diagrams toenable the full external wiring diagrams to be drawn and the operation ofcomplete protection and control scheme to be understood.

1.1 Configuring the relay

Each scheme of protection and control will have its own particular configurationsettings. These can be named appropriately and the name entered as the“description” in cell 0004 in the system data column of the menu. If the scheme islikely to become a standard that is to be applied to several installations it would beworthwhile storing the configuration on a floppy disc so that it can be downloadedto other relays.

The configuration file can be made even more useful by adding appropriategeneral settings for the protection and control functions. It will then only require theminimum of settings to be changed during commissioning the installation.


1.2 Default configuration

The relays are provided with a basic configurations and typical settings to suit abasic application. The basic configuration provides:

One settings group only.

One IDMT characteristic (t> = standard inverse)

Instantaneous overcurrent (t>>=0)

Breaker failure protection with backtrip relay

CB maintenance alarm

Remote circuit breaker control

Section 2. CHANGING THE CONFIGURATION OF THE RELAY

2.1 System data (SD)

Select the system data column of the menu, enter the password and then step downto the cell containing the SD links. Press the [+] key to put the relays into settingmode and use the [F] key to step through the options. The option will be shown inabbreviated form on the top line of the display as each function link is selected.To select an option set the link to “1” with the [+] key and to deselect it set it to “0”with the [–] key.

The following options are available via links SD0 to SD8:

SD0 Rem ChgStg 1 = enable remote setting changes

SD1 Not used

SD2 Rem CB Ctrl 1 = enable remote control of circuit breaker

SD3 Rem ChgGrp 1 = enable remote change of setting group

SD4 En Grp2 1 = enable group 2 settings to be used

SD5 Auto Flag 1 = enable flags to reset automatically on loadrestoration

SD6 Auto Rec 1 = enable disturbance recorder reset on loadrestoration

SD7 Log Evts 1 = enable logic events to be stored

SD8 Alt Rec Reset 1 = enable alternative reset method for disturbancerecord.

When the selection has been completed continue to press the [F] key until theconfirmation display appears and confirm the selection.

Now step down the menu to cell [0004 Description] and enter a suitable name forthe configuration; a maximum of sixteen characters are available.

Step down one cell [0005 Plant Ref.], where a suitable reference can be enteredfor the plant that the relay is to protect. If the configuration is for a relay that is tobe applied to one particular circuit, then the reference by which the circuit isknown can be entered at this time; a maximum of sixteen characters are available.

Now move down the system data column to cell [0009 Freq] and set the frequencyto 50Hz or 60Hz (except for KCEU relays) as appropriate. This is an important


setting because it will be the default frequency used by the analogue/digitalconverter when appropriate signals are not available for frequency tracking.

If the address of the relay on the serial communication bus is known then it can beentered at this time. This cell is password protected on the series 2 relays.

This concludes the settings that can be entered in this menu column at this time.

2.2 Earth fault links (EF)

Select the column EARTH FAULT (1) and EF Links. Press the [+] key to put the relayinto setting mode and set the links to “1” that enable the required options availablevia links EF0 to EF6.

EF 0 Not used

EF 1 En Io>> 1 = enable earth fault stage 2

EF 2 En Io>>> 1 = enable earth fault stage 3

EF 3 Drn to> 1 = earth fault stage 1 directionalised

EF 4 Drn to>> 1 = earth fault stage 2 directionalised

EF 5 Drn to>>> 1 = earth fault stage 3 directionalised

EF 6 Io>> NoPeak 1 = no peak measurement for stage 2 earth faultelement

EF E RevIo>>> 1 = reverse direction of third earth fault stage (Io>>>)

The links EF3, EF4 and EF5 enable the three overcurrent stages Io>, Io>> andIo>>> to be selectively directionalised. If all three links EF3, EF4 & EF5 are set nondirectional then the forward start will also be non directional and the reverse startwill retain its normal function provided a directionalising voltage signal isavailable. The directional options are not be available on non directional KCGGovercurrent relays.

For KCGG relays the Io>>/Io>>> elements are responsive to peak measurementso that they respond faster, but they will be more sensitive to harmonic currents thatcreate peaks on the waveform. The “NoPeak” option can be selected for Io>>element, with link EF6, when the relay is required to be insensitive to harmonics.However, the “NoPeak” option is only provided for the Io>> setting. The KCEG/KCEU directional overcurrent relays do not respond to peak values and are notprovided with this link option.

When the selection has been completed continue to press the [F] key until theconfirmation display appears and then confirm the selection.

Next enter the time delay characteristic for the to> element.

Enter, or copy, the same settings into the EARTH FAULT (2) column if it is active.It is not essential that the links are set the same in both setting groups. For examplethe Io>>> element could be made available in group one and not in group twosettings.

Note: It would be wise to ensure the logic is such that an element that is to beswitched out in the alternative setting group is reset before the alternativesetting group is selected, or alternatively make a physical test to ensurethere are no latch-up problems.

A different time characteristic can be selected for to> in the second setting group,but it is not advisable to select inverse in one group and definite time in the other if


it is intended to dynamically switch between setting groups. If two different inversecurves are selected then the same register will be used for both. These registers arenot reset to zero when the setting group is changed unless the current falls belowthe set threshold.

2.3 Phase fault links (PF)

Select the PF Links under the PHASE FAULT (1) menu column heading and put therelay into setting mode by pressing the [+] key. Step through the function links withthe [F] key and set the links for the options required.

There are more options available for phase faults, but most of the additional onesare associated with voltage functions that are only available of the directionalrelays. The exceptions are the thermal characteristic which can be enabled bysetting PF0=1 and the broken conductor detection which is activated by settingPFC=1. The 2/3 logic is also required for the broken conductor detection, so setlink PF7=1 as well when using this function.

PF 0 En Therm 1 = enable thermal element

PF 1 En I>> 1 = enable stage 2 overcurrent

PF 2 Enable I>>> 1 = enable stage 3 overcurrent

PF 3 Drn t> 1 = stage 1 overcurrent directionalised

PF 4 Drn t>> 1 = stage 2 overcurrent directionalised

PF 5 Drn t>>> 1 = stage 3 overcurrent directionalised

PF 6 I>> NoPeak 1 = no peak measurement for stage 2 overcurrent

PF 7 I>>>=2/3 1 = 2 out of 3 phase elements to operate forI>>>/t>>> trip

PF 8 CB blk V< 1 = V< blocked when CB open

PF 9 V< any=1 1 = any phase undervoltage for trip0 = all phases undervolted for trip

PF A V< P-N=1 1 = V< measure phase/neutral voltage0 = V< measure line voltage

PF B SynPol=3.2 1 = synchronous polarising time extended to 3.2s

PF C Brkn Cond 1 = enable broken conductor logic

PF D En F< 1 = enable underfrequency element to initiate tAUX1

PF E RevI>>> 1 = reverse direction of third overcurrent stage

PF F All 2/3 1 = 2/3 logic applied to all phase outputs

The links PF3, PF4 and PF5 enable the three overcurrent stages I>, I>> and I>>>to be selectively directionalised. If all three links PF3, PF4 & PF5 are set nondirectional then the forward start will also be non directional and the reverse startwill retain its normal function provided a directionalising voltage signal isavailable. The directional options are not available on non directional KCGGovercurrent relays.

For KCGG relays the I>>/I>>> elements are responsive to peak measurement sothat they respond faster, but they will be more sensitive to harmonic currents thatcreate peaks on the waveform. The “NoPeak” option can be selected for I>>element, with link PF6, when the relay is required to be less sensitive to harmonics.


However, the “NoPeak” option is only provided for the I>> setting. The KCEG/KCEU directional overcurrent relays do not respond to peak values and are notprovided with this link option.


Next enter the time delay characteristic for the t> element.

Enter, or copy, the same settings into the PHASE FAULT (2) column if it is active.It is not essential that the links are set the same in both setting groups. For examplethe I>>> element could be made available in group one and not in group twosettings.

Note: It would be wise to check that an element that is to be switched out in thealternative setting group is reset before the alternative setting group isselected, or alternatively make a physical test to ensure there are no latch-up problems.

A different time characteristic can be selected for t> in the second setting group,but it is not advisable to select inverse in one group and definite time in the other ifit is intended to dynamically switch between setting groups. If two different inversecurves are selected then the same register will be used for both and these registerswill not be reset to zero when the setting group is changed unless the current isbelow the set threshold.

2.4 Logic links (LOG)

The Logic Links under the LOGIC menu column heading customise the auxiliaryfunctions of the relay. Put the relay into setting mode by pressing the [+] key.Step through the function links with the [F] key and set the links for the optionsrequired.

LOG0 CB Rec 1 = enable CB records to be generated;0 = inhibit CB records.

LOG1 CB1*1=0 1 = sum of currents; 0 = sum of current squared.

LOG2 BF blk Start 1 = enable breaker fail to reset start relays.

LOG3 Aux2=I< 1 = enable I< to initiate timer tAUX2 (loss of loadfunction).

LOG4 Aux2=/Io< 1 = enable tAUX2 to start when Io exceeds Io< .

LOG5 tAUX3 Grp2 1 = Group 2 settings selected whilst tAUX3 is givingan output.

LOG6 tAUX2-tAUX3 1 = enable tAUX2 to delay pick-up of tAUX3.

LOG7 Latch Strt 1 = enable start flags to be latched.

LOG8 Hold Grp2 1 = manual selection of group 2 settings.

LOG9 Rst CBclose 1 = enable a trip to terminate the CB close pulse

LOGA Log Rly7 1 = enable relay RLY7 to initiate latch flags and logrecords

LOGB tAUX3=DDO 1 = tAUX3 delayed on drop-off0 = delayed on pick-up



Set the breaker failure protection time delay tBF.

Set the circuit breaker close and trip pulse time delays tCLOSE and tTRIP.

Select the default display that appears on start-up.

2.5 Preferred use of logic inputs

The following table is not mandatory, but it is suggested that it is followed wherepossible so that different schemes will use the a particular logic input for the sameor similar function.

L0 Stg grp2 [change setting group]

L1 Blk t>>/to>> [Block instantaneous low set from autoreclose]

L2 Blkt>>>/to>>> [Block overcurrent for busbar/unit feeder protection]

L3 EXT TRIP [external trip input from other protection]

L4 AUX2 [Auxiliary input to initiate timer tAUX2/CLP]

L5 AUX3 [Auxiliary input to initiate timer tAUX3/CLP]

L6 CB closed [indication that CB is closed]

L7 CB open [indication that CB is open]

2.6 Preferred use of output relays

The following table is not mandatory, but it is suggested that it is followed wherepossible so that different schemes will use a particular output relay for the same orsimilar function.

RLY0 START [earth fault start or combined phase and earth forwardstart]

RLY1 START [phase start or combined phase and earth reverse start]

RLY2 AR INITIATE [any function assigned to initate autoreclose]

RLY3 TRIP [any protection function assigned to trip the circuitbreaker]

RLY4 ALARM [Any function assigned to produce an alarm]

RLY5 BACKTRIP [Output to backtrip for breaker fail]

RLY6 CB close [in response to a remote command]

RLY7 CB trip [in response to a remote command]


Section 3. OVERCURRENT AND EARTH FAULT PROTECTION

Three independent time delayed overcurrent stages are provided for each phaseand residual current input. In addition there is an undercurrent function associatedwith each of these currents and in some instances a thermal overcurrentcharacteristic is provided. The settings are marked I>/t>; I>>/t>>; I>>>/t>>>; I<and Ith>/TC; shown appropriately in the diagram below. These settings affect allthree phases equally.

The earth fault elements have similar settings marked Io>/to>; Io>>/to>>; Io>>>/to>>> and Io<; there being no thermal element associated with this input.

Both the peak value and the Fourier derived rms value of the power frequencycomponent of the fault current are used to derive the protection functions.Each value has its own associated characteristics that can be used to advantage.For example, a change in the peak value may be detected in one half cycle of faultcurrent and so this measurement is used for the undercurrent elements to obtain thefast reset required by breaker fail applications. The Fourier derived values areparticularly useful for earth fault applications due to their high rejection ofharmonic currents, in particular the third harmonic. Fourier values are also used forall measurements where a phase angle reference is required.

Figure 1: Available overcurrent characteristics and their settings

t>>>I<

Time

I>>>

Current

I>

I>>

t>

TC

Ith>

t>>


Section 4. FIRST STAGE OVERCURRENT ANDEARTH FAULT LOGIC

The following diagram shows the logic associated with the first earth fault andovercurrent stages. When the residual current exceeds the Io> threshold andprovided that no logic inputs selected in the input mask [0A01 Blk to>] areenergised, the time delay to> will start to time out. When the delay time expiresthe output relays selected in the relay mask [0B03 to>] will be energised, causingthem to pick-up.

If a logic input selected in mask [0A01 BLK to>] is energised then the time delaywill be blocked and held reset.

Figure 2: First stage overcurrent and earth fault logic.

Similar logic is provided for the phase fault overcurrent protection and here aseparate overcurrent threshold and time delay is used for each phase, but thesame settings for I> and t> will apply to the elements on all three phases. Aseparate relay mask is provided for each phase so that a differrent output relaycan be assigned to each phase output and/or the same output relays to all threephases.

4.1 Start function

As soon as the Io> threshold is exceeded an instantaneous output is available viarelay mask [0B01 Io>]. This is used to indicate that the protection has detected anearth fault and that the time delay to> has started. This time delay can be blockedby energising a logic input assigned in the input mask [0A01 Blk to>]. If thisblocking input is energised by the start output from a downstream relay thenoperation will be blocked only if the relay nearer to the fault can clear the fault.This is the principle known as “Blocked Overcurrent Protection”, described morefully in a later section.

The phase element is also provided with a start output via mask [0B06 I>] and ablocking input via mask [ØAØ4 Blk t>]. The start outputs for both the phase andearth fault elements are gated with a blocking signal, the function of which isdescribed in the Section 4.8.1 Breaker failure protection.

The time delayed output is via mask [0B03 to>] for the earth faults and for phasefaults masks [0B08 tA>], [0B09 tB>] and [0B0A tC>] provide separate outputs foreach of the phase elements.

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

I>

BLK t>¯A¯4

Io>

+ 0A01 BLK to>

Blocking signal from breaker fail protection

≥1

&

&

t>

to>

I> START0B067 6 5 4 3 2 1 0&

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

tC>

tB>

tA>

0B0A

0B09

OBO8

7 6 5 4 3 2 1 0&

7 6 5 4 3 2 1 0

Io> START0B01

0B03 to> Ð


4.2 Definite time

The first stage can be selected have a definite time characteristic. The operationtime will be the set time for the time delay to> or t>, plus the operation time of theoutput relay and the time taken to detect the overcurrent condition.

The same register is used for the time delay t> in both setting groups and the timeris not reset when switching from one setting group to the other. Thus switching fromthe setting group with a long time setting to that with a short time setting may resultin an instantaneous trip if the shorter time setting had already elapsed.

4.3 Inverse time curves

Alternatively, the first stage can be selected to have a current dependent inversetime characteristic. The operation time is given accurately by a mathematicalexpression, into which the constants for the selected characteristic must beinserted.

Nine inverse time characteristics are available and the general mathematicalexpression for the curves is:

t = TMS secondsk

Ð1IIs

a + c

where TMS = Time Multiplier (0.025 to 1.5 in step 0.025)

I = Fault current

Is = Overcurrent setting

k, c, a = Constants specifying curve

Curve No. Description Name IEC Curve k c a

0 Definite Time DT – 0 0 to 100 11 Standard Inverse SI30xDT A 0.14 0 0.022 Very Inverse VI30xDT B 13.5 0 13 Extremely Inverse EI10xDT C 80 0 24 Long Time Inverse LTI30xDT – 120 0 15 Moderately Inverse MI D 0.103 0.228 0.026 Very Inverse VI E 39.22 0.982 27 Extremely Inverse EI F 56.4 0.243 28 Short Time Inverse STI30xDT – 0.05 0 0.049 Rectifier Protection RECT – 45900 0 5.6

Although the curves tend to infinity at the setting current value (Is), the guaranteedminimum operation current is 1.05Is ±0.05Is for all inverse characteristic curves,except curve 9 for which the minimum operating current is 1.6Is±0.05Is(see section on rectifier protection).

Note: Definite time characteristic and the start functions operate at Is ±0.05Is.

Curves numbers 1, 2, 4, and 8 become definite time for currents in excessof 30 x Is. Curve 3 becomes definite time for currents above 10 x Is to giveextra time grading steps at high current levels.


4.4 Reset timer

A delayed reset is provided with the t>/to> time delays and the time set for thistimer determines the duration that the current must remain below the thresholdI>/Io> before the time delay register is reset to zero. There is an exception to thiswhen the protection trips, because for this condition the time registers t>/to> arereset immediately. For the majority of applications the reset delay could be set tozero. For others a more appropriate setting can be used and some examplesapplications are given later.

4.5 Matching the reset time response of an electromechanical relay

Figure 3: Matching electromechanical reset time

The reset characteristic of an electromechanical relay is inverse and the reset timercan be used to give the relay a reset characteristic which approximates to this asshown in the diagram.

It should be noted that the tRESET is not affected by the time multiplier setting andmust therefore be set to the required delay.

4.6 Protection against intermittent recurrent faults

This type of fault is also sometimes referred to as a pecking or flashing fault.A typical example of an intermittent recurrent fault would be one in a plasticinsulated cable where, in the region of the fault, the plastic melts and reseals thecable, extinguishing the fault but after a short time the insulation breaks downagain. The process repeats to give a succession of fault current pulses each ofincreasing duration with reducing intervals between, until the fault becomespermanent.

tReset

Is


Figure 4: Intermittent recurrent fault

When the reset time of the overcurrent relay is less than the interval between thefault current pulses, the relay will be continually reset and not be able to integrateup to the trip level until the fault becomes permanent. Having the reset time set togive as long a delay as possible, but less than that which would interfere withnormal operation of the protection and control system, will help to eliminate someless common health and safety problems.

Overcurrent relays in Midos K Range have provision for adjusting the reset delayto values between 0 and 60 seconds for timers t>/to>. Reset times of 60 secondsare most suited to cable applications where autoreclose is not generally permitted.For overhead lines with fast reclosing equipment, it can be an advantage to set thereset time to zero; this will ensure that all relays will have fully reset before areclosure takes place and that some relays will not be held part way towardsoperation as a result of the last fault.

When grading with electro-mechanical relays which do not reset instantaneously,the reset delay can be used to advantage to gain closer discrimination. In theseinstances the reset time should be set to a value less than the dead time setting ofany autoreclose relays on the system. Sensitive earth/ground fault relays will alsobenefit from having the reset time set as high as possible so that fault current pulsesare summated.

Any reset delay will give an improvement in the detection of intermittent faults.

4.7 Time graded protection

Inverse definite minimum time relays are time graded such that the relay nearer tothe fault operates faster than the relays nearer to the source. This is referred to asrelay co-ordination because if the relay nearest to the fault does not operate, thenext one back towards the source will trip in a slightly longer time. The timegrading steps are typically 400ms, the operation times becoming progressivelylonger with each stage.

Where difficulty is experienced in arranging the required time grading steps theuse of a blocked overcurrent scheme should be considered (described in a latersection).

Note: The dynamic range of measurement is typically 820 times minimum setting.

0.3s

0

Trip level

0.2s0A

2000A

3.0s 2.0s 0.5s


4.8 Dual rate inverse time curves

Figure 5: Dual rate curves

The same registers are used for the time delay in both setting group 1 and settinggroup 2. They are not reset when switching from one group to the other, unless thecurrent falls below the threshold, or a blocking input is asserted.

One of the other two time stages I>>, or I>>>, must be set in both setting groups,to the current level at which the curve is to change. When this current setting isexceeded, an output relay that is externally connected to energise a logic input willselect the second setting group. I>(2), the current setting in the second settinggroup, must be set to less than 95% of the I>>, the current at which thecharacteristic is switched, to ensure that the register does not reset.

The same TMS setting is advised for both setting groups, as an instantaneous tripmay occur when switching to a lower TMS setting if the shorter time setting hasalready elapsed.

Section 5. SECOND/THIRD STAGE OVERCURRENT andEARTH FAULT LOGIC

The second and third overcurrent and earth fault stages must be selected by settinglinks PF1, PF2, EF1 and EF2 =1 as appropriate for their associated settings toappear in the menu table. For these elements to operate the Fourier derived valueof current must exceed the set threshold, or the peak value of the current mustexceed twice the set threshold. This latter function ensures faster operation forcurrents above twice setting whilst ensuring negligible transient overreach.

The time delays for the second and third stage overcurrent elements can beblocked by the energisation a logic input. If the time delay has started it will bereset by the application of the blocking signal. Each phase fault and earth faultelement has its own independent time delay to ensure correct discrimination andfault indication.

t

I>(1)

I>(2)

I>>


Figure 6: Second and third stage overcurrent logic

5.1 Two out of three logic

The t>>> element is provided with a two out of three logic, selected by setting linkPF7=1. When selected, operation only occurs for phase/phase faults and doublephase to earth/ground faults. It will not operate for single phase earth/groundfaults.

5.2 Broken conductor logic

The Broken Conductor Detection feature is associated with t>>> element and isbased on the principle that if a conductor is broken there will be load current intwo phases, but not in all three.

The logic associated that provides this function is shown in Figure 6 above. It isenabled when links PF2, PFC and PF7 are each set to ‘1’. Link PF2 activates thethird overcurrent stage and when link PF7 is set to ‘1’ an output will be produced ifcurrent is flowing in only two phases for a time in access of the setting t>>>.Link PFC enables the undercurrent elements to block the operation of t>>> if currentis flowing in all three phases. Typically settings are, I< = 0.06In: I>>>= 0.08In forthis application to ensure positive discrimination.

An output relay can be allocated in the output mask [0B0C t>>>] for detection of abroken conductor. To latch the flags relay RLY3 must be assigned in this sameoutput mask and the flags will indicate the fault with a _ _ * for two of the threephases and exclude the letters identifying the phases if the current is below the I>threshold. The broken conductor will be in the phase for which no flags haveoperated, because the current is zero.

5.3 Transformer inrush currents

Either I>>/Io>>, or I>>>/Io>>> elements, may be used as high-set instantaneouselements. The design is such that they do not respond to the DC transientcomponent of the fault current. The principle of operation allows the currentsettings to be set down to 35% of the prospective peak inrush current that will betaken by a transformer when it is energised. To a first approximation the peakinrush is given by the reciprocal of the per unit series reactance of the transformer.

Use of the cold load pick up feature, to increase the time setting for theinstantaneous elements when energising the primary circuit, may be considered asa way of allowing lower current thresholds to be used.

7 6 5 4 3 2 1 0

&

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0BLK to>>

BLK to>>>

I>>>

PF2

10

10

I<

PFC

BLK t>>>

BLK t>>

I>>01

PF1

Io>>>0

0A06

0A05

EF2

10

EF1

Io>>

0A02

0A03

& >>to>

t>>

>t>

&

&

PF7

>2/3

0

1

& >to>

7 6 5 4 3 2 1 0

t>>>OBOC7 6 5 4 3 2 1 0

t>>7 6 5 4 3 2 1 0

0B0B

to>>>0B05

7 6 5 4 3 2 1 0to>>0B04

Stage 2Earth fault

Stage 3Earth fault

Stage 2Overcurrent

Broken conductorStage 3 Overcurrent

1

∞1

≥1

≥1


5.4 Sensitivity to harmonics

The sampling frequency of the digital/analogue converter is synchronised to thepower frequency by a frequency tracking algorithm. This improves both accuracyof measurement and the harmonic rejection. The tracking follows the analoguephase inputs with a preference to track the voltage inputs, but in their absence thecurrent inputs are tracked. When the signal levels are too small to track thesampling frequency defaults to the set system frequency. It is important that this hasbeen correctly set in menu cell 0009.

The fundamental component of the residual voltage and current is usually relativelysmall and this can result in the harmonic content being predominant. Frequencytracking does not take place on the residual signals because it can lock-in to a sub-harmonic of the predominant frequency resulting in a reduced harmonic rejectionlevel. An example where this would become a problem is when a transformer isenergise and an almost pure second harmonic current can appear in the neutralcircuit. With frequency tracking of this signal the harmonic rejection could fallsignificantly. For this application a multiphase relay is best suited as it will givemaximum harmonic rejection whilst tracking the phase quantities.

The I>>/Io>> and the I>>>/Io>>> elements in the KCGG relays respond to thepeak value and the fourier derived values. This allows them to respond morequickly to an overcurrent condition, but at the same time it reduces the harmonicrejection. The I>>/Io>> elements are each provided with a software link PF6/EF6that inhibits the peak measurement when they are set to ‘1’. If the Io>> element isused for sensitive earth fault applications it is advised that link EF6 is set to ‘1’.The KCEG directional relays do not respond to the peak values and so for themlinks PF6 and EF6 cannot be set.

5.5 Autoreclose inhibition of instantaneous low set

When overcurrent relays from the Midos K Range are used with autoreclose relaysthe I>>/Io>> elements may be used as low set instantaneous elements.The associated time delays t>>/to>> would be set to zero seconds to effect rapidfault clearance. Although the timer is set to zero, its output still may be blocked viaone of the logic inputs to the relay. Blocking this element instead of the trip path,with a contact of the autoreclose relay, will ensure correct flagging at all times.

Where lightning strikes are frequent, it can be an advantage to make the I>>/Io>> setting equal to I>/Io>, in order to detect the maximum number of transientfaults. It will also be advantageous to set SD5 = 1 so that the protection flagsautomatically reset after a successful reclose sequence.

5.6 Blocked overcurrent protection

This type of protection is applicable to radial feeder circuits where there is little orno back feed. For parallel feeders, ring circuits, or where there can be a back feedfrom generators, directional relays should be considered.

5.6.1 Blocked IDMT overcurrent

This application relies on the up-stream IDMT relay being blocked by the startoutput from a down-stream relay that detects the presence of fault current above itssetting. Thus both the up-stream and down-stream relays can then have the samecurrent and time settings and grading will be automatically provided by theblocking feature. If the breaker fail protection is selected, the block on the up-stream relay will be released if the down-stream circuit breaker fails to trip.


Thus for a fault below relay C, the start output from relay C will block operation ofrelay B and the start output of relay B will block operation of relay A. Hence allthree relays could have the same time and current settings and the grading wouldbe obtained by the blocking signal received from a relay closer to the fault. Thisgives a constant, close time grading, but there will be no back-up protection in theevent of the pilots being short circuited.

Figure 7: Blocked IDMT overcurrent

5.6.2 Blocked short time overcurrent

Reduced fault clearance times and increased security can be obtained by usingblocked short time overcurrent protection. For this the I>>/t>> and the Io>>/to>>elements are used with their current threshold set above the transient load level andsetting t>>/to>> to 80ms for non-directional relays. This time delay is for worstcase conditions and may be reduced, depending on the system X/R and maximumfault level.

A

B

C


The time delays t>>/to>> are arranged to be blocked by the start output of thedownstream relay when the downstream relay detects a fault current flowing.The short time delay is essential to ensure that the blocking signal will be receivedby the upstream relay before operation can occur.

The inverse time overload elements should be graded in the normal way forcascade operation and to provide overload and backup protection. The short timeelements, operating in the blocking mode, then provide an instantaneous zone ofprotection and again the breaker fail feature can be used to advantage.On detection of a breaker failure condition the start output would be reset toremove the block from the upstream relay, allowing the upstream relay to trip itsbreaker to clear the fault.

Overcurrent relays are adequate for non-cascade operation on radial circuits, butfor ring circuits, or where there are parallel feeds, it will be necessary to usedirectionalised overcurrent relays.

5.7 Protection of busbars on radial system

This is simply achieved on radial circuits by setting for the short time lags(t>>/to>>) of the relay on the incoming feeder 80ms for non-directional relays,and blocking these time delays when the start output of any relay on the loadcircuits detects fault current flowing from the busbar to a feeder. The 80ms timedelay is for worst case conditions and may be reduced, depending on the systemX/R and maximum fault level. Feedback from regenerative loads must be less thanthe relay setting.

The protection can be enhanced by arranging for the internal breaker fail circuitsof the feeder relays to backtrip the incoming circuit breaker and/or adding theback-up transfer tripping arrangement. The use of a dual powered relay on theincoming feeder can also be considered to provide dead substation protection.These topics are described more fully in other sections.

Figure 8: Blocked overcurrent for busbar protection

Feeder 3

Incomer

Feeder 1

F2

Feeder 2

KCGG

F3

KCGG

F1

KCGG

F4

KCGG

Feeder 4

F5

KCEG

142 142

Block short time overcurrent

142142

Back trip242


5.8 Points to consider with blocking schemes

It is possible to separate the phase and earth fault start outputs and use them toblock the respective elements of the upstream relay. However, if this is done thenthe effect of current transformer saturation during phase faults has to beconsidered. If the current transformers transiently saturate on one of the circuitsthen a spill current is produced in the neutral circuit of the current transformers.This can result in one of two effects:

– The current exceeds the threshold of the earth/ground fault element then it willattempt to trip if it does not receive a blocking signal from a down stream relay.This will be an incorrect operation that may trip more circuits than necessary.

– As a result of spill current, an earth/ground fault element gives a blockingsignal to the relay on the in-feed for a short duration.

The first of these problems can be lessened by increasing the time setting of to>>,but this will reduce the benefits of blocked overcurrent schemes. The solution toconsider is to block the phase and earth fault trip elements with the phase andearth fault start elements of the downstream relays, but prevent blocking of thephase fault trip elements under transient current transformer saturation conditions.This will be most easily achieved by setting the earth fault element polarisingvoltage threshold (Vop) above the maximum expected zero sequence voltageoccurring under healthy conditions, thus preventing the earth fault elements on theincoming feeder relay producing a blocking signal under transient CT saturationconditions.

The second effect may not be a problem at all if the transient spill current only lastsa short time, as the added delay caused by a spurious blocking signal will stabilisethe protection for only a short time. If this is seen as a problem then the use of astabilising resistor could be considered.

Figure 9: Back-up transfer trip scheme

Trip

WatchdogContacts

WatchdogContacts

Watchdogrepeat relay

t>>>

t>>

Incomer

Feeder2

Feeder4

Feeder1

Feeder2

Feeder3

Feeder1

Feeder4

Feeder3

t>> set to 60ms

t>>> set to 260ms

Incomer

+ Ðrelays


5.9 Back-up transfer tripping scheme

In this application a trip from the relay on the incoming feeder can be diverted viathe watchdog contacts of a failed relay to the circuit breaker on that feeder. Thus afault on an outgoing feeder can be cleared by tripping the feeder circuit breakereven though the relay on that circuit has failed. Without this feature the fault wouldonly have been cleared by tripping the circuit breaker on the incoming feeder andthus losing the total busbar load.

Consider the radial feed arrangement shown in the diagram. The protection relayon the incomer provides two additional time delayed outputs: t>> with an 80msdelay if the downstream feeder relays are non-directional, or 200ms if they aredirectional, and t>>> with a delay of t>> plus grading margin. The t>> delay is forworst case conditions and may be reduced, depending on the system X/R andmaximum fault level. The t>> output contact is wired through a normally opencontact on the watchdog repeat relay, to the trip relay for the circuit breaker on thein-feed. The t>>> output is wired directly to the trip relay for the circuit breaker onthe in-feed.

With all the relays in a healthy state, the watchdog repeat relay will be energisedand for a busbar fault the circuit breaker on the incoming circuit will be tripped byt>>. For a fault on any of the outgoing feeders t>> and t>>> of the relay on theincoming circuit will be blocked by the start contact of the overcurrent relay on theoutgoing feeder which is carrying the fault current. The circuit carrying the faultcurrent will be tripped by the overcurrent relay on that circuit.

In the event of any relay on the outgoing circuits becoming defective, thewatchdog repeat relay drops off to give an alarm and to transfer the t>> trip fromthe incoming circuit breaker to the buswire connected, via the watchdog breakcontact of each relay on the outgoing feeders, to the appropriate circuit breaker.Thus the trip will be transferred to the circuit breaker with the failed relay and so afault on that circuit will be cleared without tripping the busbar. For a busbar faultthe incoming circuit breaker will be tripped by t>>> after a short delay. For faultson any healthy outgoing feeder both t>> and t>>> of the incoming feeder will beblocked and correct discrimination will be obtained with only the faulted feederbeing tripped.

5.10 High impedance protection

The application of the KCGG numerical overcurrent relay as differential protectionfor machines, power transformers and busbar installations is based on the highimpedance differential principle, offering stability for any type of fault occurringoutside the protected zone and satisfactory operation for faults within the zone.

A high impedance relay is defined as a relay or relay circuit whose voltage settingis not less than the calculated maximum voltage which can appear across itsterminals under the assigned maximum through fault current condition.

It can be seen from Figure 1 that during an external fault the through fault currentshould circulate between the current transformer secondaries. The only current thatcan flow through the relay circuit is that due to any difference in the currenttransformer outputs for the same primary current. Magnetic saturation will reducethe output of a current transformer and the most extreme case for stability will be ifone current transformer is completely saturated and the other unaffected. Thiscondition can be approached in busbar installations due to the multiplicity ofinfeeds and extremely high fault level. It is less likely with machines or powertransformers due to the limitation of through fault level by the protected unit’s


impedance, and the fact that the comparison is made between a limited number ofcurrent transformers. Differences in current transformer remanent flux can, however,result in asymmetric current transformer saturation with all applications.

Calculations based on the above extreme case for stability have become acceptedin lieu of conjunctive scheme testing as being a satisfactory basis for application.At one end the current transformer can be considered fully saturated, with itsmagnetising impedance ZMB short circuited while the current transformer at theother end, being unaffected, delivers its full current output. This current will thendivide between the relay and the saturated current transformer. This division will bein the inverse ratio ofRRELAY CIRCUIT to (RCTB + 2RL) and, if RRELAY CIRCUIT is high compared with RCTB + 2RL,the relay will be prevented from undesirable operation, as most of the current willpass through the saturated current transformer.

To achieve stability for external faults, the stability voltage for the protection (Vs)must be determined in accordance with formula 1.The setting will be dependent upon the maximum current transformer secondarycurrent for an external fault (If) and also on the highest loop resistance value fromthe relaying point (RCT + 2RL).The stability of the scheme is also affected by the characteristics of the differentialrelay and the value of K in the expression takes account of this. One particularcharacteristic that affects the stability of the scheme is the operating time of thedifferential relay. The slower the relay operates the longer the spill current canexceed its setting before operation occurs and the higher the spill current that canbe tolerated. For the KCGG relay I> element the value of K is 0.5 as shown informula 2.

Vs > KIf(RCT + 2RL) (1)

Vs > 0.5If(RCT + 2RL) (2)

where RCT = current transformer secondary winding resistance

RL = maximum lead resistance from the current transformer to therelaying point

If = maximum secondary external fault current

K = a constant affected by the dynamic response of the relay

Figure 10: Principle of high impedance protection

CTA

ZMA

RCTA

RL

RL

CTB

ZMB

RCTB

RL

RL

Protectedunit

RRELAY CIRCUIT


Note: When high impedance differential protection is applied to motors orreactors, there is no external fault current. Therefore, the locked rotorcurrent or starting current of the motor, or reactor inrush current, should beused in place of the external fault current.

To obtain high speed operation for internal faults, the knee point voltage, VK, ofthe CTs must be significantly higher than the stability voltage, Vs. This is essentialso that the operating current through the relay is a sufficient multiple of the appliedcurrent setting. Ideally a ratio of VK ≥5Vs would be appropriate, but where this isnot possible refer to the Advanced Application Requirements for Through FaultStability.This describes an alternative method whereby lower values of Vs may be obtained.

Typical operating times for different VK/Vs ratios are shown in the following table:

VK/Vs 12 6 3 2

Typicaloperating 30 40 50 60time (ms)

These times are representative of a system X/R ratio of 40 and a fault level of 5Isto 10Is. Lower values of X/R and higher fault currents will tend to reduce theoperating time.

The kneepoint voltage of a current transformer marks the upper limit of the roughlylinear portion of the secondary winding excitation characteristic. This is definedexactly in British practice as that point on the excitation curve where a 10%increase in exciting voltage produces a 50% increase in exciting current.

The current transformers should be of equal ratio, of similar magnetisingcharacteristics and of low reactance construction. In cases where low reactancecurrent transformers are not available and high reactance ones must be used,it is essential to use the reactance of the current transformer in the calculations forthe voltage setting. Thus, the current transformer impedance is expressed as acomplex number in the formRCT + jXCT. It is also necessary to ensure that the exciting impedance of the currenttransformer is large in comparison with its secondary ohmic impedance at therelay setting voltage.

In the case of the high impedance relay, the operating current is adjustable indiscrete steps.The primary operating current (Iop) will be a function of the current transformerratio, the relay operating current (Ir), the number of current transformers in parallelwith a relay element (n) and the magnetising current of each current transformer(Ie) at the stability voltage (Vs). This relationship can be expressed as follows:

Iop = (CT ratio) x (Ir + nIe) (3)

In order to achieve the required primary operating current with the currenttransformers that are used, a current setting (Ir) must be selected for the highimpedance relay, as detailed above. The setting of the stabilising resistor (RST) mustbe calculated in the following manner, where the setting is a function of the relayohmic impedance at setting (Rr), the required stability voltage setting (Vs) and therelay current setting (Ir).

RST =VsIr

Rr (4)


Note: The auxiliary powered KCGG ohmic impedance over the whole settingrange is small, 0.06Ω (1A) and 0.006Ω (5A) and so can be ignored.Therefore:

RST =VsIr

(5)

5.10.1 Use of metrosil non-linear resistors

When the maximum through fault current is limited by the protected circuitimpedance, such as in the case of generator differential and power transformerrestricted earth fault protection, it is generally found unnecessary to use non-linearvoltage limiting resistors (Metrosils). However, when the maximum through faultcurrent is high, such as in busbar protection, it is more common to use a non-linearresistor (Metrosil) across the relay circuit (relay and stabilising resistor). Metrosilsare used to limit the peak voltage developed by the current transformers, underinternal fault conditions, to a value below the insulation level of the currenttransformers, relay and interconnecting leads, which are able to withstand 3000Vpeak.

The following formulae should be used to estimate the peak transient voltage thatcould be produced for an internal fault. This voltage is a function of the currenttransformer kneepoint voltage and the prospective voltage that would be producedfor an internal fault if current transformer saturation did not occur. Note, theinternal fault level, I'f , can be significantly higher than the external fault level, If ,on generators where current can be fed from the supply system and the generator.

Vp = 2 2VK (Vf VK) (6)

Vf = I'f (RCT + 2RL + RST + Rr) (7)

where Vp = peak voltage developed by the CT under internal faultconditions.

Vk = current transformer knee-point voltage.

Vf = maximum voltage that would be produced if CT saturation didnot occur.

I'f = maximum internal secondary fault current.

RCT = current transformer secondary winding resistance.

RL = maximum lead burden from current transformer to relay.

RST = relay stabilising resistor.

Rr = Relay ohmic impedance at setting.

When the value of Vp is greater than 3000V peak, non-linear resistors (Metrosils)should be applied. These Metrosils are effectively connected across the relaycircuit, or phase to neutral of the ac buswires, and serve the purpose of shuntingthe secondary current output of the current transformer from the relay circuit inorder to prevent very high secondary voltages.

These Metrosils are externally mounted and take the form of annular discs, of152mm diameter and approximately 10mm thickness. Their operatingcharacteristics follow the expression:

V = CI0.25 (8)

where V = Instantaneous voltage applied to thenon-linear resistor (Metrosil)


C = constant of the non-linear resistor (Metrosil)

I = instantaneous current through the non-linear resistor (Metrosil)

With a sinusoidal voltage applied across the Metrosil, the RMS current would beapproximately 0.52x the peak current. This current value can be calculated asfollows:

I(rms) = 0.52Vs(rms) x 2 4

C (9)

where Vs(rms) = rms value of the sinusoidal voltage applied across the Metrosil.

This is due to the fact that the current waveform through the Metrosil is notsinusoidal but appreciably distorted.

For satisfactory application of a non-linear resistor (Metrosil), it’s characteristicshould be such that it complies with the following requirements:

At the relay voltage setting, the non-linear resistor (Metrosil) current should be aslow as possible, but no greater than approximately 30mA rms for 1A currenttransformers and approximately 100mA rms for 5A current transformers.

The metrosil units normally recommended for use with 1A CTs are as follows:

Stability voltage Recommended metrosil type

Vs (V) rms Single pole Triple pole

Up to 125V 600A/S1/S256 600A/S3/I/S802C = 450 C = 450

125-300V 600A/S1/S1088 600A/S3/I/S1195C = 900 C = 900

The metrosil units normally recommended for use with 5A CTs and single pole relays are asfollows:

Secondary Recommended metrosil type

internal fault Relay stability voltage, Vs (V) rms

Current(A) rms Up to 200V 250V 275V 300V

50A 600A/S1/S1213 600A/S1/S1214 600A/S1/S1214 600A/S1/S1223C = 540/640 C = 670/800 C = 670/800 C = 740/870

100A 600A/S2/P/S1217 600A/S2/P/S1215 600A/S2/P/S1215 600A/S2/P/S1196C = 470/540 C = 570/670 C = 570/670 C = 620/740

150A 600A/S3/P/S1219 600A/S3/P/S1220 600A/S3/P/S1221 600A/S3/P/S1222C = 430/500 C = 520/620 C = 570/670 C = 620/740

The single pole Metrosil units recommended for use with 5A CTs can also be usedwith triple pole relays and consist of three single pole units mounted on the samecentral stud but electrically insulated from each other. A ‘triple pole’ Metrosil typeand the reference should be specified when ordering. Metrosil units for higherstability voltage settings and fault currents can be supplied if required.


5.10.2 The KCGG

The KCGG142 is a numerical 3 phase overcurrent and earth fault relay with 3stages of phase and earth fault protection, I>/Io>, I>>/Io>> and I>>>/Io>>>which can be used for 3 phase differential protection or restricted earth fault (REF)protection. The KCGG122 is a numerical single phase overcurrent and earth faultrelay with the same 3 stages of phase and earth fault protection, which can beused for REF protection only. It is recommended that the I> element is used as themain protection element for 3 phase differential protection and the Io> element forrestricted earth fault applications. This is because the I>/Io> elements haveincreased through fault stability compared to the I>>/Io>> and I>>>/Io>>>elements. The I>/Io> elements operate when the Fourier value exceeds thethreshold setting and the positive and negative peak values exceed 90% of thethreshold setting. The I>>/Io>> and I>>>/Io>>> elements operate when theFourier derived values exceeds the threshold setting or where the peak of any halfcycle exceeds twice the set threshold. Since the differential spill current is likely tocontain a dc offset level, the positive and negative peaks will have differentamplitudes and so the I>/Io> element is more stable. The time delay characteristicshould be selected to be definite time and with a setting of zero seconds.

The output relay that is to trip the circuit breakers must be allocated in the relaymasks for t>A, t>B and t>C. Any relay allocated in these relay masks will dwell inthe closed state for a minimum of 100 milliseconds, even if fleeting operation ofthe protection should occur, ensuring positive operation of the circuit breaker, ortrip relay. It is not advised that the start outputs from I> are used because they donot have this in-built minimum contact dwell.

Separate output relays may be allocated to each phase trip if it is required to havephase segregated outputs. However, the three relay masks, t>A, t>B and t>C mustalso be assigned to relay RLY3, for fault records to be generated. Phaseinformation will be included in the fault flags.

The Io>>/Io>>>/I>>/I>>> elements not being used should be disabled by settingthe phase and earth fault function links PF1, PF2, EF1 and EF2 to 0.

Setting ranges of I>/Io> elements are:

I> 0.08 – 3.2In

Io> 0.005 – 0.8In

The ohmic impedance (Rr) of the auxiliary powered KCGG over the whole settingrange is 0.06Ω for 1A relays and 0.006Ω for 5A relays ie. independent ofcurrent. To comply with the definition for a high impedance relay, it is necessary, inmost applications, to utilise an externally mounted stabilising resistor in series withthe relay.

The standard values of the stabilising resistors normally supplied with the relay, onrequest, are 220Ω and 47Ω for 1A and 5A relay ratings respectively. Inapplications such as busbar protection, where higher values of stabilising resistorare often required to obtain the desired relay voltage setting, non-standard resistorvalues can be supplied. The standard resistors are wire wound, continuouslyadjustable and have a continuous rating of 145W.


5.10.3 Applying the KCGG

The recommended relay current setting for restricted earth fault protection is usuallydetermined by the minimum fault current available for operation of the relay andwhenever possible it should not be greater than 30% of the minimum fault level.For busbar protection, it is considered good practice by some utilities to set theminimum primary operating current in excess of the rated load. Thus, if one of thecurrent transformers becomes open circuit the high impedance relay does notmaloperate.

The Io> earth fault element in the KCGG142 with it’s low current settings can beused for busbar supervision. When a CT or the buswires become open circuitedthe 3 phase currents will become unbalanced and residual current will flow.Hence, the Io> earth fault element should give an alarm for open circuit conditionsbut will not stop a maloperation of the differential element if the relay is set belowrated load. Whenever possible the supervision primary operating current shouldnot be more than 25 amps or 10% of the smallest circuit rating, whichever is thegreater. The earth fault element (Io>) should be connected at the star point of thestabilising resistors, as shown in Figure 9. The time delay setting for the supervisionelements (to>) should be at least 3 seconds to ensure that spurious operation doesnot occur during any through fault. This earth fault element will operate for anopen circuit CT on any one phase, or two phases, but not necessarily for a fault onall three when the currents may sumate to zero. The supervision may besupplemented with a spare phase protection stage (I>>>) set to the same setting asthe Io> element or its lowest setting, 0.08In, if the Io> supervision setting is lessthan 0.08In. Note that the Io current should be checked when the busbar is underload. This can be viewed in the Measurements 1 menu in the relay. It is importantthat the Io> threshold is set above any standing Io unbalance current.The supervision element should be used to energise an auxiliary relay with handreset contacts connected to short circuit the buswires.This renders the busbar zone protection inoperative and prevents thermal damageto the Metrosil. Contacts may also be required for busbar supervision alarmpurposes.

It is recommended that the dual powered KCEG242 relay is not used fordifferential protection because of the start-up time delay when powered from theCTs alone, approximately 200ms. Also, the minimum setting of the phaseovercurrent elements, 0.4In, would limit its application for differential protection.

Figures 3 to 9 show how high impedance relays can be applied in a number ofdifferent situations.

5.10.3.1 Advanced application requirements for through fault stability

When Vs from formula 2 becomes too restrictive for the application, the followingnotes should be considered. The information is based on the transient and steadystate stability limits derived from conjunctive testing of the relay. Using thisinformation will allow a lower stability voltage to be applied to the relay, but thecalculations become a little more involved.

There are two factors to be considered that affect the stability of the scheme. Thefirst is saturation of the current transformers caused by the dc transient componentof the fault current and the second is steady state saturation caused by thesymmetrical ac component of fault current only.


5.10.3.2 Transient stability limit

To ensure through fault stability with a transient offset in the fault current therequired voltage setting is given by:

Vs = 40 + 0.05RST +0.04If(RCT + 2RL) (10)

If this value is lower than that given by formula 2 then it should be used instead.

Vs and RST are unknowns in equation (10). However, for a relay current setting Ir,the value of RST can be calculated by substituting for Vs using equation (5), Vs = IrRST.

RST Ir = 40 + 0.05RST +0.04If(RCT+ 2RL) (11)

5.10.3.3 Steady state stability limit

To ensure through fault stability with non offset currents:

(RCT+ 2RL) must not exceed(VK + Vs)/If. (12)

5.10.4 Typical setting examples

5.10.4.1 Restricted earth fault protection

The correct application of the KCGG as a high impedance relay can best beillustrated by taking the case of the 11000/415V, 1000kVA, X = 5%, powertransformer shown in Figure 10, for which restricted earth fault protection isrequired on the LV winding. CT ratio is 100/5A.

5.10.4.2 Stability voltage

The power transformer full load current

= 1000 x 103

3 x 415

= 1391A

Maximum through fault level (ignoring source impedance)

= 1005

x 1391

= 27820A

Required relay stability voltage (assuming one CT saturated)

= 0.5If (RCT + 2RL)

= 0.5 x 27820

x 51500 (0.3 + 0.08)

= 17.6V


5.10.4.3 Stabilising resistor

Assuming that the relay effective setting for a solidly earthed power transformer isapproximately 30% of full load current, we can choose a relay current setting, Io>= 20% of 5A ie. 1A. On this basis the required value of stabilising resistor is:

VsIr

RST =

17.61

=

= 17.6 ohms

5A rated KCGG relays can be supplied, on request, with stabilising resistors thatare continuously adjustable between 0 and 47Ω.Thus, a stabilising resistance of 17.6Ω can be set using the standard suppliedresistor.

5.10.4.4 Current transformer requirements

To ensure that internal faults are cleared in the shortest possible time the knee pointvoltage of the current transformers should be at least 5 times the stability voltage,Vs.

VK = 5Vs

= 5 x 17.6

= 88V

The exciting current to be drawn by the current transformers at the relay stabilityvoltage, Vs, will be:

Ie < Is Irn

where Is = relay effective setting

= 30100

x 1391 x 51500

= 1.4A

Ir (Io>) = relay setting

= 1A

n = number of currenttransformers in parallelwith the relay

= 4

∴ Ie @ 17.6V <1.4 1

4< 0.1A

The time delay setting of the to> element should be set to 0s.

The Io>>/Io>>>/I>>/I>>> elements not used should be disabled by setting thephase and earth fault function links PF1, PF2, EF1 and EF2 to 0. Note, the phaseovercurrent elements not used for restricted earth fault protection could be used toprovide normal overcurrent protection.


5.10.4.5 Metrosil non-linear resistor requirements

If the peak voltage appearing across the relay circuit under maximum internal faultconditions exceeds 3000V peak then a suitable non-linear resistor (Metrosil),externally mounted, should be connected across the relay and stabilising resistor,in order to protect the insulation of the current transformers, relay andinterconnecting leads. In the present case the peak voltage can be estimated bythe formula:

Vp = 2 2VK (Vf VK)

where VK = 88V (In practice this should be the actual current transformer kneepointvoltage, obtained from the current transformer magnetisation curve).

Vf = If(RCT + 2RL RST + Rr)

= 27820 x 51500

x

(0.3 + 0.08 + 17.6)

= 92.7 x 17.98

= 1667V

Therefore substituting these values for VK and Vf into the main formula, it can beseen that the peak voltage developed by the current transformer is:

Vp = 2 2VK (Vf VK)

= 2 2 x 88 x (1667 88)

= 1054V

This value is well below the maximum of 3000V peak and therefore no Metrosilsare required with the relay. If, on the other hand, the peak voltage VP given by theformula had been greater than 3000V peak, a non-linear resistor (Metrosil) wouldhave to be connected across the relay and the stabilising resistor.The recommended non-linear resistor type would have to be chosen in accordancewith the maximum secondary internal fault current and the voltage setting.

5.10.5 Busbar protection

A typical 132kV double bus generating station is made up of two 100MVAgenerators and associated step-up transformers, providing power to the highvoltage system, by means of four overhead transmission lines, shown inFigure 2. The main and reserve busbars are sectionalised with bus section circuitbreakers.The application for a high impedance circulating current scheme having 4 zonesand an overall check feature, is as follows:

The switchgear rating is 3500MVA, the system voltage is 132kV solidly earthedand the maximum loop lead resistance is 4 ohms. The current transformers are ofratio 500/1 amp and have a secondary resistance of 0.7 ohms.

5.10.5.1 Stability voltage

The stability level of the busbar protection is governed by the maximum throughfault level which is assumed to be the switchgear rating. Using the switchgearrating allows for any future system expansion.

= 3500 x 106

3 x 132 x 103 = 15300A


Required relay stability voltage (assuming one CT is saturated)

= 0.5 If (RCT + 2RL)

= 0.5 x 15300500

(0.7 + 4)

= 72V

5.10.5.2 Current setting

The primary operating current of busbar protection is normally set to less than 30%of the minimum fault level. It is also considered good practice by some utilities toset the minimum primary operating current in excess of the rated load. Thus, if oneof the CTs becomes open circuit the high impedance relay does not maloperate.

The primary operating current should be made less than 30% of the minimum faultcurrent and more than the full load current of one of the incomers. Thus, if one ofthe incomer CTs becomes open circuit the differential protection will notmaloperate. It is assumed that 30% of the minimum fault current is more than thefull load current of the largest circuit.

Full load current

= 100 x 103

3 x 132= 438A

5.10.5.3 Discriminating zone

Magnetising current taken by each CT at 72V = 0.072A

Maximum number of CTs perzone = 5

Relay current setting,Ir(I>) = 400A = 0.8In

Relay primary operating current,Iop = CT ratio x (Ir + nIe)

= 500 x (0.8 + (5 x 0.072))

= 500 x 1.16

= 580A (132% full loadcurrent)

5.10.5.4 Check zone

Magnetising current taken by each CT at 72V = 0.072A

Maximum number of circuits = 6

Relay current setting, Ir (I>)= 0.8A

Relay primary operating current,

Iop = 500 x (0.8 + (6 x 0.072))

= 500 x 1.232

= 616A(141% full load current)


Therefore, by setting Ir (I>) = 0.8A, the primary operating current of the busbarprotection meets the requirements stated earlier.

5.10.5.5 Stabilising resistor

The required value of the stabilising resistor is:

RST = VsIr

= 720.8

= 90Ω

Therefore the standard 220Ω variable resistor can be used.

5.10.5.6 Current transformer requirements

To ensure that internal faults are cleared in the shortest possible time the knee pointvoltage of the current transformers should be at least 5 times the stability voltage,Vs.

Vk/Vs= 5

Vk = 360V

5.10.5.7 Metrosil non-linear resistor requirements

If the peak voltage appearing across the relay circuit under maximum internal faultconditions exceeds 3000V peak then a suitable non-linear resistor (Metrosil),externally mounted, should be connected across the relay and stabilising resistor,in order to protect the insulation of the current transformers, relay andinterconnecting leads. In the present case the peak voltage can be estimated bythe formula:

Vp = 2 2VK (Vf VK)

where VK = 360V (In practice this should be the actual current transformerkneepoint voltage, obtained from the current transformer magnetisation curve).

Vr = I'f(RCT + 2RL + RST + Rr)

= 15300 x 1500 x (0.7 + 4 + 90)

= 30.6 x 94.7

= 2898V

Therefore substituting these values for VK and Vf into the main formula, it can beseen that the peak voltage developed by the current transformer is:

Vp = 2 2VK (Vf VK)

= 2 2 x 360 x (2898 360)

= 2704V

This value is below the maximum of 3000V peak and therefore no Metrosils arerequired with the relay. If, on the other hand, the peak voltage VP given by theformula had been greater than 3000V peak, a non-linear resistor (Metrosil) wouldhave to be connected across the relay and the stabilising resistor.The recommended non-linear resistor type would have to be chosen in accordancewith the maximum internal fault current and the voltage setting.


5.10.5.8 Busbar supervision

Whenever possible the supervision primary operating current should not be morethan 25 amps or 10% of the smallest circuit, whichever is the greater.

The Io> earth fault element in the KCGG142 with its low current settings can beused for busbar supervision.

Assuming that 25A is greater than 10% of the smallest circuit current.

Io> = 25/500 = 0.05In

Using the I>>> element for 3 phase busbar supervision

I>>> = 0.08In (minimum setting)

The time delay setting of the to> and t>>> elements, used for busbar supervision,is 3s.

The Io>>/Io>>>/I>> elements not used should be disabled by setting the phaseand earth fault function links PF1, EF1 and EF2 to 0.

5.10.5.9 Advanced application requirements for through fault stability

The previous busbar protection example is used here to demonstrate the use of theadvanced application requirements for through stability.

To ensure through fault stability with a transient offset in the fault current therequired voltage setting is given by:

Vs = 40 + 0.05RST +0.04IF(RCT+ 2RL)

If this value is lower than that given by formula 2 then it should be used instead.

To ensure through fault stability with non offset currents:

(RCT+ 2RL) must not exceed(VK + Vs)/If.

5.10.5.10 Transient stability limit

Vs = 40 + 0.05 RST + 0.04 x 15300/500 (0.7 + 4)

Vs = 45.753 + 0.05 RST

Vs = Ir RST

The relay current setting, Ir = 0.8In

0.8 RST = 45.753 + 0.05 RST

RST = 61Ω

Vs = 0.8 x 61 = 48.8V

Steady state stability limit

(RCT + 2RL) < (VK + Vs)/IF.

Assuming VK = 5 Vs

(0.7 + 4) < (6 x 48.8)

(15300/500)

4.7 < 9.57

Thus, the steady state stability requirement is met.


VK = 5 Vs = 244V

Using the advanced application method the knee point voltage requirement hasbeen reduced to 244V compared to the conventional method where the knee pointvoltage was calculated to be 360V.

Figure 11: Double busbar generating station.

100MVA 15kV

100MVA 132/15kV

Mainreserve

132kV

Figure 12: Phase and earth fault differential protection for generators, motors or reactors.

21 RA

RST22 v

23 RB

RST24 v

25 RC

RST26 v

Protectiverelays

Protectedplant

A

B

C

A

B

C

P1 P2

S1 S2

P1 P2

S1 S2

Figure 13: Restricted earth fault protection for 3 phase, 3 wire system-applicable to starconnected generators or power transformer windings.

A

B

C

P1 P2

S1 S2

27

R RST

28

v

P1

P2

S1

S2


Figure 14: Balanced or restricted earth fault protection for delta winding of a powertransformer with supply system earthed.

A

B

C

P1 P2

S1 S2

27

R RST

28

v

Figure 15: Restricted earth fault protection for 3 phase, 4 wire system-applicable to starconnected generators or power transformer windings with neutral earthed at switchgear.

Figure 16: Restricted earth fault protection for 3 phase, 4 wire system-applicable to starconnected generators or power transformer windings earthed directly at the star point.

A

B

C

P2 P1

S2 S1

27

R RST

28

v

P2 P1

S2 S1

N

A

B

C

P2 P1

S2 S1

27

R RST

28

vP1

P2

S1

S2

P2 P1

S2 S1

N


Figure 17: Phase and earth fault differential protection for an auto-transformer with CTs atthe neutral star point.

Figure 18: Busbar protection – simple single zone phase and earth fault scheme.

Figure 19: Restricted earth fault protection on a power transformer LV winding.

21 RA

RST22 v

23 RB

RST24 v

25 RC

RST26 v

Protectiverelays

A

B

C

A

B

C

P1 P2

S1 S2

P2 P1

S2 S1 P2 P1

S2 S1

21 RA

RST

22v

23 RB

RST

24v

25 RC

RST

26vProtective

relays

ABC

ABC

P2

P1

S2

S1

P2

P1

S2

S1

P1

P2

S1

S2

RN27

28

Buswiresupervision

Contacts frombuswiresupervisionauxiliary relay

A

B

C

RL RL

RCT

RL

RCT

Restrictedearth faultprotection

Data

Protection: RL = 0.04ýRLC = 0.3ý

Transformer: X = 5% RL

11kV415V 1500/5A


5.11 Rectifier protection

Rectifier

Protection

C

A

A

B

RsTransformer

+

ÐB C N

Typical thermal limitfor silicon rectifier

Protection curve

Instantaneousovercurrent

Time

(seco

nds)

Typicalload area

Multiple of rated current

0.11

10

1

2 3 4

100

10000

1000

5 6 7 8

Figure 20: Protection for silicon rectifiers

Figure 21: Matching curve to load and thermal limit of rectifier

The rectifier protection feature has been based upon the inverse time/currentcharacteristic as used in the MCTD 01 and the above diagram shows a typicalapplication.

The protection of a rectifier differs from the more traditional overcurrentapplications in that many rectifiers can withstand relatively long overload periodswithout damage, typically 150% for 2 hours and 300% for 1 min.

The relay I> setting of the relay should be set to the rated rms value of the currentthat flows into the transformer when the rectifier is delivering its rated load.The relay will give a start indication when the current exceeds this setting but this isof no consequence because this function is not used in this application. Curve 9should be selected for the inverse time curve and this cuts-off for currents below1.6 times allowing the rectifier to carry 150% overload for long periods. If this isnot acceptable the I> setting can be adjusted to move the cut-off point relative tothe current scale. The operation time can be modified by adjustment of the timemultiplier setting (TMS) so that it lies between limiting characteristic of the rectifierand the allowable load area.


Typical settings for the TMS are:

Light industrial service TMS = 0.025

Medium duty service TMS = 0.1

Heavy duty traction TMS = 0.8

The high set is typically set at 8 times rated current as this ensures HV ACprotection will discriminate with faults covered by the LV protection. However, ithas been known for the high set to be set to 4, or 5, times where there is moreconfidence in the AC protection.

Use of the thermal element to provide protection between 70% and 160% of ratedcurrent could enhance the protection. It is also common practice to providerestricted earth fault protection for the transformer feeding the rectifier. See theappropriate section dealing with restricted earth fault protection.

5.12 Cold load pick-up

The Cold Load Pick-up (CLP) feature enables the settings of the relay to be changedto cater for temporary overload conditions that may occur during cold starts, suchas switching on large heating loads after a sufficient cooling period, or any loadthat takes a high initial starting current.

Initiation of CLP is usually by an auxiliary contact of the circuit breaker that isclosed when the circuit breaker is in the open state. This would be used to energisea logic input that would be allocated in mask [0A0C Aux3]. If a logic input isalready available to indicate the circuit breaker open status, it can be allocated inmore than one mask; it would not be necessary to use an additional logic input.

For short duration starting loads it may only be necessary to delay the short timeprotection functions. Allocating a relay in output mask [0B12 Aux3] andenergising a logic input via its contacts. The logic input can then be allocated inthe appropriate input masks to block the short time overcurrent elements.

Alternatively setting link LOGB = 1 gives timer tAUX3 a delay on drop-off, when itcan be used to select group 2 settings. Then, with the appropriate preset settingsapplied, the protection levels can be raised above starting currents and held therefor the time set on tAUX3, after which they return to their normal values. To selectthis mode of operation set link [LOG5] = 1 and [SD4]=1. Group 2 settings will bein operation when tAUX3 is energised, that is before the load comes on and forthe set time for tAUX3 after the circuit breaker closes. See also the section entitled“SETTING GROUPS” which explains the alternative methods by which group 2settings can be selected.

This latter arrangement is useful when there are no spare output relays and can beused as an alternative means of blocking the short time elements without usingexternal connections. To achieve it, the elements that are set to a short time must bedeselected in the group 2 settings, or preferably given a higher setting. This ispossible for elements t>>; t>>>; to>> and to>>>.

If delayed initiation is required, allocate the logic input in mask [0A0B Aux2]instead of [0A0C Aux3]; set link [LOG6] =1 and set the required delay on tAUX2.For retrofit installations where an auxiliary circuit breaker contact is not available,undercurrent initiation via tAUX2 may be used. It is possible to set tAUX2 to zero ifno initial delay is necessary.


The above change of setting group can also be enabled if a 52B contact is notavailable, or during instances when the operation of upstream circuit breakers willcut the supply without opening the down-stream circuit breakers. This is achievedby using the loss of load feature associated with tAUX2 and by setting [LOG6] =1.The time delay of the tAUX2 when used in this configuration must be set longerthan the total fault clearance time of the system.

Note: It will be essential to check for correct resetting of any function that isdeselected when switching to group 2 settings.

Figure 22: Compensation for motor starting current

Section 6. DIRECTIONAL OVERCURRENT

Time

CurrentI>>>

Short circuit

Stall

Stall (CLP)

I>t>>>

t>>

I>>

t>

Overload

Overload (CLP)

Zone offorward start

forward operation

Reverse start

¯cÐ90 ¯c+90¯c

I

Is

ÐIs

ÐI

Figure 23: Directional characteristic


Phase fault directional elements are polarised by the quadrature phase/phasevoltage, and the earth/ground fault elements are polarised by the zero sequencevoltage. The directional part of the measurement includes a threshold value on thepolarising quantity, and for phase fault measurement this threshold is fixed.However for earth/ground faults an adjustable threshold is provided to allow asetting above any imbalance in the zero sequence polarising signal to be applied.Control is provided for adjustment of the characteristic angle of the relay.

The directional decision is applied after the current threshold and before thefollowing associated time delay. The directionalisation of any element can beselectively overridden by adjusting software links in the relay menu to a suitablesetting. The undercurrent element I< is the exception since this element is notprovided with directional control.

6.1 Directional overcurrent logic

The logic, shown in Figure 24, provides directional control for stage 1, 2 and 3overcurrent elements in the forward direction and start indication in both theforward and reverse direction. The forward direction will usually be for currentflowing from the busbar to the feeder.

KCEG 142 and KCEU 142 relays only, are supplied with additional links PFE andEFE. They enable the direction of the third overcurrent and earth fault stages to bereversed. There is also the option to select 2/3 logic for all phase trip and startoutputs, by setting link PFF = 1. The 2/3 logic requires more than one phase tooperate before an output is given. These features may not be found in the very firstmodels manufactured.

6.2 Directional start output

When the current threshold I> is exceeded and the polarising signal is above thethreshold Vp>, an output is directed to the [0B06 I> Fwd] mask for forward currentflow and to the [0B07 I> Rev] for reverse current flow. A non-directional start canbe obtained by allocating the same output relay in both start masks so that itoperates for forward or reverse current flow.

If all three elements are selected to be non directional (links PF3, PF4 and PF5 setto ‘0’) then the forward start will become a non-directional start, but the reversestart will retain its directionality (on the series 1 relays, KCEG110/130/140/150,the reverse start was inhibited when all three elements were selected to be nondirectional).

6.3 Directional first stage overcurrent

If link PF3=0 the time delay t> will start timing when the current exceeds the I>setting to give a non-directional trip via the appropriate relay mask [0B08 tA>],[0B09 tB>], or [0B0A tc>]. With link PF3 set to “1” the time delay will only run ifthe current exceeds the I> threshold and is in the forward direction. Externalcontrol is asserted via input mask [0A04 Blk t>] and when this input is energisedthe time delay is reset to zero after the reset delay (tRESET).


6.4 Directional second and third overcurrent stages

Elements I>>/t>> and I>>>/t>>> can also be selectively directional, or non-directional. To directionalise them links PF4 and PF5 respectively, should be set to‘1’. If these links are set to ‘0’ then the elements will be non-directional. The delayhas a definite time characteristic for these elements, which can be blocked via theappropriate input mask [0A05 Blk I>>] and [0A06 Blk I>>>]. There are no startfunctions associated with these two elements.

6.5 Directional earth fault logic

The logic for the earth fault element is similar to that described for phase faults.An independent set of software links, input masks and relay masks are provided togive optimum flexibility to the user.

6.6 Application of directional phase fault relays

It is normal practice to set the characteristic angle of the relay (φc) to the anglebetween the prospective fault current and the polarising voltage. A fault will thenlie at the centre of the directional characteristic. For a three phase fault the faultcurrent will normally lag the phase voltage by an angle of 45° to 60°. Howeverthe polarising voltage is the quadrature line voltage, which lags the phase voltageby 90°. Thus if the fault current lags the phase voltage by an angle (–φ), the angledifference with respect to the polarising voltage will be (90° – φ).Thus characteristic angle setting for the relay will be the phase angle of the faultcurrent with respect to the polarising voltage. Thus φc = (90° – φ) and so for a faultangle of –60° the setting for φc will be +30°.

K Range series 2 relays have the range for the characteristic angle settingincreased to ±180°, so that it is possible to reverse the direction of operation.For the above example the characteristic angle setting is +30° for operation whencurrent flows from the busbar to the feeder, so for operation when current flowsfrom the feeder to the busbar the characteristic angle must be shifted by 180°.Thus for operation in the reverse direction φc = –(90 + φ) = –150°.

The minimum operating value of the voltage input to the directional overcurrentrelay should be as low as practicable from the aspect of correct directionalresponse of the relay itself. This follows because of the important requirement forthe relay to achieve correct directional response during a short circuit fault close tothe relay when the voltage input can be below 1% of rated value. Furthermore,there is no restriction on the minimum operating value from the aspect of the powersystem or voltage transformer performance. Hence the threshold for the phase faultelements of the KCEG relays has been set at 0.006Vn.

6.7 Synchronous polarisation

The phase directional elements are polarised by the quadrature line voltage,referred to a cross polarisation, they will always have a polarising signal for close-up phase to phase faults. However, for close-up three phase faults the polarisingvoltage may be lost completely and synchronous polarising is then used.

The phase angle of the line voltages with respect to the sampling frequency ismeasured for each cycle and the last value measured is stored in memory.When the polarising signal is lost the last stored phase reference for the voltage isused for the directional decision. The phase angle of the current relative to thesampling frequency is measured and from this is subtracted the stored phase angleof the polarising voltage to give the phase angle of the current with respect to the


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polarising voltage and this is compared with the set operational angle limits foroperation. Because the relay tracks the frequency the stored phase reference forthe voltage holds good even though the frequency may drift during the fault andhence the term synchronous polarisation.

The duration of the synchronous polarisation is 320ms, but an option is nowprovided to extend this to 3.2s to allow operation of the IDMT element.The duration is selected with link [PFB]. For PFB=0 duration is 320ms and forPFB=1 duration it is increased to 3.2s. The longer duration will be useful whenfault current is limited and the operation time of the relay is expected to berelatively slow for close-up faults.

6.8 Application of directional earth fault relays

The earth fault elements use the residual voltage as the polarising quantity.With the KCEG 142/242 relays this voltage is internally derived from the threephase/neutral voltages applied to the relay. With the KCEG 112/152 this voltagehas to be externally derived from an open delta winding on the line voltagetransformers, or via star/open delta interposing voltage transformers.

Note that the KCEU 142/242 relays measure residual voltage by means of aninternal resistor network and VT. However, the external VT connections to the relayare the same as those for the KCEG 142/242 relays, namely three phase and oneneutral connection. This is therefore applicable where a suitable star connected VTwinding is available. However, for applications where there is only a broken deltawinding available to polarise the relay, this is accommodated by connecting therelay as shown in Figures 21 and 22, Appendix 3. From this figure it can be seenthat the residual voltage must be applied between one phase voltage input andneutral, ensuring that the remaining two phase voltage inputs are tied down toneutral. It is important that these two connections are not left floating, as anincorrect residual voltage measurement would result.

The characteristic angle will be directly as marked for earth faults and laggingangles of between 0° to –60° may be used as appropriate, dependent on thesystem earthing arrangements.

When providing sensitive earth fault protection for an insulated system a corebalance transformer is recommended. Where this is oriented as for an earthedsystem ie. with the relay looking down the feeder, the relay characteristic angleshould be set to +90°. If the current transformer is reversed, anticipating capacitivecurrent flow from the feeder onto the busbar, –90° should be used.In such applications, relatively sensitive current settings will be required for thedirectional earth fault relay. The standard setting range of the earth fault elementsin the KCEG relay models goes down to 0.5% of rated current. If settings moresensitive than this are required, the KCEG 112 and KCEG 152 models can besupplied with a setting range matching that of the KCEU models, namely, down to0.1% of In. For complete details on available setting ranges, refer to TechnicalData section Chapter 7.

More detailed information regarding application of the KCEG 112/152 relays toinsulated systems, is available in a separate application guide, reference R6554.

Where a directional relay is used to prevent sympathetic tripping of the earth faultovercurrent element, which would otherwise result from the currents flowing via thecable capacitance to earth, an angle setting of +45°(lead) is recommended.


For earth faults the minimum operating value of the residual voltage input to thedirectional earth fault relay is determined by power system imbalance and voltagetransformer errors. The zero sequence voltage on a healthy distribution system canbe as high as 1.0%, also the voltage transformer error can be 1.0% per phasewhich results in a possible spurious residual voltage as high as 2.0% under healthyconditions. In order to take account of both of the foregoing quantities and thuseliminate unwanted relay operation it is necessary to introduce a minimumoperating value of up to 3.5%. In practice, a choice of settings of say 2.0% to4.0% should be considered, with perhaps 10% and 20% for high resistance andinsulated neutral systems respectively. The setting for Vop> will be found in theEARTH FAULT setting column of the menu and should be set appropriately, takingthe above notes into account.

Note: The KCEG 140 required a residual voltage in excess of 6%Vn before thevoltage threshold circuit would function, regardless of the Vop> setting.With the KCEG 142/242 the sensitivity of this circuit has been improved toless than 0.6%Vn.

For protection of arc suppression (Petersen) coil earthed systems, a sensitive currentsetting is required to enable accurate detection of the relatively small currentsflowing under fault conditions. Angles in the region of +5°(lead), 0°, –5°(lag) arecommon, with the relays having suitably fine setting adjustment of 1°.

6.9 Power directional earth fault element

An alternative option for arc suppression (Petersen) coil earthed systems isprovided by the KCEU 142/242 relays. These relays operate when the powermeasured in the residual circuit exceeds the power setting (Po>). Power ismeasured in watts and is equal to VIcosφ.

Thus for operation the residual current must exceed Po> before it can operate.Vo cosφ

The residual current required to operate the relay is high when there is littleresidual voltage. By virtue of this feature the relay effectively ignores any residualspill current, resulting from mismatch of the line CTs, due to the fact that there isnegligible zero sequence voltage present under load conditions.

The power characteristic is relative to the set characteristic angle (fc), which willtypically be set to 0°. To reverse the direction of operation the characteristic angleis changed by ±180°.

Note: If the power setting Po> = 0, then the normal directional characteristic willbe operative instead of the power characteristic.

More detailed information regarding the application of the KCEU 142,242 relaysto Petersen Coil Earthed systems, is available in a separate application guide,reference R6554.

6.10 Directional stability for instantaneous elements

Directional relays are required to withstand a fault in the reverse direction withoutoperating. In addition they are required to remain stable (ie. not operate) when thereverse fault current is removed and the current falls to zero, or to a level that isbelow the current setting of the relay and in a forward direction. With timedelayed protection, directional stability is not usually a problem, but withdirectionalised instantaneous overcurrent relays it is much more difficult to achieveand momentary operation may occur when the fault is removed.


The software of the K Range relays has been arranged to reduce transientoperation to a minimum, but even so it is advisable to set the associated time delayfor any directional overcurrent element to between 40ms and 200ms, dependingon the system X/R ratio and the maximum fault level, to ensure stability under thiscondition.

For a two phase to earth fault, close to the operating boundary, one definite timephase element may give a directional decision that is different to the other two andcould be considered to be incorrect. To eliminate the protection performing in away that is not expected a better decision can be made by setting link PFF = 1 toactivate the 2/3 logic on both the trip and start outputs. Earth fault protection willthen be essential to clear single phase faults. This was not a problem withdirectionalised IDMT protection because of its inherent current/time characteristic.

6.11 Protection of circuits with multiple in-feeds

For the blocked overcurrent protection to be applied to a feeder that can be fedfrom either end, or a busbar with multiple in-feeds, a directional feature mustincorporated. The START elements of any relay that detects current flowing from theprotected zone must block the operation of any relays that detect current flowinginto the protected zone. The directional feature is used to establish if the current isflowing into, or out of, the protected zone. The principle can be applied to theprotection of busbars, parallel feeders, as shown in the following example, and itis also suited to ring circuits to simplify grading problems.

The following diagram shows a busbar with several feeders connected to it anddivided by a bus section circuit breaker. The dotted lines indicate the zones ofprotection that can be formed using short time overcurrent protection arranged in ablocked overcurrent scheme. The basic IDMT protection is still applied in thetraditional fashion, but is now augmented by the additional overcurrent elementswithin the feeder protection arranged to provide unit protection for both theirassociated feeder the bus section to which the feeder is connected.

KCEG

KCEGKCEG KCEG

KCEG KCEGKCEG

Incomer

Feeder 4

Incomer

Feeder 1 Feeder 3

142 142 142

142142142

Feeder 2

142

Figure 25: Circuit with multiple infeeds


6.11.1 Blocked directional overcurrent protection

Because the busbar is divided by a circuit breaker an extra directional overcurrentrelay is required to divide the protection into a separate zone for the bus sections.The standard connections used for the relays connected to each feeder is such thatthe forward start relays operate for fault current flowing from the busbar to thefeeder and the reverse start for fault current flowing towards the busbar. For thebus section relay the forward start operates for current flowing from the left handto the right hand bus section.

6.11.2 Blocked overcurrent protection for the feeder

The KCEG 142 relays will usually be arranged to protect the feeder and theforward direction will then be for current flow from the busbar to the feeder.The current threshold for the I>>/Io>> element would be set above any transientloads. They can be prevented from overreaching the ends of the feeder andoperating for faults beyond the busbars, by applying the blocked directionalovercurrent principle. This forms a unit protection scheme for the feeder and canbe useful when the normal time grading steps are not possible.

Set links PF4 = 1 and EF4 = 1 for these elements to be directionalised, so that theywill not operate for faults on the busbar behind them. Then to prevent themoverreaching the remote busbar the reverse start contact of the relay at the otherend of the line is arranged to block the t>>/to>> time delays via a logic input.

For a fault on the feeder, current will only be seen to flow in the forward direction,into the feeder, and so the protection will operate. This arrangement is also tolerantto high transient loads, so allowing the short time elements to be set closer to theload current.

6.11.3 Blocked overcurrent protection for the bus section

The circuits connected to the left hand bus section in Figure 25 are the incomer,feeders 1 & 2 and the bus section. The I>>>/Io>>> elements of each relay maybe used to form the blocked directional overcurrent protection for this application.The I>>>/Io>>> elements shall be directionalised by setting function links PF5 = 1and EF5 = 1. The forward direction for these relays will be for current flowing fromthe bus zone to a feeder, so it will be necessary to reverse the direction ofoperation for the third stage by setting links PFE = 1 and EFE = 1.

The forward start contacts from each relay are used to define the boundary of thebus zone. To do this, the forward start contacts of each relay connected to a zoneare connected in parallel across a pair of buswires and arranged to block theoperation of both the t>>>/to>>> time delays of each relay when current flowsfrom the busbar by any legitimate path. Thus if fault current flows away from thebusbar the overcurrent protection is blocked and if current flows towards thebusbar and does not flow away down any other legitimate circuit the busbarovercurrent protection operates to clear the fault.

Previous notes on this application referred to the use of a non directional elementto cover the bus zone. However, based on experience we now recommend the useof directional elements for improved stability. Stability can be further improved byapplying 2/3 logic to all phase fault start and trip outputs. However, operation ofthe earth fault element will then be essential to cover single phase faults and forsolidly earthed systems the zero sequence voltage should be calculated to ensurethat there is sufficient to operate the relay at the minimum fault current.


Application of Midos K Range relays for single and double busbar protection isfurther described in publications R4112 and R4114.

Note: The response of directional overcurrent relays to power system disturbanceswill vary with the earthing arrangements. It is not practical to consider allconfigurations of the power system and so the application notes in thisdocument can only be a general guide. Each application will need to beengineered to suit the system.

Section 7. THERMAL OVERCURRENT

The thermal overload protection shares the time constant setting with the thermalammeters and thus a compromise will be necessary if they are to be used at thesame time. It is recommended that the time constant is chosen to suit the protectionin such instances. The settings for the time constant (TC), the continuous thermalcurrent rating (Ith>) and the thermal alarm (th>) will be found in the menu columnscontaining the phase fault settings.

The time constant can be set between 1 minute and 120 minutes in 1 minute stepsand the thermal current setting (Ith>) can be adjusted between 0.08In and 3.2In.The thermal protection responds to I2 and will operate faster as the currentincreases, but for currents in access of 5.3 times rated current the operation timewill remain the same as that for 5.3 times rated current. This will not be a problemin practice because the normal IDMT, or definite time, protection will normallyhave taken over at a lower level of current.

7 6 5 4 3 2 1 0

01

PF0

RESET Ith0A11Thermal

reset

Trip

Alarm7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

th ALARM

th TRIP

0B17

0B18≥1

≥1

Figure 26: Thermal alarm and trip logic

7.1 Thermal state

In simplified terms the thermal state is a percentage thermal current limit that hasbeen attained by the thermal replica. The thermal state will be found underMEASURE 3 in cell 0407 and can be displayed on the front of the relay byviewing this cell or selecting it from the default display.

The thermal state = I2[1-e-t/T]/[Ith>]2 x 100 = %Ith>

Final value of thermal state = [highest thermal ammeter reading]2 x100%[continuous thermal current limit]2

The thermal state will tend to 100% when the highest of the three thermal ammetersis displaying a current equal to the set thermal current limit (Ith>).

The time to reach 100% will depend upon:

Applied current

Prefault load current

Thermal time constant

Continuous thermal rating


7.2 Thermal trip and alarm levels

A thermal trip will be given via the output mask [0B18 th Trip] when the thermalstate reaches 110%. This is equivalent to the current being in excess of 1.05Ith>.It should be noted that the thermal trip will remain asserted until the replica coolsand the thermal state falls below the trip level.

In addition an alarm setting can be set for a thermal state between 0% and 110%.When this threshold is exceeded an output can be obtained via the alarm outputmask [0B17 th Alarm].

7.3 Operation time

The operation time characteristic is given by he following expression:

t = T.LOGe Ix2 Ð PIx2 Ð 1.10

where

t = time in minutesT = selected time contstantIx = current in multiples (Ith>)P = (per unit of prefault load)2P = (IL/Ith>)2

The characteristic curves will be found in the appendix to this document where thetimes are shown as a multiple of the selected time constant for various levels ofprefault load.

7.4 Thermal memory

When the auxiliary energising supply is lost the thermal state is stored in nonvolatile memory. On restoration of the supply the thermal state is restored.However, if the stored value of the thermal state is in excess of 90%, the restoredthermal state will be set to 90%.

7.5 Thermal reset

The thermal state can be reset to zero after the password has been entered byperforming a reset function on cell [0407 Thermal] under MEASURE 3. This can beachieved via the user interface of the relayby pressing the reset key [0] for onesecond whilst this cell is displayed, or by a 'reset cell' command via the serial port.However, this cell is protected and the password must be entered before it can bereset.

Alternatively, the thermal state can be reset by energising a logic input that hasbeen allocated in the input mask [0A11 RESET th]. All input masks are passwordprotected against change, but once a logic input has been assigned to this functionit is not necessary to enter the password again before the reset function canrespond to this input being energised.

Note: The thermal state cannot be reset whilst viewing cell 0407 from the defaultdisplay.

If the thermal state is greater than 90% it will be reset to 90% after a breakin the auxiliary supply.

If link PF0 = 0 in either setting group, then the thermal state will not reset tozero when that group is selected. If the thermal protection is not to be used


the thermal state should be manually reset to zero to clear the memorisedstate.

7.6 Dual time constant characteristics

It is possible to set different time constants in setting group 1 and 2 and soproduce dual characteristics with dual time constants in a similar way to thecomposite curves described in Section 4.8. For such an application the settinggroup will be arranged to change in response to the current exceeding one of thecurrent thresholds I>> or I>>>.

7.7 Application of thermal protection

The thermal protection characteristic can be used to protect electrical equipment insuch a way that the full thermal capacity is utilised with due regard to the thermalinertia, but in a manner that prevents unacceptable temperatures from beingattained. It can be applied to standard high voltage cables with natural coolingand to dry type power transformers.

The setting (Ith>) should be set to the maximum continuously rated current for theprotected item of plant. If the current transformer (CT) ratio has been entered thenthis will be in primary quantities, but if the CT ratio has been set to 1:1 then thecontinuous rated current entered should be that referred to the secondary windingof the CT.

The appropriate thermal time constant (T) must be entered and the following tablegives some suggested values for typical cables. The curves for the thermalcharacteristic are to be found in the appendix to this document and it will be seenthat they take due account of the pre-load current.

The typical values of time constants in the following table are paper insulated leadsheathed cables, or polyethylene insulated cables laid above ground or inconduits.

ConductorRated voltage of cable

cross 6 to 11kV 22kV 33kV 66kVsection (mm)2 T minutes T minutes T minutes T minutes

25 10 15 – –35 10 15 – –50 10 15-25 40 –70 15 25 40 –95 15 25 40 60120 20 25 40 60150 25 40 50 60185 25 40 60 60240 40 40 60 75300 40 60 60 90

Typical time constant values for cables


Other protectable items T minutes

Dry-type transformers 40Air-cored reactors 40Capacitor banks 10Overhead lines from 100mm2 Cu or 150mm2 Al 10Busbars 60

Typical time constants for other protected plant items


Section 8. UNDERCURRENT

These elements provide a quick response to an undercurrent condition when theyare used to terminate the breaker fail timer sequence and close the fault recordsetc. To achieve this the peak value of each both half cycles of current arecompared with the current setting threshold I<. An undercurrent indication isindicated given when the peak value of either the positive, or negative, half cycleis below the I< threshold giving a theoretical detection time of half a cycle.A logical OR function is performed on the outputs of the three phase faultundercurrent elements to produce an output when an undercurrent condition isdetected in all three phases. Similarly the peak value of the residual current iscompared with the earth fault undercurrent threshold Io< to produce a separateoutput.

The undercurrent elements are also be used to provide some additional functions inconjunction with the auxiliary timers, but it should be remembered that they areresponsive to peak measurement and will be more responsive to the harmoniccontent of the waveform.

8.1 Breaker failure protection

Figure 27: Circuit breaker fail logic

The breaker fail timer (tBF) will start to time if relay RLY3 operates and at least oneof the undercurrent elements is detecting current flowing in the circuit. The breakerfail timer can also be initiated in response to a logic input being energised if thatlogic input is allocated in the input mask [0A09 EXT TRIP]. If tBF times out beforethe undercurrent element, relay RLY3, and the external trip reset, then the outputmask [0B0F BF] will be energised and any output relay assigned in this mask willpick-up. If this relay picks-up the circuit breaker is assumed to have failed to clearthe fault and this output relay can be then used to back trip the next circuit breaker,nearer the source, to clear the fault.

If a blocked overcurrent scheme is in use, logic link LOG2 can be set to ‘1’.This will cause the start relays to reset releasing the block on the upsteram relay toallow it to trip directly and clear the fault.

The time delay (tBF) will typically have a setting in the range of 200 to 400ms.The exact time will depend on the sum of the delays in the tripping path includingthe operation time of the circuit breaker.

Reset start relays

7 6 5 4 3 2 1 0

RLY3

EXT. TRIP0A09tBFI<

Io<

LOG210

7 6 5 4 3 2 1 0CB FAIL0B0F

≥1


Section 9. UNDERVOLTAGE

The undervoltage elements can be selected to respond to changes in line voltageby setting link PFA=0, or to the phase voltage by setting link PFA=1. The followingtime delay tV< can be selected to time when ALL three phase elements indicate anundervoltage condition by setting link PF9=0. Alternatively the delay can beselected to start in response to any one, or more, elements indicating anundervoltage condition by setting link PF9=1. One, or more, output relays can beassigned in mask [0B13 tV<] to pick-up when the undervoltage condition has beenpresent for longer than the set time tV<.

Figure 28: Undervoltage logic

The undervoltage function can be selectively blocked when the circuit breaker isopen if link PF8=1. A logic input should be energised via an auxiliary contact ofthe circuit breaker that will be closed when the circuit breaker is closed. This logicinput will indicate when the circuit breaker is closed and must then be assigned inthe input mask [0A0E CB CLOSED]. If the undervoltage element is to beoperational when the circuit breaker is open then set link PF8=0, then assigning alogic input in mask [0A0E CB CLOSED] is not essential to the operation of theundervoltage function.

9.1 Undervoltage trip

An undervoltage trip is often used to isolate the supplies to machinary when thesource of electrical supply is lost. This is a safety feature that prevents equipmentstarting-up unexpectedly when the supplies are eventually restored.

The undervoltage elements can arranged to trip the circuit breaker when all threephase voltages have been lost and for this application it does not matter if thephase, or the line, voltages are used. It is advisable to block the undervoltage tripfunction when the circuit breaker is open, otherwise the trip command will bemaintained and reclosing of the circuit breaker may be prevented.

Set links as follows: PF8 = 1; PF9 = 0, or 1; PFA = 0.

An appropriate delay may be applied to tV< to prevent tripping on voltage dips.

Assign relay RLY3 in output mask [0B17 tV<].

Assign a logic input, to indicate CB closed, in input mask [0A0E CB CLOSED].

These settings will be applicable to trigger the disturbance recorder for anundervoltage condition, but it would be advisable to assign an alternative relay toRLY3, because this relay is assigned functions that cause the fault flags to belatched.

7 6 5 4 3 2 1 0CB CLOSED IND

1V<PF8

0

0A0E

&10

PF9 tV< 7 6 5 4 3 2 1 0tV<0B13

≥1


9.2 Voltage controlled overcurrent protection

Applications where the fault current may be less than the nominal full load,eg. generation current decrement, or remote back-up protection of long feeders,will benefit from the application of voltage controlled overcurrent protection.Discrimination between low load current and a low fault current is achieved bydetecting the reduction in the line voltage, at the relaying point, that is presentduring a fault and not during normal load conditions. For this application thefollowing settings should be applied to the relay:

Set links as follows: PF8 = 1; PF9 = 1, or 1; PFA = 0 (the line voltage is used toprevent operation during earth fault).

Assign a logic input, to indicate CB closed, in input mask [0A0E CB CLOSED].

Assign any relay, but not RLY3, in output mask [0B17 tV<] and externally wire thiscontact to energise an unused logic input and then assign this input in mask [0A0DSEL GRP2]. This will select the group 2 settings when an undervoltage conditionoccurs.

Apply normal settings for phase faults in group 1and the appropriate lower phasefault settings in group 2.

Section 10. UNDER FREQUENCY

The under frequency threshold (F<) is used in conjunction with an auxiliary timer toprovide a load shedding function. Setting link PFD = 1 will enable the underfrequency element to initiate tAUX1 when the frequency falls below the setting F<provided a logic input is assigned in the input mask [0A0A AUX1] is energised, togive a time delayed output via any relay assigned in the output mask [0B10AUX1]. This will usually be relay RLY3, the main trip relay. This feature enables theload shedding to be graded by both frequency and time.

The frequency measurement will default to the set rated frequency when the signalsare too small to measure and provided the under frequency setting is lower thanthis no output should occur. However, it is known that when a circuit breaker isopened there may be small signals present due to mutual coupling, or ringingeffects, that generate signals to which the underfrequency element can respond.In such cases the underfrequency can be gated with some other function such as alowset overcurrent element, or the circuit breaker closed indication via the inputmask [0A0A AUX1].

Section 11. AUXILIARY TIMERS

When the auxiliary timers tAUX1, tAUX2, and tAUX3 are not being used by theinternal logic of the relay they may be used as discrete time delay elements.Timers tAUX1 and tAUX2 will start to time when a logic input assigned in theirinput masks is energised. They will then energise an output relay assigned in theirassociated output masks after the set time has elapsed. Time delays can be setfrom 0.01s up to 24 days.

Timer tAUX2 may be used as a discrete time delay function, or to give delayedinitiation of tAUX3. It can also be used to give longer reset delays for thedisturbance recorder (see the section on Disturbance Recorder).


Timer tAUX3 is slightly different to tAUX1 and tAUX2 in it can be selected to give adelay on pick-up as in series 1 relays, or alternatively a delay on drop-off.Software link LOGB is used to make the selection. Set LOGB = 0 for delay on pick-up and LOGB = 1 for delay on drop-off.

Figure 19: Auxiliary timer logic

The cold load start timer has been deleted in the K Range series 2 relays and whenthis function is required tAUX3 should be utilised with link LOGB = 1. For delayedinitiation of the cold load start, set link LOG6 = 1 when the delayed initiation willbe given by tAUX2.

11.1 Extra earth fault stage

Setting link LOG4=1 will enable the earth fault undercurrent element Io< to starttAUX2 when the current exceeds the Io< setting. This gives a fourth earth faultstage, but note that this element is responsive to peak measurement and will notprovide a high degree of rejection to harmonic currents.

11.2 Loss of load protection

Setting link LOG3=1 will enable the phase fault undercurrent elements to starttAUX2 when the current is less than the I< setting. This can be used to start thecold load start sequence in retrofit installations. It can also be used to indicate lossof critical loads.

11.3 Delayed under frequency trip

Setting link PFD=1 will enable the under frequency element to initiate tAUX1 whenthe frequency falls below the setting F<, to give a time delayed output via anyrelay assigned in the output mask for tAUX1. This can be used to provide a timedelayed under frequency trip for load shedding. This feature enables the loadshedding to be graded by frequency and time setting.

The under frequency will not maloperate when the signal that is being frequencytracked is too small to track. This is because the frequency tracking will default tothe set rated frequency and provided the under frequency setting is lower than thisno output will occur.

Recorderstopped

7 6 5 4 3 2 1 0 tAUX1

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

AUX30A0C

LOG3

Io<

I<10

10

LOG4

F<

10

I<

SD8

AUX20A0B3SEC

tAUX2

tAUX3

&

LOG6

SD501

SD80

SD60

1 1

01

AUX10A0A7 6 5 4 3 2 1 0

AUX30B127 6 5 4 3 2 1 0

AUX2

Reset trip flags

Resetdisturbance

recorder

7 6 5 4 3 2 1 00B11

AUX10B10

Recorderstopped

01

LOGB

10

PFD=1

≥1

≥1

≥1


Section 12. SETTING GROUP SELECTION

The relay has two setting groups, but as supplied only setting group 1 will bevisible. To make the second group of settings visible in the menu, set function linkSD4=1 in the SYSTEM DATA column. The value of the group 2 settings isunimportant when link SD4 = 0, because group 1 settings will be in use by default.The menu cell 000E, in the SYSTEM DATA column, is a read only cell that displaysthe setting group that is in operation.

Note: The logic associated with the change of setting group has changed fromthat in the original K Range relay and the following notes only apply toK Range series 2 relays.

Figure 30: Setting group selection logic

12.1 Remote change of setting group

Link [SD3] must be set to “1” before the relay will respond to a remote commandto change the selected setting group. Because the command cannot be sustainedover the serial link a set/reset register is used to remember the remotely selectedsetting group. When link SD3=1, the set/reset register shall change to 0/1 inresponse to the respective commands <Set Group 1>/<Set Group 2> via the serialport. When the value of set/reset register is “0” then the group 1 settings shall bein operation and when its value is “1” the group 2 settings will be in operation.The state of this register stored when the relay is powered down and restored onpower up.

When link SD3=0 the value of the set/reset register will no longer change inresponse to remote command and will retain its last set state prior to settingSD3=0. When link SD3=0 the value of the cell cannot be changed via the serialport and the value of this register will have no effect on the setting group in use.

Note: If [SD4] = 0 then the group 2 settings will be hidden and group 1 will beactive by default.

12.2 Manual change of setting group

Link [SD4] must be set to “1” to make the second setting group active.Then manual selection of Setting Group 2 shall be effected by setting link LOG8=1in the LOGIC column of the menu.

12.3 Controlled change of setting group

Link SD4 must be set to “1” to make the second setting group active. Now aninternally generated control signal from timer tAUX3 via link LOG5 will selectsetting group 2. Alternatively, energising a logic input allocated in mask [0A0DSTG GRP2] will select setting group 2. Note that tAUX3 will have a delay on pick-

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

1

SD30

LOG8

10

AUX3

STG GRP 2

0A0C

0A0D

RESETRemote reset Grp1 0SET

Remote set Grp2

LOG6

1

LOG5

10

SD4

10

1 AUX37 6 5 4 3 2 1 0

Change to setting group2

0B12tAUX3 1

0

LOGB

≥1

≥1


up if link LOGB = 0 and delay on drop-off if LOGB = 1. The logic input could beenergised via the contacts of one of the output relays so that change of settinggroup will be in response to some protection function such as an overcurrentelement operating, or the directional contacts changing state. Three example usesare given below:

Dual rate inverse time curves [see Section 4.8]

Cold load pick-up [see Section 5.12]

Dual thermal time constant [see Section 7.6]

Voltage controlled overcurrent [see Section 9.2]

Section 13. DUAL POWERED RELAYS

Dual powered relays are powered from an AC, or DC, auxiliary supply.This supply need not be secure because the relay will draw current from the currenttransformer circuit in the absence of the auxiliary supply.

13.1 Powered from current transformers alone

When powered from the current transformer circuit alone, the minimum current tooperate the relay is that required to establish the power supply rails within therelay. Lowering the design value of this parameter increases the burden on thecurrent transformers and the power dissipated within the relay case. The limits aretherefore a compromise based on these factors:

Minimum current to power the relay for phase faults = 0.4In

Minimum current to power the relay for earth faults = 0.2In

However, a combined three phase and earth/ground fault relay will operate withlower earth/ground fault current settings when the load current in the protectedcircuit is sufficient to power the relay ie. greater than 0.4In. Settings less than0.2In are provided for earth faults, but they must be used with discretion.

Figure 31: Start-up time delay

Multiple of minimum current to power the relay

Time

(seco

nds)

0

0.2

1 7 10

0.4

0.6

0.8

70 100


When switching onto a fault, the relay will be delayed in operation by the start uptime and this delay will need to be taken into account in any grading exercise.The delay is the time taken by the processor to initialise its registers, read insettings from non-volatile memory and perform self checks. There will be anadditional delay whilst the power supply builds up, but this will be less significantwhen using an inverse time/current characteristic as the power supply delaysimilarly varies with current. The start-up time is not reduced by lowering the timemultiplier setting. With prefault load current there will be no start-up time and therelays will operate within their normal time settings.

Note: Where the start-up delay cannot be tolerated it is recommended that therelay is also powered from an auxiliary AC voltage supply so that it can beup and running before a fault occurs. It will also make stored disturbanceand event records more secure, because they are discarded when the relaypowers down.

13.2 Powered from an auxiliary AC voltage and from currenttransformers

The addition of an auxiliary AC, or DC, voltage supply to power the relay will:

– enable the settings to be changed when the protected circuit is de-energised.

– enable records to be retrieved and control functions to be carried out over thecommunication link.

– reduce the burden on the line CTs.

When using an auxiliary AC voltage, it may be lost during a fault, when powerwill be drawn from the current transformer circuit to maintain the relay in a fullyoperational state. However, if the source of the auxiliary voltage is carefullychosen it is unlikely to be lost completely during earth faults but it may collapse to50% of its rated value. Provided the voltage is still above the minimum required topower the relay, very low earth fault settings can be successfully applied. In theabsence of the auxiliary voltage the relay is not guaranteed to operate for earthfault currents less than 0.2In.

No alarm is given for loss of the ac auxiliary voltage, unless it is externallymonitored by a separate supervision relay.

13.3 Special application notes for dual powered relays

Dual powered relays may be fitted with eight opto-isolated inputs and eight relayoutputs, but at the claimed minimum operating current they cannot all be energisedat the same time. If they are, then the minimum operation current will be increased.However, in applications requiring a dual powered relay it is unlikely that morethan two output relays will be energised at any one time. The following tableshows how the minimum operating current varies with the number of relays (notincluding the watchdog) and inputs that are to be energised at the same time.

No.of output relays energised 2 4 6 88 opto-inputs energised 1.3xImin 1.5xImin 1.7xImin 2.0xImin6 opto-inputs energised 1.3xImin 1.4xImin 1.6xImin 1.8xImin4 opto-inputs energised 1.2xImin 1.3xImin 1.5xImin 1.8xImin2 opto-inputs energised 1.1xImin 1.2xImin 1.4xImin 1.6xImin

Imin = 0.4In for phase faults and 0.2In for earth/ground faults.


13.4 Dead substation protection

The dual powered relays derive power for the electronics and the trip coil of thecircuit breaker from the line current transformers and optionally from an auxiliaryvoltage supply. Applying one of these relays on the incoming feeder to thesubstation will ensure that the substation is still protected in the event of completefailure of the auxiliary supplies.

The application limitations are that the setting range of these relays is a little morerestricted when power is being derived from the current transformers alone andthat the circuit breaker must have a suitable trip coil fitted. The tripping energy isprovided by a 680µF capacitor charged to 50V and the circuit breaker shouldreliably trip when this capacitor is discharged into its trip coil.

13.5 Capacitor discharge tripping

Dual powered relays may use either of the above methods. In addition, theseparticular relays charge an internal capacitor from the current circuit and also fromthe auxiliary voltage circuit (Figure 32). This capacitor is 680µF and it is chargedto 50V dc. It may be discharged directly into a suitably sensitive trip coil via oneof the programmable output relays. The minimum energy fed to the trip coil is thatfrom the capacitor, but in most cases it will be supplemented by a current from theauxiliary voltage circuit and/or the current circuit.

When energized from current alone the lowest current for which the relay willoperate will be that necessary to start up the power supply. To be able to uselower fault settings an auxiliary supply will be required.

The capacitance discharge circuit is not isolated from the auxiliary supply and toprevent the relay from being damaged, no external ground connection should bemade to this circuit.

Figure 32: Capacitor discharge trip

13.6 AC series tripping

As an alternative the trip capacitor in the dual powered relays may be dischargedinto an auxiliary relay. This relay will be de-energized in the quiescent state, withits break contacts short circuiting the trip coils of the circuit breaker (Figure 33).

The trip coils are connected in series with the current transformer secondary circuitso that, when the auxiliary relay is operated, the full secondary current is divertedthrough the trip coils.

To cover all fault conditions, three trip coils are required and may be necessary tolimit the maximum energy that can be fed to each coil, by means of saturatingshunt reactors.

9

10

+

RLY3

Relay

44

42

Trip


Figure 33: AC series trip arrangement

Section 14. AUTORECLOSE - single shot scheme

In many feeder protection schemes, autoreclose is used as an effective tool torestore supply following transient faults such as flash overs caused by lightningstrikes.

Areas prone to sever lightning activity usually require multi-shot autorecloseschemes to deal with multiple strikes. These schemes are quite complex, ofteninvolving enabling and disabling of certain protection functions at each stage andhence requires complex scheme logic and timing routines as provided in the KAVRand KVTR relays. However, there are many instances where transient faults arerare and not justifying dedicated autoreclose schemes, but even so a simple singleshot autoreclose scheme can reduce the number of instances of lost supply due tothese occasional transient faults.

14.1 Overview

The scheme provides a single shot autoreclose function using the scheme logiccapablilities of the KCGG or KCEG overcurrent relays together with a singleexternal auxiliary relay.

The auxiliary relay is an MVAA 15 relay or similar electrically reset relay, which isutilised to latch the autoreclose initiate signal. This has the added advantage ofpreventing hunting of the scheme.

The autoreclose dead time and reclaim time are controlled by the two auxiliarytimers tAUX2 and tAUX3 that form an integral part of the KCGG/KCEG. TimertAUX1 may be included in the scheme to detect unsuccessful reclosures. Of coursethese auxiliary timers may already be in use with other K scheme options in whichcase they may be replaced by external delay on energisation timers such as theMVTT 14 or MVUA 11. In K Range series 2 relays only, auxililary timers tAUX3may be configured for delay on pick-up, or delay on drop-off and for this

21

MVAZ

Ia

CTslineTo

TCTC TC

282523

In

IbIc

RLY3

RELAY

10

9+

44

42


application it should be set for a delay on pick-up by setting link LOGB = 0(in K Range series 1 tAUX3 is always delayed on pick-up). Timers tAUX2 andtAUX3 are always delayed on pick-up.

14.2 Connections

The connection diagram for the scheme using the K Range relay auxiliary timers isshown in Figure 34.Equipment listDevice Function Device Function99-1,2 Multifunction protection FS-3 Close circuit fuseSW-1 Manual trip/close switch 52T CB trip coilSW-2 A/R in/out selector switch 52C CB close coilPB-1 Manual A/R reset push button AUX1 Unsuccessful reclose timer94 Electrically reset relay - MVAA 15 AUX2 Dead time52-a CB aux-open when CB open AUX3 Reclaim time52-b CB aux-closed when CB open AUX1-1 Unsuccessful reclose contactFS-1 Trip circuit fuse AUX2-1 CB close initiate contactFS-2 Protective relay circuit fuse AUX3-1 Successful reclose pulse contact

SW-1/1TOC

SW-1/2TOC

FS-3

FS-2

FS-1

52-b94-1

52-a

94-2

KCGG/KCEG99

CB Close -1

AUX1-1CB Close

BLOCK(99-t>>)

AUX2-1

AUX1

AUX2

AUX3

52C

52T

48V+ -

AUX3-1

13 14

99-1(t>, t>>, t>>>)

99-2(t>, t>>, t>>>)

In Out

Out InSW-2/1

PB-1

MVAA15

94S

R

-+

Figure 34: Connection diagram for single shot autoreclose scheme


1 2 3

99

52-a

52-b

94-1Aux2CB CloseAux3Aux1

14.3 Successful reclose description

When the protective relay operates (KCGG or KCEG) to trip the circuit breaker,the MVAA 15 (device 94) electrically reset relay is latched in, initiating theautoreclose sequence if the autoreclose service switch SW-2/1 is set to In Service.

1. Protection relay trips

2. AUX2 operates at end of dead time and closes breaker

3. AUX3 operates at end of reclaim time and resets scheme

Figure 35: Successful autoreclose sequence

The 94-1contact starts the AUX2 timer as the dead time of the scheme. At the endof the dead time, contact AUX2-1 operates to energise the local CB close input tothe KCGG relay, which in turn closes its contact CBClose-1 to energise the CBclose coil 52C. The CB Close function of the K Range relay includes a timer settingfor the duration of the close pulse to prevent burn out of the 52C coil.

The 94-1 contact may also be used, if desired, to block any one or all of theK range relay overcurrent stages by setting the appropriate input masks. The oneinput from 94-1 can then be programmed to initiate CB Close as well as initiateblocking.

As the 94-1 contact is latched in, as soon as the CB closes, the 52-a contact willclose to initiate the Aux3 timer as the reclaim time. If the breaker remains closedfor the duration of AUX3 reclaim time, the AUX3-1 contact operates to reset the 94relay which resets the complete scheme. A second contact may be programmedfor the AUX3 timer as a successful reclose pulse contact which will remain closedfor the reset time of 94 plus the reset time of AUX3.


1 2 3

99

52-a

52-b

94-1Aux2CB CloseAux3Aux1

4 5

14.4 Unsuccessful reclose

In the case of an unsuccessful reclose, a separate alarm is given by the AUX1timer.

1. Protection relay trips

2. AUX2 operates at end of dead time and closes breaker

3. Protection relay trips again within reclaim time

4. AUX1 raises unsuccessful reclose alarm

5. Scheme reset by manual push-button - CB can now be closed manually

Figure 36: Unsuccessful autoreclose sequence

As the 94-1 contact is latched in when the autoreclose is initated, if the breakerfails to close or fails to stay closed following the reclose pulse from CB Close-1, the52-b contact will initate the AUX1 timer. This timer is set slightly longer (eg. 2s)than the AUX2 Dead Time timer and raises the Unsuccessful Reclose alarm viaAUX1-1.

As a security against manual closing of the breaker either during a reclosesequence or if there has been an unsuccessful reclose, the 94-2 contact preventsthe manual close switch energising the 52C coil.

14.5 Blocking instantaneous low set protection when reclosing

When using autoreclose equipment it is often the practice to utilise I>>/Io>> asinstantaneous low set elements. This will ensure that any transient fault is quicklyextinguished so that the autoreclose can then re-establish the supplies. It may beconsidered an advantage to block the operation of the instantaneous elementsduring the reclose cycle to allow time graded tripping to determine and isolate thefaulted circuits, with the minimum disruption of supplies. As described in Chapter4, Section 5.5, it is advantageous to block the associated timers for the low setelements t>>/to>> to ensure accurate flagging of the fault. The output from timerAUX2 is shown in the diagram to perform this function as well as initiating theclose pulse timer. Setting link SD5 = 1 will result in the fault flags being resetautomatically following a successful reclosure.


Where lightning strikes are frequent, it can be an advantage to make theI>>/Io>> setting equal to I>/Io>, in order to detect the maximum number oftransient faults.

14.6 Circuit breaker operation counter

Each K Range series 2 relay is equipped with a circuit breaker operation counter,the value of which can be displayed on the LCD or remotely via the serialcommunication port. In addition an output relay can be arranged to pick-up whenthe counter value reaches a settable limit (see Chapter 5, Section 7.2). This countercan be used to augment the autoreclose scheme.



Relays

Service Manual

Chapter 5Measurement and Records


1. MEASURE 1 11.1 Current 11.2 Voltage 11.3 Frequency 12. MEASURE 2 12.1 Imax 12.2 Power 12.3 Power mode selection 22.4 Three phase power factor 23. MEASURE 3 33.1 Thermal ammeter 33.2 Thermal state 43.3 Peak demand 44. FAULT RECORDS 4 4.1 Generating fault records 54.2 Accessing fault records 54.3 Resetting fault records 54.4 Fault passage information 65. EVENT RECORDS 65.1 Triggering event records 65.2 Time tagging of event records 65.3 Accessing and resetting event records 7 6. DISTURBANCE RECORDS 76.1 Recorder control 76.2 Recorder capture 86.3 Recorder post trigger 86.4 Recorder logic trigger 86.5 Recorder relay trigger 86.6 Notes on recorded times 86.7 Disturbance recorder reset options 97. CIRCUIT BREAKER MAINTENANCE RECORDS 97.1 Circuit breaker clearance time 97.2 Circuit breaker operations counter 107.3 Circuit breaker contact duty 107.4 Circuit breaker maintenance alarm 108. ALARM RECORDS 118.1 Watchdog 118.1.1 Auxiliary powered relays 118.1.2 Dual powered relays 118.2 Trip indication 118.3 Alarm indication 11

Figure 1: Mode of signing power flow 2Figure 2: Record initiation logic 5Figure 3: Recorder reset 9Figure 4: Circuit breaker alarm 9


Section 1. MEASURE 1

The same menu cells have been retained for measurement values and new cellshave been used for any additional measurements that are now included.

1.1 Current

Current is measured once per power frequency cycle and Fourier is used to extractthe fundamental component. Measurements are made for each of the three phasecurrents (Ia, Ib, Ic) and the residual circuit current (Io). These values are stored inmenu cells 0201, 0202, 0203 and 0204 respectively.

1.2 Voltage

The phase/neutral voltages are measured directly when the internal VTs are starconnected. The phase voltages (Va, Vb, Vc) are then stored in menu locations0208, 0209 and 020A. From the sum of these voltages the residual voltage (Vo) iscalculated. This voltage is equivalent to the output that would be obtained from anopen delta connection of a three phase VT and is three times the zero sequencevoltage. The residual voltage Vo is stored in menu location 020B. The phasevoltages are calculated from the measured phase voltages and stored in menulocations 0205, 0206 and 0207.

In KCEU 142/242 the internal VTs are delta connected. The line voltages (Vab,Vbc, Vca) and the residual voltage (Vo) are then directly measured and stored intheir respective menu locations.

1.3 Frequency

The sampling frequency of the analogue/digital converter is synchronised to thepower system frequency when there is a signal of sufficient strength to reliablymake a frequency measurement. In the absence of a signal to frequency track thesampling frequency defaults to the power frequency setting in menu cell 0009.For protection functions the measured frequency defaults to the power frequencysetting when the current and voltage is zero. The displayed frequencymeasurement will also be the sampling frequency, but in this case it will read 0when the frequency tracking stops.


2.1 Imax

Imax is not a demand value, but the highest of the three phase currents and isstored in menu cell 0304. It is a useful value to display when all three phasecurrents cannot be displayed.

2.2 Power

Active and reactive power is calculated for each of the three phases and fromthese the three phase power is calculated. On series 1 relays only the three phasepower could be accessed, but on series 2 relays the single phase values are alsoavailable. All the power measurements are to be found under MEASURE 2.


2.3 Power mode selection

The standard current and voltage connections, shown on connection diagrams,follow the convention that forward current flows from the busbar to the feeder.This will correspond to positive values of active power flowing from the busbar tothe feeder. However, alternative methods of signing the direction of power flow areprovided to suit other application, or user’s standard. The signing for the activeand reactive power can be changed in menu cell 031E to any of the following fouralternatives:

Figure 1: Mode of signing power flow

When connected for forward power flow to the feeder then:

Mode 0 – Net export signing : + = net export of power and negative VArs

Mode 1 – Import to busbar : + = net power flow to busbar in (a+jB) form.

Mode 2 – Export from busbar : + = net power flow to feeder in (a+jB) form.

Mode 3 – Net import signing : + = net import of power and negative VArs

As a safeguard against accidental change this cell is password protected.

2.4 Three phase power factor

The three phase power factor is calculated after taking the selected signing modeinto account as follows:

pf = [active power]/[apparent power]

Range: –1<0<+1 [the sign (–/+) indicates reverse/forward and not lag/lead]

Mode 0 = ÐWMode 1 = +WMode 2 = ÐWMode 3 = +W

Power to busbar

Lagging kVArs to feederMode 0 = +VArMode 1 = +VArMode 2 = ÐVArMode 3 = ÐVAr

Lagging kVArs to busbarMode 0 = ÐVArMode 1 = ÐVArMode 2 = +VArMode 3 = +VAr

Power to feeder

Mode 1 = ÐWMode 2 = +WMode 3 = ÐW

Mode 0 = +W



3.1 Thermal ammeter

The thermal ammeters have a representative characteristic similar to that producedby a bi-metal type of instrument, where the movement would be proportional to thebending of the bi-metal strip as a result of the heat applied. Its time/positioncharacteristic is essentially exponential during the heating and cooling cycle andits response is measured in time constants.

This type of instrument does not respond to minor rises or dips in the measuredcurrent. It displays a steady measurement of the average current over the demandperiod, equal to six times the selected time constant. In the event of the auxiliarysupply to the relay being lost the thermal values are remembered and restoredwhen the supply is re-established.

The setting for the time constant is in menu cells 0614 and 0814 and is adjustablefrom 1 to 120 minutes in 1 minute steps. However, the time constant is shared withthe thermal protection and if the thermal protection is in use its time constantsettings will probably be given priority over the instrument requirements.

For some applications it may be found to be advantageous to allocate a differenttime constant in the group 1 and group 2 settings and to arrange for the settinggroup 2 to be selected in response to operation of one of the overcurrent stages.For example a different cooling time constant could be effective when a motor wasstationary and taking no current, to that when the cooling is increased bywindage.

UK applications

Electricity Supply Industry Specification ESI 50-2 states that the preferred time lagis 30 minutes and this shall be equal to 6 time constants. Thus for this applicationthe time constant should be set to 5 minutes.

US applications

In the USA the response of such devices is expressed as the time to reach 90% ofthe prospective current and the generally accepted time would seem to be in theorder of 15 minutes. The time to reach 90% of final value is 2.3 time constants andso for such applications the recommended time constant would be 15/2.3 = 6minutes.

Note: Link PF0 =1 for the thermal ammeters to operate.If PF0 = 0 then they will neither increment nor decrement.It is recommended that the thermal demand registers are manually reset tozero after setting PF0 = 0 as this will clear the thermal memory of theammeters.If link PF0 is set differently in the two setting groups, the thermal memorymay maintain a constant reading on the thermal ammeters after switchingto the setting group in which PF0 = 0.

The thermal ammeters cannot be directly reset by performing a reset cell operationon menu cell 0404, 0405 or 0406. They are password protected and only resetwhen the peak demand registers are reset (see Section 3.3).


3.2 Thermal state

The thermal state is a measure of the percentage of the limiting thermal capacitythat the protected item of plant is estimated to have reached. The maximum currentthat the device can withstand continuously should be entered as the setting for(Ith>) in the phase fault settings of the relay (cells 0613 and 0813). The timeconstant will compensate for the cooling effects resulting from heat being radiatedto the surroundings. When a current equal to Ith> is applied the thermal state willreach 100% after approximately 6 times the set time constant. Normal load currentwill be less than Ith> and the thermal state, being proportional to I2 will beconsiderably lower than 100%.

On loss of the auxiliary supply the thermal state is memorised and when the supplyis restored the thermal state is restored to the memorised value unless the storedvalue is greater than 90% when it will be restored to 90%. The thermal state isprotected and the password must be entered before it can be reset via the menu.Cell 0407 under MEASURE 3 should then be displayed and the [0] key pressedfor 1 second. This does not reset the thermal ammeters or the peak demand values.

The thermal state can also be reset by energising a logic input assigned in inputmask [0A11 RESET Ith]. Energising this input will reset the thermal state withoutresetting the peak demand ammeters. The password does not need to be enteredto reset by this method.

3.3 Peak demand

The peak demand is the highest value the thermal ammeters have attained sincethey were last reset and the demand for each phase is recorded separately.The peak demand can be reset by entering the password, selecting one of thepeak demand values in the menu, cells 040A, 040B, or 040C, and pressing thereset key [0]. This will also cause the thermal ammeters to reset at the same timebut the thermal state will not be reset.

Section 4. FAULT RECORDS

A full fault record is now stored for each of the last five faults, with the new recordoverwriting the oldest record one. These records are stored in non volatile memoryand are retained when the relay is powered down. Fault records contain thefollowing information:

– fault flags

– three line voltages

– measured phase currents

– residual current and voltage

– time from trip command to cessation of current flow

Fault records are also recorded with a time tag in the event recorded


4.1 Generating fault records

Figure 2: Record initiation logic

Fault records are generated when output relay RLY3, or a logic input assigned inthe input mask [0A09 EXT TRIP], is energised. The fault flags will be latched andthe trip LED lit in response to these two inputs. The circuit maintenance records willbe updated and the breaker fail protection initiated by either of these two inputs.

Relay RLY7 is used for remote, or manual trip, and can be arranged to trigger thegeneration of fault and circuit breaker maintenance records by setting linkLOGA = 1, but in this case the breaker fail protection will not be initiated.

Setting link LOG7 = 1 will enable the start relays to generate a fault record and sorecord the passage of fault current, but since if the fault is not cleared by this relayoperating output relay RLY3 or RLY7, the circuit breaker fail protection will not beinitiated, the trip LED will not be lit and the maintenance records will not beupdated.

4.2 Accessing fault records

Fault records can be accessed by selecting [0101 Fault No Fn] in the[FLT RECORD] column menu. The fault number (Fn) denotes the record for the lastfault and the record for previous faults can be selected by successive long pressesof the [0] key. Fn-1 is the previous fault and Fn-2 is the one before that, etc.

The [0] key enables fault record selection with the cover in place on the relay, butfor remote selection, the usual change setting commands will give a quickerresponse. With the cover removed and menu cell [0101 Fault NoFn] displayed,the [+] and [–] keys can be used to change to the required record number.

4.3 Resetting fault records

All five fault records can be cleared by selecting cell 0110, the last cell under faultrecords and pressing the [0] key for 1 second.

Note: If fault records are being viewed with ACCESS or PAS&T software; hitreturn key and then select the reset cell option to reset all five fault records.

Block start

LOG701

RLY701

LOGA

I>Io>

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

L TRIP

0A08

0A07

L CLOSE

01

SD2

0A09 EXT. TRIP

RLY3tBF

≥1

Close circuit breaker

Trip circuit breaker

Io<

I< 10

LOG2

tCLOSE

tTRIP

Reset01

LOG9

Generate circuit breaker maintenancerecords

Latch flagsGenerate fault records andCopy to events records

0B0D

0B0E

CB FAIL

CB CLOSE

CB TRIP7 6 5 4 3 2 1 0

0B0F7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0≥1

≥1

≥1

≥1

≥1

≥1≥1


4.4 Fault passage information

Any start function can be used to initiate a fault record when it detects the passageof fault current through the protected zone. This fault record will contain the currentmagnitude, the phases involved and voltage measurements, if appropriate.To achieve this it is necessary to set function link LOG 7 = 1 so that recording isinitiated by the start relays picking up. Several such records may be stored in theevent recorder and the number will be increased if the logging of logic events isturned off by setting link SD7 = 0.

If the fault records are also generated by relay RLY3 they will still be generated forfaults that are cleared by the relay tripping as well as for those passing through theprotected section. The disturbance recorder, if set to trigger when relay RLY3 picks-up, will only capture a record for faults cleared by RLY3 operating.

Section 5. EVENT RECORDS

Fifty time tagged event records can be stored, after which the oldest record isoverwritten. They are stored in volatile memory and will be lost if the relay ispowered down. The event records can only be accessed via the serialcommunication port and PC software is available to support the automaticextraction and storing of these records.

The following items are recorded by the event recorder:– Fault records including: fault flags, fault currents and voltages.– Setting changes made via the user interface on the front of the relay– Logic events: status change of logic inputs and/or output relays– Alarms: internal equipment alarms detected by self monitoring functions.

The number of full fault records that can be stored in events records can beincreased by setting link SD7 = 0 to inhibit storage of logic events.

5.1 Triggering event records

Event records are triggered automatically in response to the functions listed in theprevious section.

5.2 Time tagging of event records

The K Range relays do not have a real time clock. Instead, they each have a free-running 32-bit counter that increments every 1ms. When an event occurs, the valueof this millisecond counter is recorded (Ta) and stored in the event buffer.When the event is extracted, the present value of the millisecond counter is alsosent in the message (Tb). The master station must record the actual time at which itreceived the event message (Tc). This is equivalent to Tb if we consider thetransmission time of the event over the communication network to be negligible.It then calculates how long ago the event occurred by:

How long ago = (Tb – Ta) msReal time = (time message was received) – (how long ago it occurred)

= (Tc) – (Tb – Ta) ms

Time tagging is to a resolution of 1ms, the incrementation rate of the counter andremains valid for approximately 49 days. However, the crystal to control the timinghas a nominal accuracy of ±50 ppm, is not externally synchronised and has notemperature compensation. It can therefore introduce an error of ±1s in every 5.5hours.


The event recording was originally designed for use with automatic extractionprograms running on a personal computer (PC) when these timing errors would beinsignificant. Refer to Chapter 5, Section 6.6 for notes on recorded times, as theseapply equally to event records.

5.3 Accessing and resetting event records

Event records cannot be viewed on the relay and can only be accessed via theserial communication port of the relay. A PC with suitable software, such as PAS&T,can automatically extract the records, display them on a screen, print them, orstore them to either a floppy disk or to the hard disk of the computer.

When a new record is generated the oldest event record is automaticallyoverridden and the event flag set. The PAS&T software responds to this flag andextracts the record. When all records have been read, the event flag resets.

Section 6. DISTURBANCE RECORDS

The internal disturbance recorder has one channel allocated to each of themeasured analogue quantities; one to record the eight control inputs and one torecord the eight relay outputs. As with the event recorder, when the buffer is full theoldest record is overwritten and records are deleted if the auxiliary supply to therelay is removed. This ensures that when the buffer is read the contents will all bevalid.The disturbance recorder is stopped and the record frozen, a set time after aselected trigger has been activated. For example, a protection trip command couldbe the selected trigger and the delay would then set the duration of the trace afterthe fault.Each sample has a time tag attached to it so that when the waveform isreconstituted it can be plotted at the correct point against the time scale, thusensuring that the time base is correct and independent of the frequency.The K Range overcurrent relays measure eight samples per cycle, but the method ofrecording allows the analysis program to perform with records that may have adifferent sample rate.The disturbance recorder may be triggered by several different methods dependenton the settings in the RECORDER column of the menu. However, the records haveto be read via the serial communication port and suitable additional software isrequired to reconstruct and display the waveforms. Only one complete record isstored and the recorder must be reset before another record can be captured.

6.1 Recorder controlThis cell displays the state of the recorder :a) RUNNING – recorder storing data (overwriting oldest data)b) TRIGGERED – recorder stop delay triggeredc) STOPPED – recorder stopped and record ready for retrievalWhen this cell is selected, manual control is possible and to achieve this the relaymust be put into the setting mode by pressing the [+] key. A flashing cursor willthen appear on the bottom line of the display at the left-hand side. The [+] key willthen select 'running' and the [–] key will select 'triggered'. When the appropriatefunction has been selected the [F] key is pressed to accept the selection and theselected function will take effect when the [+] key is pressed to confirm theselection. To abort the selection at any stage, press the reset key [0].


6.2 Recorder capture

The recorder can capture:a) SAMPLES – the individual samplesb) MAGNITUDES – the Fourier derived amplitudesc) PHASES – the Fourier derived phase angles

The relay has no electro-mechanical adjustments, all calibration is effected insoftware and all three of the above options are used in the calibration process.For normal use as a fault recorder, SAMPLES will be the most useful.

However, for 60Hz systems there is less processing time available per cycle and ifall the protection functions have been activated the menu system, being the lowestpriority task, may appear very slow. To improve this the disturbance recordershould be stopped (triggered) via the menu. If records are still required at this timethen it is suggested that the recorder is set to record magnitudes rather thansamples because this will use less of the available processing time.

6.3 Recorder post trigger

The post trigger setting determines the length of the trace that occurs after the stoptrigger is received. This may be set to any value between 1 and 512 samples.When recording samples the total trace duration is 512/8 = 64 cycles becausethe interval between the samples is equivalent to one eighth of a cycle. However,the Fourier derived values are calculated once per cycle and so the total tracelength when recording these calculated phase or amplitude values is 512 cycles.

6.4 Recorder logic trigger

Any, or all, of the opto-isolated inputs may be used as the stop trigger and thetrigger may be taken from either the energisation or the de-energisation of theseinputs. The bottom line of the display for this cell will show a series of 16characters, each of which may be set to '1' or '0'. A '1' will select the input as atrigger and a '0' will deselect it.

The selection is made using the instructions for the setting links in Chapter 3,Section 3.4. The opto-isolated input (L0 to L7) associated with each digit is shownon the top line of the display for the digit underlined by the cursor. A '+' precedingit will indicate that the trigger will occur for energisation and a '–' will indicate thetrigger will occur for de-energisation.

6.5 Recorder relay trigger

Any, or all, of the output relays may be used as a stop trigger and the trigger maybe taken from either the energisation or the de-energisation of these outputs. Thebottom line of the display for this cell will show a series of 16 characters, each ofwhich may be set to '1' or '0'. A '1' will select the input and a '0' will deselect it.

The selection is made using the instructions for setting links in Chapter 3,Section 3.4. The output relay (RLY0 to RLY7) associated with each digit underlinedby the cursor is shown on the top line of the display. A '+' preceding it willindicate that the trigger will occur for energisation and a '–' will indicate thetrigger will occur for de-energisation.

6.6 Notes on recorded times

The times recorded for the opto-isolated inputs is the time at which the relayaccepted them as valid and responded to their selected control function. This willbe 12.5 ±2.5ms at 50Hz (10.4 ±2.1ms at 60Hz) after the opto-input wasenergised.


The time recorded for the output relays is the time at which the coil of the relay wasenergised and the contacts will close approximately 5ms later. Otherwise the timetags are generally to a resolution of 1ms for events and to a resolution of 1µs forthe samples values.

6.7 Disturbance recorder reset options

Figure 3: Recorder reset

The disturbance recorder is reset via cell [0C01 Control]. Alternatively it can bearranged to reset automatically, 3 seconds after the current is detected by theundercurrent elements to be above its set threshold. To select this option set linkSD6 = 1 and SD8 = 0. This automatic 3s reset may be useful when auto recloseequipment is employed since a record will only be stored when the autorecloseequipment fails to reclose the circuit breaker, or it locks out.

If a shorter or longer reset delay is required, set the links as follows. SD6 = 1 andSD8 = 1 (LOG3 = 0, LOG4 = 0) and then tAUX2 can be set to the necessary resetdelay. The setting range for tAUX2 is 0 to 24 days in graduated steps with thesmallest step of 10ms. With this option the recorder can be reset instantaneouslyby energising a logic input that is assigned in the input mask [0A0A AUX2].

Section 7. CIRCUIT BREAKER MAINTENANCE RECORDS

Figure 4: Circuit breaker alarm

7.1 Circuit breaker clearance time

The time taken for the circuit breaker to break the fault current is estimated andstored in the fault records in menu cell [0109 CB Trp Time]. A sudden increase inthis time measurement may indicate the need for maintenance of the circuitbreaker.

7 6 5 4 3 2 1 0

LOG3

Io<

I<10

10

LOG4

10

I<

SD8

AUX20A0B3SEC

tAUX2≥1&

≥1

SD501

SD80

SD60

1 1

AUX2

Reset trip flags

7 6 5 4 3 2 1 00B11

Recorderstopped

Reset disturbancerecorder

Recorderstopped

7 6 5 4 3 2 1 0

CB duty>

CB(ops)>0

LOG0

RLY3

EXT. TRIP0A09

Generate circuit breakermaintenance records

Latch red trip LED

≥1

7 6 5 4 3 2 1 0CB ALARM0B19

1

RLY7≥1

≥1


7.2 Circuit breaker operations counter

A register sums the number of circuit breaker operations and the value can beaccessed via menu cell 0310 under the column heading MEASURE 2. This recordis updated every time output relay RLY3 operates, or an opto input assigned ininput mask [0A09 EXT TRIP] is energised by an external trip. If link LOGA = 1 thenoperation of relay RLY7 will also be able to increment this register. RLY7 is normallyused for manual or remote trips via the trip pulse timer (tTRIP).

This function is inhibited if link LOG 0 = 0 and operative if LOG 0 =1.Incrementation of this counter can be blocked during testing by setting linkLOG 0 = 0.

The value of the counter can be reset to zero when it is displayed, by pressing thereset key [0]. Alternatively a reset cell command can be sent via the serialcommunication port. These cells are password protected and cannot be reset if thepassword has not been entered.

Note: Resetting the (CBops) counter will also result in the 'CBduty' registers beingreset at the same time.

7.3 Circuit breaker contact duty

Three registers are used to sum the contact breaking duty separately for eachphase. These are labelled [0311 CBdutyA], [0312 CBdutyB] and[0313 CBdutyC]. If link LOG 1=1 then the relay sums the current and it LOG 1=0then the relay sums the squared current. The value of these registers can beaccessed under the column heading MEASURE 2. These records are updatedevery time output relay RLY3 operates, if link LOGA = 1 and RLY7 operates, or anopto input assigned in input mask [0A09 EXT TRIP] is energised by an external trip.

When a remote trip is issued via the serial communications, or a local trip initiatedvia the input mask [0A07 LTrip] relay RLY7 should be assigned in output mask[0B0D CB Trip]. Then the contact duty record will also be updated when relayRLY7 operates if links LOG0 = 1, LOG1 = 0, LOGA = 1.

This function is inhibited if link LOG0 = 0 and operative if LOG1 = 1. Hence bysetting this link LOG0 = 0 during testing its incrementation can be blocked.

The value of these three registers can be reset to zero when any one of them isdisplayed, by pressing the reset key [0]. Alternatively a reset cell command can besent via the serial communication port. These cells are password protected andcannot be reset if the password has not been entered.

Note: Resetting the circuit breaker contact duty registers will also reset the circuitbreaker operations counter.

7.4 Circuit breaker maintenance alarm

A threshold can be set on the circuit breaker operations counter and the summatedcontact duty. The settings will be found in menu cells [0908 CBops>] and[0909 CBduty>1] under the LOGIC column heading. When the thresholds areexceeded the output mask [0B19 CB ALARM] will be energised and any relayassigned in this mask will pick-up to initiate an alarm. This is the only form of alarmthat is generated, except for the change in state of the output relay, which may berecorded in the event records if link SD7 = 1. The alarm will be inhibited if linkLOG 0=0, or if the output relay is de-selected in the relay mask.


Section 8. ALARM RECORDS

8.1 Watchdog

8.1.1 Auxiliary powered relays

The watchdog relay will pick up when the relay is operational to indicate a healthystate, with its make contact closed. When an alarm condition is detected thatrequires some action to be taken, the watchdog relay will reset and its breakcontact will close to give an alarm.

8.1.2 Dual powered relays

The watchdog relay operates in a slightly modified way on this version of the relay,because it does not initiate an alarm for loss of auxiliary power, as this may havebeen taken from an insecure source, or it may be powered solely from the currentcircuit. Operation of the watchdog is therefore inverted so that it will pick up for afailed condition, closing its make contact to give an alarm and in the normalcondition it will remain dropped off with its break contact closed to indicate ahealthy state.

The green LED will usually follow the operation of the watchdog in either of thesetwo cases. It will be lit when the relay is powered-up, operational and has notdetected any abnormal conditions.

The watchdog can be tested by setting alarm flag 6 to '1' in menu cell 0003 in theSYSTEM DATA column of the menu.

8.2 Trip indication

The trip LED will be lit following a trip condition where output relay RLY3 hasoperated, or a logic input that has been assigned in input mask [0A08 EXT TRIP]has been energised.

Relay RLY7 is generally reserved for remote trip initiation via the serialcommunication port. When link LOGA = 1 and relay RLY7 is assigned in outputmask [0B0D CB Trip] the trip LED will be lit if relay RLY7 has operated. Relay RLY7can also be initiated for manual trips via the trip pulse timer (tTRIP) by assigning alogic input in mask [0A07 LTrip] to give a trip indication. Unlike relay RLY3, RLY7does not initate the breaker fail protection, but they can both initiate the generationof fault records and hence fault flags. When relay RLY7 operates and linkLOGA = 1, the default display changes to the fault flag display and a letter 'R' isdisplayed in the extreme right-hand position on the bottom line of the display toindicate a 'remote trip'.

If link LOGA = 0 relay RLY7 can be freely assigned to any output function, withoutcreating a trip indication.

8.3 Alarm indication

The alarm LED will flash when the password has been entered. It will be lit andremain steady when an internal fault has been detected by its self test routine.The alarm flags can then be accessed to determine the fault, provided the relay isstill able to perform this function. See Chapter 3, Sections 3.5 and 3.6 for moreinformation on alarm flags.



Relays

Service Manual

Chapter 6Serial Communications


1. COURIER LANGUAGE AND PROTOCOL 12. K-BUS 12.1 K-Bus transmission layer 22.2 K-Bus connections 22.3 Ancillary equipment 33. SOFTWARE SUPPORT 33.1 Courier Access 33.2 PAS&T 33.3 K-Graph 43.4 CourierCom 43.5 PC requirements 43.6 Modem requirements 44. DATA FOR SYSTEM INTEGRATION 54.1 Differences between K Range series 1 and series 2 relays 54.2 Relay address 64.3 Measured values 64.4 Status word 64.5 Plant status word 74.6 Control status word 74.7 Logic input status word 74.8 Output relay status word 74.9 Alarm indications 84.10 Event records 84.11 Notes on recorded times 84.12 Protection flags 94.13 Fault records 104.14 Disturbance records 105. SETTING CONTROL 105.1 Remote setting change 115.2 Remote control of setting group 116. REMOTE OPERATION OF OUTPUT RELAYS 127. CIRCUIT BREAKER CONTROL 137.1 Remote control of circuit breaker 137.2 Local control of the circuit breaker 137.3 Safe manual closing of the circuit breaker 147.3.1 Closing the circuit breaker via the serial communication port 147.3.2 Closing the circuit breaker via a lead mounted push-button 147.3.3 Delayed manual closure of the circuit breaker 148. AIDS TO CIRCUIT BREAKER MAINTENANCE 15

Figure 1. Typical K-Bus connection diagram 2Figure 2. Circuit breaker control logic 13


Section 1. COURIER LANGUAGE AND PROTOCOL

Serial communications are supported over K-Bus, a multi-drop network that readilyinterfaces to IEC 60870-5 FT1.2 standards. The language and protocol used forcommunication is Courier. It has been especially developed to enable genericmaster station programs to access many different types of relay without thecontinual need to modify the master station program for each relay type. Therelays form a distributed data base and the master station polls the slave relays forany information required.This includes:

Measured valuesMenu textSettings and setting limitsFault recordsEvent recordsDisturbance recordsPlant status

Software is available to support both on-line and off-line setting changes to bemade and the automatic extraction and storage of event and disturbance recordsas described in Section 3.

Courier is designed to operate using a polled system, which prevents a slavedevice from communicating directly to a master control unit when it needs to informit that something has happened; it must wait until the master control unit requeststhe information. A feature of Courier is that each piece of information is packetedby preceding it with a ‘data type and length’ code. By knowing the format of thedata the receiving device can interpret it.

The Courier Communication Manual describes various aspects of this languageand other communication information necessary to interface these devices to otherequipment. It gives details on the hardware and software interfaces as well asguidelines on how additional devices should implement the Courier language soas to be consistent with all other devices.

Section 2. K-BUS

K-Bus is a communication system developed to connect remote slave devices to acentral master control unit, thus allowing remote control and monitoring functions tobe performed using an appropriate communication language. It is not designed toallow direct communication between slave devices, but merely between a mastercontrol unit and several slave devices. The main features of K-Bus are:cost effectiveness, high security, ease of installation and ease of use.

Each relay in the K Range has a serial communication port configured to K-Busstandards. K-Bus is a communication interface and protocol designed to meet therequirements of communication with protective relays and transducers within thepower system substation environment. It has the same reliability as the protectiverelays themselves and does not result in their performance being degraded in anyway. Error checking and noise rejection have been of major importance in itsdesign.


2.1 K-Bus transmission layer

The communication port is based on RS485 voltage transmission and receptionlevels with galvanic isolation provided by a transformer. A polled protocol is usedand no relay unit is allowed to transmit unless it receives a valid message,addressed to it without any detected error. Transmission is synchronous over a pairof screened wires and the data is FM0 coded with the clock signal to remove anydc component so that the signal will pass through transformers.

With the exception of the master units, each node in the network is passive andany failed unit on the system will not interfere with communication to the otherunits. The frame format is HDLC and the data rate is 64kbits/s.

2.2 K-Bus connections

Connection to the K-Bus port is by standard Midos 4mm screw terminals or snap-onconnectors. A twisted pair of wires is all that is required; the polarity of connectionis not important. It is recommended that an outer screen is used with an earthconnected to the screen at the master station end only. Termination of the screen iseffected with the “U” shaped terminal supplied and which has to be secured with aself tapping screw in the hole in the terminal block just below terminal 56, asshown in the diagram. Operation has been tested up to 32 units connected along1,000 metres of cable. The specification for suitable cable will be found in thetechnical data section. The method of encoding the data results in the polarity ofthe connection to the bus wiring being unimportant.

Note: K-Bus must be terminated with a 150Ω resistor at each end of the bus.The master station can be located at any position, but the bus should onlybe driven from one unit at a time.

Figure 1: Typical K-Bus connection diagram

K-BusScreened 2 core cable

5654

1


2.3 Ancillary equipment

The minimum requirement to communicate with the relay is a K-Bus/IEC 60870-5converter box type KITZ and suitable software to run on an IBM or compatiblepersonal computer.

RS232 interconnection lead for connecting the KITZ to a personal computer (PC)and software as described in Section 3.

Section 3. SOFTWARE SUPPORT

3.1 Courier Access

The Courier Access program is supplied with each KITZ and it allows on-lineaccess to any relay or other slave device on the system. It polls all availableaddresses on the bus to build a list of the active relays. Each relay can beprogrammed with a product description (16 characters) and a plant reference(16 characters).

A particular relay may then be chosen and accessed to display a table listing themenu column headings. Selecting a heading from the list and pressing the returnkey of the computer returns the full page of data that has been selected.

Selecting a setting from the displayed page and pressing the return key again willbring up the setting change box displaying the current setting value and themaximum and minimum limits of setting that have been extracted from the relay.A new setting may be typed in and entered. The new value will be sent to the relayand the relay will send back a copy of the data it received. If the returned valuematches what was sent, it is judged to have been received correctly and thedisplay asks for confirmation that the new setting is to be entered. When theexecution command is issued the relay checks the setting is within limits, stores it,then replies to state if the new value has been accepted, or rejected.

If the setting selected is password protected, the relay will reply that access isdenied. Any data received in error is automatically resent. Any data notunderstood, but received without error is ignored.

A complete setting file can be extracted from the relay and stored on disc andprinted out for record purposes. The stored settings can also be copied to otherrelays.

Control commands, such as close/trip of a circuit breaker, are actioned in thesame way as setting changes and can be achieved with this program by using thesetting change mechanism. This program supports modem connection but it cannotextract event or disturbance records.

3.2 PAS&T

The Protection Access Software and Toolkit (PAS&T) program performs all thefunctions described for the Courier Access program, but additionally it can performthe following functions:

– Generate a table of all circuit breakers that can be controlled via the relaysconnected to K-Bus. These are listed by their plant reference and their open/closed status is displayed. Selecting a circuit breaker from this table enables itto be controlled with all the background security described for setting changes.

– Automatically extracts event records, displays them on screen, prints, or storesthem to disc.


– Automatically extracts disturbance records and stores them to disc inCOMTRADE format.

– Poll the relay for selected data at set intervals and displays the values on screen,or stores a selected number of values that it can plot on screen to show trendinformation.

– Display coded or decoded messages on screen to help de-bug thecommunication system.

– The auto-addressing feature allocates the next available address on the bus to anew relay.

3.3 K-Graph

This program, supplied with PAS&T, can display disturbance records and printthem. The COMTRADE format in which the files are stored can also be loaded intoan Excel, or similar spreadsheet program.

3.4 Courier-Com

Courier-Com is a Windows based setting program that can be used off-line,ie. without the relays being connected. Setting files can be generated in the officeand taken to site on floppy disc for loading to the relays. This program can beused to down-load the settings to the relay, alternatively ACCESS or PAS&T may beused.

3.5 PC requirements

To operate fully, the above programs require:

IBM PC/XT/AT/PS2 or true compatible.640kB of main memory RAMGraphics adapter CGA, EGA, VGA or MDASerial adapter port configured as COM1 or COM2 (RS232)Floppy disk drive 3.5 inchMS-DOS 3.2 or later/IBM PC-DOS 3.2 or laterParallel printer port for optional printer.

Additional equipment

PrinterRS-232 link.KITZ 101 K-Bus/ RS232 communication interface.Modem

3.6 Modem requirements

ALSTOM T&D Protection & Control Ltd have adopted the IEC 60870-5 ft1.2 frameformat for transmitting the courier communication language over RS-232 basedsystems, which includes transmission over modems.

The IEC 60870-5 ft1.2 specification calls for an 11-bit frame format consisting of 1start bit, 8 data bits, 1 even parity bit and 1 stop bit. However, most modemscannot support this 11-bit frame format, so a relaxed 10-bit frame format issupported by the Protection Access Software & Toolkit and by the KITZ, consistingof 1 start bit 8 data bits, no parity and 1 stop bit.


Although Courier and IEC 60870 both have inherent error detection, the paritychecking on each individual character in the 11-bit frame provides additionalsecurity and is a requirement of IEC 60870 in order to meet the error rate levels itguarantees. It is therefore recommended that modems should be used whichsupport these 11-bit frames.

The following modem has been evaluated for use with the full IEC 60870 ft1.2protocol and is recommended for use:

Motorola Codex 3265 or 3265 Fast

Other modems may be used provided that the following features are available;refer to the modem documentation for details on setting these features:

– Support for an 11 bit frame (1 start bit, 8 data bits, 1 even parity bit and 1 stopbit). This feature is not required if the 10-bit frame format is chosen.

– Facility to disable all error correction, data compression, speed buffering orautomatic speed changes.

– It must be possible to save all the settings required to achieve a connection innon-volatile memory. This feature is only required for modems at the outstationend of the link.

Notes:1. The V23 asymmetric data rate (1200/75bits/s) is not supported

2. Modems made by Hayes do not support 11 bit characters.

Section 4. DATA FOR SYSTEM INTEGRATION

4.1 Differences between K Range series 1 and series 2 relays

As far as system integration is concerned there should be little difference betweenrelays from series 1 and series 2. However, the following should be noted:

Changing the communication address is now password protected for addedsecurity and to change the address the password must first be entered. This doesnot apply to the auto-addressing facility available within the Courier language thatwill apply the next available address on the bus to a relay set to address 0, nor thenew address feature that allows a relay to be directly addressed by serial numbersent to the global address 255. Both auto-addressing and direct addressing byserial number are supported by PAS&T, but direct addressing by serial number isalso supported by Courier Access.

Measurement functions retain their original cell references and some additionalmeasurements will be available on the K Range series 2 relays.

The data under fault records has been rearranged to enable five full fault recordsto be stored. The menu cell references for these have changed and referenceshould be made to Chapter 3, Section 6 for the new cell locations. A notablechange is that the circuit breaker operation time which was stored in menu cell0109 is now to be found in menu cell 010B.

Additional input masks and output masks have also been generated for the newfunctions and this has resulted in them being renumbered.

Software function links have been added for the new functions and they must beset to “1” in order to select the new features. Previously these links were unused


and hence set to “0” by default. The functions of some existing links have beenchanged. Reference should be made to the logic diagrams to determine how theyshould be set for series 2 relays.

Application setting files for series 1 relays will require some modification beforethey can be used with series 2 relays.

4.2 Relay address

The relay can have any address from 1 to 254 inclusive. Address 255 is theglobal address that all relays, or other slave devices, respond to. The Courierprotocol specifies that no reply shall be issued by a slave device in response to aglobal message. This is to prevent all devices responding and causing contentionon the bus.

Each relay is supplied with its address set to 255 to ensure that when connected toan operational network it will not have a conflicting address with another devicethat is already operational. To make the new device fully operational it must haveits address set. The address can be changed manually by entering the passwordand changing the address by the setting change method via the user interface onthe front of the relay.

Alternatively, if the software running on the PC supports auto-addressing, the relayaddress can be set to 0 and the auto-addressing feature of the PC software turnedon. The relay will then be automatically set to the next available address on thebus. PAS&T software supports both these features.

If the address is 255, or unknown, the device address can be changed by sendinga new address, in a global message, to a device with a particular serial number.This method (supported by PAS&T, Courier Access and Courier-Com) is useful fordevices that are not provided with a user interface with which to read or changethe current address.

4.3 Measured values

Any measured value can be extracted periodically by polling the relay. Measuredvalues are stored in the same menu locations in the KCGG/KCEG/KCEU relaysand the KMPC measurement centre.

4.4 Status word

A status byte is contained in every reply from a slave device. This is returned bythe relay at the start of every message to signal important data on which themaster station may be designed to respond automatically.

The flags contained are:

Bit 0 – 1 = Disturbance record available for collectionBit 1 – 1 = Plant status word changedBit 2 – 1 = Control status word changedBit 3 – 1 = Relay busy, cannot complete reply in timeBit 4 – 1 = Relay out of serviceBit 5 – 1 = Event record available for retrievalBit 6 – 1 = Alarm LED litBit 7 – 1 = Trip LED lit

Bits 6 and 7 are used to mimic the trip and alarm indication on the frontplate ofthe slave devices. They cannot be used to extract fault and alarm information froma slave device because they cannot be guaranteed to be set for a long enoughperiod to be identified.


Bits 5 and 0 enable the master station to respond automatically and extract eventrecords and disturbance records, if they are so programmed.

4.5 Plant status word

The plant status word can be found at menu location 000C and each pair of bitsin the plant status word is used to indicate the status (position) of items of plantcontrolled via the relay.

Only the circuit breaker can be controlled via the relays described in this servicemanual and the associated bits in the plant status word are defined as follows:

Bit 1 Bit 0 – Circuit breaker 1

0 0 – No CB connected (auxiliary CB1 contacts faulty)0 1 – CB1 open1 0 – CB1 closed1 1 – Auxiliary CB1 contacts or wiring faulty

Bit 8 Bit 9 – Circuit breaker 2

0 0 – No CB connected (auxiliary CB2 contacts faulty)0 1 – CB2 open1 0 – CB2 closed1 1 – Auxiliary CB2 contacts or wiring faulty

The master PAS&T control unit software makes use of this information to generate atable of all the circuit breakers and isolators that can be controlled and to showtheir current status.

To make this information available to the master control unit it is necessary toallocate a logic input that will be energised when the circuit breaker is closed ininput mask [0A0E CB CLOSED IND] and one that is energised when the circuitbreaker is open in input mask [0A0F CB OPEN IND]. Bits 0 and 1 will thenindicate the position of the circuit breaker.

If the circuit breaker can be racked into one of two positions, such that it can beconnected to busbar 1 or busbar 2, then a third logic input that will be energisedwhen the circuit breaker is connected to busbar 2 must be assigned in the inputmask [0A10 CB BUS 2]. The circuit breaker open/closed states will then betransferred to bits 8 and 9 when the circuit breaker is in position for connecting thefeeder to busbar 2. The circuit breaker can then be controlled with the appropriateopen and close commands.

4.6 Control status word

The control status word will be found in menu cell 000D. It is used to transfercontrol information from the slave device to the master control unit. However, therelays described in this manual are protection relays and this feature is not used.

4.7 Logic input status word

The status of the logic control inputs can be observed by polling menu cell 0020,where the lowest 8 bits of the returned value indicates the status of each of the 8logic inputs. This cell is read only.

4.8 Output relay status word

The status of the output relays can be observed by polling menu cell 0021, wherethe lowest 8 bits of the returned value indicates the status of each of the 8 outputrelays. This cell is read only.


4.9 Alarm indications

The status of the internal alarms produced by the relays self test routine can beobserved by polling menu cell 0022, where the lowest 7 bits of the returned valueindicate the status of each of the alarms. Bit 6 can be set/reset, in order to test thewatchdog relay. No other control actions are possible on this cell.

Bit 0 Error in factory configuration detected (relay inoperative)Bit 1 Error in calibration detected (relay running in uncalibrated state)Bit 2 Error detected in storage settings (relay operationsal, check settings)Bit 3 No service (protection out of service)Bit 4 No samples (A/D converter not sampling)Bit 5 No Fourier (Fourier routine not being performed)Bit 6 Test watchdog (set to 1 to test and rest to 0 afterwards)

4.10 Event records

An event may be a change of state of a control input or an output relay. It may bea setting that has been changed locally or a protection or control function that hasperformed its intended function. A total of 50 events may be stored in a buffer,each with an associated time tag. This time tag is the value of a timer counter thatis incremented every 1ms.

The event records can only be accessed via the serial communication port whenthe relay is connected to a suitable master station. When the relay is not connectedto a master station the event records can still be extracted within certain limitations:

– The event records can only be read via the serial communication port and aK-Bus/IEC 60870-5 interface unit will be required to enable the serial port to beconnected to an IBM or compatible PC. Suitable software will be required to runon the PC so that the records can be extracted.

– When the event buffer becomes full the oldest record is overwritten by the nextevent.

– Records are deleted when the auxiliary supply to the relay is removed, to ensurethat the buffer does not contain invalid data. Dual powered relays are mostlikely to be affected.

– The time tag will be valid for 49 days assuming that the auxiliary supply has notbeen lost within that time. However, there may be an error of ±4.3s in every 24hour period due to the accuracy limits of the crystal. This is not a problem whena master station is on line as the relays will usually be polled once every secondor so.

The contents of the event record are documented in Chapter 5, Section 5.

4.11 Notes on recorded times

As described in Chapter 5, Section 5.2, the event records are appended with thevalue of a 1 millisecond counter and the current value of the counter is appendedto the start of each reply form a relay. Thus it is possible to calculate how long agothe event took place and subtract this from the current value of the real time clockin the PC.

If transmission is to be over a modem there will be additional delays in thecommunication path. In which case the KITZ can be selected to append the realtime at which the message was sent and this value can then be used in the


conversion of the time tags. With this method of time tagging, the time tags for allrelays on K-Bus will be accurate, relative to each other, regardless of the accuracyof the relay time clock.

See also Chapter 5, Section 6.6 for additional information on time taggingaccuracy.

4.12 Protection flags

The protection flags hold the status of the various protection elements in the relayand it is from these that the fault flags are generated. They are transmitted in theevent records as part of a fault record and this is the only way they can beaccessed.

The following table lists the protection flags:Bit position Hexadecimal mask Protection function

0 0x00000001L PhA lowset trip1 0x00000002L PhB lowset trip2 0x00000004L PhC lowset trip3 0x00000008L E/F lowset trip4 0x00000010L PhA 1st highset trip5 0x00000020L PhB 1st highset trip6 0x00000040L PhC 1st highset trip7 0x00000080L E/F 1st highset trip8 0x00000100L PhA 2nd highset trip9 0x00000200L PhB 2nd highset trip10 0x00000400L PhC 2nd highset trip11 0x00000800L E/F 2nd highset trip12 0x00001000L PhA lowset forward/normal start13 0x00002000L PhB lowset forward/normal start14 0x00004000L PhC lowset forward/normal start15 0x00008000L E/F lowset forward/normal start16 0x00010000L PhA lowset reverse start17 0x00020000L PhB lowset reverse start18 0x00040000L PhC lowset reverse start19 0x00080000L E/F lowset reverse start20 0x00100000L Thermal overload21 0x00200000L Phase undercurrent trip22 0x00400000L Undervoltage trip23 0x00800000L Manual remote CB trip24 0x01000000L AUX1 trip25 0x02000000L AUX2 trip26 0x04000000L AUX3 trip27 0x08000000L Manual remote CB close28 0x10000000L Breaker fail trip29 0x20000000L Trip occurred in GROUP 2 settings30 0x40000000L E/F Undercurrent trip31 0x80000000L Thermal overload alarm

This 32 bit word can be found in packet #4 of the event record as the menu cellvalue. A decoded text form can be found in packet #3 as the ASCII Text Descriptionof the event (refer to Courier User Manual). The value can be decoded to establishwhich elements were operated at the time of the event. The bit position is identicalfor K Range series 1 and series 2 relays with the exception of following bits:

– Bit 20 for series 1 relays indicated cold load start; for series 2 relays thisfunction is transferred to AUX3 and bit 20 now indicates operation of thethermal overload element.

– Bit 31 for series 1 relays was not used. For series 2 relays bit 31 indicates theoperation of the thermal overload alarm element.


4.13 Fault records

Although fault records are stored in the event records and they may be extracted inthis way, it may be necessary in some instances to extract the fault records directly.To do this, the record number must be first entered in menu cell 0101 so that thecorrect fault record can be extracted. Fn is the record for the last fault; Fn-1 is theprevious fault record and Fn-4 is the oldest record. Then the values for menucolumn 01 should be requested.

The Courier User Guide gives the detailed commands associated with thesefunctions.

4.14 Disturbance records

The procedure for setting up the disturbance recorder in the relays, is fullydescribed in Chapter 5, Section 6 of this manual. If the extraction of these recordsis to be incorporated in some bespoke software program reference should bemade to the Courier User Guide for the relevant commands that are necessary toextract the records.

It is recommended that all such records are stored in a Comtrade format to enablecommercially available programs to use the files. Comtrade includes minimum andmaximum values for each analogue chanel. In all K Range relays these are 0 and32767.

Section 5. SETTING CONTROL

Control functions via a K Range relay can be performed over the serialcommunication link. They include change of individual relay settings, change ofsetting groups, remote control of the circuit breaker, and operation and latchingselected output relays.

Remote control is restricted to those functions that have been selected in the relaysmenu table and the selection cannot be changed without entering the password.CRC and message length checks are used on each message received. Noresponse is given for received messages with a detected error. The master stationcan be set to resend a command a set number of times if it does not receive areply or receives a reply with a detected error.

Note: Control commands are generally performed by changing the value of a celland are actioned by the setting change procedure, as described in Chapter6, 3.1, and have the same inherent security. No replies are permitted forglobal commands as these would cause contention on the bus; instead adouble send is used for verification of the message by the relay for this typeof command. Confirmation that a control command, or setting change, hasbeen accepted is issued by the relay and an error message is returnedwhen it is rejected.

The command to change setting group does not give an error messagewhen the group 2 settings are disabled unless link SD3=0 to inhibitresponse to a remote setting group change commands.


5.1 Remote setting change

The relay will only respond to setting change commands via the serial port if linkSD0=1. Setting SD0=0 inhibits all remote setting changes with the exception of theSD software links and the password entry. Thus, with link SD0=0, remote settingchanges are password protected.

To change them, the password must be remotely entered and the function link SDfunction link SD0 set to “1” to enable remote setting changes. When all settingchanges have been made, set link SD0=0 to restore password protection to remotesetting changes.

5.2 Remote control of setting group

The setting group selection is fully described in Chapter 4, Section 12.1 includingthe remote control of this function. Group 2 must be activated before it can beselected by setting software link SD4=1. Set link SD3=1 to enable the relay torespond to change setting group commands, via the serial port to select group 2and set SD4=1 to inhibit this function.

If the remote setting changes have been selected to have password protection, asdescribed in Section 5.1, then it can also be applied to the remote setting groupselection as follows. Set link SD3=0 to inhibit remote setting changes, then set linkSD0=1 to enable remote setting changes and set link LOG8=1. The group 2settings will then be in operation and setting link SD0=0 will restore the passwordprotection.

If conventional SCADA has an output relay assigned to select the alternative settinggroup then it may be used to energise a logic input assigned in the input mask[0A0D STG GRP 2]. In this case set link SD3=0.


Section 6. REMOTE OPERATION OF OUTPUT RELAYS

K Range series 2 relays (except for KCEU) respond to the load shed by levelCourier commands. These were intended to be used to control the load sheddingcontrol of conventional voltage regulating relays and can of course still be used forthat purpose. However, it also provides a way of remotely operating and latchingselected output relays. In the following example it is assumed that relays areallocated in the load shedding output masks as follows:

RLY0 assigned in [0B14 LEVEL 1]RLY1 assigned in [0B15 LEVEL 2]RLY2 assigned in [0B16 LEVEL 3]

The following truth table then applies:

Command RLY 0 RLY 1 RLY 3

Load shed to level 0 0 0 0




If the relays are assigned as follows :

RLY0 assigned in [0B14 LEVEL 1]RLY1 assigned in [0B15 LEVEL 2]RLY0, RLY1 & RLY2 assigned in [0B16 LEVEL 3]

The truth table would read:

Command RLY 0 RLY 1 RLY 3





The relays will retain their selected state until a new command is received.The settings will be stored when the relay is powered-down and restored again onpower-up. This allows these particular outputs to be used to select other functionssuch as block sensitive earth fault, or inhibit instantaneous low set overcurrentelements.


Section 7. CIRCUIT BREAKER CONTROL

To set-up the relay for circuit breaker control, relay RLY7 must be assigned in outputmask [0B0D CB TRIP] and RLY6 in output mask [0B0E CB CLOSE].Some circuit breakers require the closing pulse to be interrupted when a tripcommand is issued during the closing sequence, such as when closing onto a fault.This is to prevent pumping of the circuit breaker, ie. reclosing again when the tripsignal is terminated, and it can be arranged by setting link LOG9 = 1. Some othertypes of circuit breaker require the close pulse to be maintained and to achievethis, set link LOG9 = 0.

Figure 2: Circuit breaker control logic

7.1 Remote control of circuit breaker

Set link SD2=1 to enable remote control of the circuit breaker. The ACCESS,PAS&T, or other suitable program that supports this feature can then be used toperform the remote control of this plant item. When using PAS&T, logic inputs mustbe assigned in input masks [0A0E CB CLOSED IND] and [0A0F CB OPEN IND]to indicate the status of the circuit breaker so that a table of circuit breakers andtheir status can be generated. If the circuit breaker can be racked into analternative position, such that it can then be connected to busbar 2 instead ofbusbar 1, then a logic input must be assigned in mask [0A10 CB BUS2] if thisinformation is required to be displayed by PAS&T.

Password protection for remote circuit breaker control can be applied as follows.Set link SD2=0 to inhibit remote changes. To make a remote change, enter thepassword, set link SD2=1, and send the command to control the circuit breaker.Then to re-establish password protection set link SD2=0 again.

7.2 Local control of the circuit breaker

If local controls are routed to the circuit breaker via the logic inputs assigned inmasks [0A07 Ltrip] and [0A08 Lclose], the circuit breaker maintenance recordswill be updated for local control of the circuit breaker. In this case it will be theaction of relay RLY7 operating that causes the record to be incremented asdescribed in Chapter 5, Section 4.1.

Block start

LOG701

RLY701

LOGA

I>Io>

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

L TRIP

0A08

0A07

L CLOSE

01

SD2

0A09 EXT. TRIP

RLY3tBF

≥1



Io<

I< 10

LOG2

tCLOSE

tTRIP

Reset01

LOG9

Generate circuit breaker maintenancerecords

Latch flagsGenerate fault records andCopy to events records

0B0D

0B0E

CB FAIL

CB CLOSE

CB TRIP7 6 5 4 3 2 1 0

0B0F7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0≥1

≥1

≥1

≥1

≥1

≥1≥1


7.3 Safe manual closing of the circuit breaker

There have been instances of injury to personnel when closing a circuit breakeronto a fault. So, from a health and safety point of view, it is sometimes considerednecessary to manually close the circuit breaker from a safe distance. This isparticularly important, when the autoreclose has locked-out, or after maintenanceon the primary plant when temporary earth clamps may have been left connected.

If the closure of the circuit breaker is routed via the KCGG/KCEG/KCEU relay,any of the following procedures may be considered:

7.3.1 Closing the circuit breaker via the serial communication port

If the serial port of the relay has no connections made to it, then the terminals 54and 56 can be connected to a jack plug on the front of the panel. To close thecircuit breaker from a safe distance it is then only necessary to plug in anextension lead and connect it to a laptop computer. The circuit breaker can then beclosed as described in Section 7.1.

7.3.2 Closing the circuit breaker via a lead mounted push-button

A spare logic input of the relay can be wired, via the field voltage supply of therelay, to a plug that is mounted on the panel of the cubicle. In this case a jack plugis not advised because the two terminals may be temporarily short circuited whenthe plug is being inserted. This logic input is then assigned in the input mask[0A08 Lclose].

To operate the circuit breaker an extension lead is plugged into the socket and alead mounted push-button at the other end is then pressed to initiate a pulse offixed duration to close the circuit breaker. For extra security, one of the auxiliarytimers may be connected in the control path, so that the push-button has to bepressed for the set time of the timer before the circuit breaker will close.

7.3.3 Delayed manual closure of the circuit breaker

If auxiliary timer tAUX3 is not being used for some other purpose and either tAUX1or tAUX2 is also available then proceed as follows:

1. Set link LOGB = 1 to give tAUX3 a delay on drop-off.

2. Allocate an output relay in mask [0B12 AUX3] and connect its contact to aspare logic input.

3. Assign this logic input in input mask [0A0A AUX1] to start tAUX1 or [0A0CAUX2] to start tAUX2.

4. Assign an output relay in mask [0B10 AUX1] or [0B11 AUX2] depending onthe timer to be used.

5. Energise a logic input via the contact of this output relay and assign it in inputmask [0A08 Lclose] to initiate the closing pulse.

6. Allocate a logic input in mask [0A0C AUX3] and arrange for this to beenergised via a switch (preferably a key switch) that is spring loaded in the offposition.

When the initiating switch is closed momentarily timer tAUX3 will pick-up its outputrelay which will remain picked-up for the set time of tAUX3. Timer tAUX1 (ortAUX2) will be picked up by the output relay assigned to tAUX3 and when it timesout it will pick-up a relay that triggers the close pulse via the Lclose input. The timesetting for tAUX1 (ortAUX2) should be the required delay and tAUX3 should be set2 seconds longer. When tAUX3 times out the circuit resets.


The close sequence can be interrupted by breaking the link, from the output oftAUX3 to the logic input initiating tAUX1 (or tAUX2, whichever is being used), witha push-button or an alternative position on the key switch. Note that these timershave very wide setting ranges and that the delay is in the order of 20 to 30seconds only.

Where no auxiliary timers are available the close pulse could be initiated byenergising a logic input assigned in the input mask [0A08 Lclose] via a pushbutton connected via a twisted pair of wires of sufficient length. If an auxiliarytimer is available and is connected in the initiating path it would add to thesecurity.

Section 8. AIDS TO CIRCUIT BREAKER MAINTENANCE

The information gathered by the relay can be of assistance in determining the needfor circuit breaker maintenance. The circuit breaker opening time is recorded underFAULT RECORDS. If this value is monitored, any significant increase may be usedas an indication that circuit breaker maintenance is required.

Additionally the number of circuit breaker operations is recorded underMEASUREMENTS (2). An indication of the summated contact breaking duty whichis recorded separately for each phase will also be found under this heading.



Relays

Service Manual

Chapter 7Technical Data


1. RATINGS 11.1 Inputs 11.2 Outputs 12. BURDENS 22.1 Current circuits 22.2 Reference voltage 22.3 Auxiliary voltage 32.4 Opto-isolated inputs 33. OVERCURRENT SETTING RANGES 33.1 Auxiliary powered relays 33.2 Dual powered relays 34. TIME SETTING RANGES 44.1 Inverse definite minimum time (IDMT) 44.2 Definite independent time 54.3 Auxiliary time delays 55. OTHER PROTECTION SETTINGS 55.1 Directional 55.2 Thermal 55.3 Undervoltage 65.4 Underfrequency 65.5 Ratios 66. MEASUREMENT (DISPLAYED) 67. ACCURACY 67.1 Reference conditions 67.2 Current 67.3 Time delays 77.4 Directional 77.5 Thermal 77.6 Undervoltage 77.7 Under frequency 77.8 Auxiliary timers 87.9 Measurements 88. INFLUENCING QUANTITIES 88.1 Ambient temperature 88.2 Frequency 88.2.1 With frequency tracking 88.2.2 Without frequency tracking (KCGG 122 KCEG 112) 88.3 Auxiliary supply 98.4 System X/R 99. OPTO-ISOLATED INPUTS 910. Output Relays 1010.1 Output relays 0 to 7 1010.2 Watchdog 1011. OPERATION INDICATOR 1012. COMMUNICATION PORT 1013. CURRENT TRANSFORMER REQUIREMENTS 1014. HIGH VOLTAGE WITHSTAND 12


14.1 Dielectric withstand IEC 60255-5: 1977 1214.2 High voltage impulse IEC 60255-5: 1977 1214.3 Insulation resistance IEC 60255-5: 1977 1214.4 High frequency disturbance IEC 60255-22-1: 1988 1214.5 Fast transient IEC 60255-22-4: 1992 1214.6 EMC compliance 1214.7 Electrostatic discharge test IEC 60255-22-2: 1996 1215. IEEE/ANSI SPECIFICATIONS 1315.1 Standard for relay systems associated with electrical power apparatus 1315.2 Surge withstand capability 1315.3 Radio electromagnetic interference 1316. ENVIRONMENTAL 1316.1 Temperature IEC 60255-6: 1988 1316.2 Humidity IEC 60068-2-3: 1969 1316.3 Enclosure protection IEC 60529:1989 1316.4 Vibration IEC 60255-21-1:1988 1316.5 Shock and bump IEC 60255-21 2:1988 1316.6 Seismic IEC 60255-21-3:1993 1317. MODEL NUMBERS 1418. FREQUENCY RESPONSE 1618.1 Transient overreach 1718.2 Peak measurement 1718.3 Frequency response of directional elements 18

Figure 1: Response of Fourier filtering 16Figure 2: Response when frequency tracking 17Figure 3: Frequency response when relay responds to both peak and Fourier values 18


Section 1. RATINGS

1.1 Inputs

Current input Rated (In) Continuous 3s 1s(In) (A) (xIn) (xIn) (A)

Auxiliary powered 1 3.2 30 1005 3.2 30 400

Dual powered 1 2.4 30 1005 2.4 30 400

Voltage input Rated (Vn) Continuous 10s(Line) (V) (xVn) (xVn)

110 4 5.4440 2 2.6

Operative range

Auxiliary voltage Rated voltage DC supply AC supply Crest (Vx) (V) (V) (V) (V)

Auxiliary powered 24-125 19-150 50-133 19048-250 33-300 87-265 380

Dual powered 100-250 60-300 60-265 380

Frequency Nominal rating Operative range(Fn) (Hz) (Hz)

Frequency tracking 50 or 60 45-65

Non-tracking 50 47-52.5

Non tracking 60 57-63

Rating Off state On state(Vdc) (Vdc) (Vdc)

Logic inputs 50 ≤12 ≥35

1.2 Outputs

Field Voltage 48V dc (Current limited to 60mA)

Capacitor Trip 50V dc (680µF capacitor - Energy = 0.85J)


Section 2. BURDENS

2.1 Current circuits

Auxiliary powered Phase Earth(1) SEF(2) Conditions

In = 1A 0.06 0.06 0.08 ohms at InIn = 1A 0.06 0.06 0.06 ohms at 30InIn = 5A 0.006 0.006 0.006 ohms at InIn = 5A 0.006 0.006 0.006 ohms at 30In

Dual powered Phase Earth SEF

In=1A 0.58 2.7 2.6 ohms at 0.5In for Vx =110V0.45 2.3 2.2 ohms at 1.0In for Vx = 110V0.37 2.0 2.0 ohms at 2.0In for Vx = 110V0.33 1.9 1.8 ohms at 5.0In for Vx = 110V0.31 1.9 1.7 ohms at 10In for Vx = 110V0.31 1.9 1.7 ohms at 20In for Vx = 110V0.31 1.7 1.5 ohms at 30In for Vx = 110V

In=1A 8.1 27.3 29.9 ohms at 0.5In for Vx = 0V5.4 11.4 12.4 ohms at 1.0In for Vx = 0V2.1 5.2 5.6 ohms at 2.0In for Vx = 0V0.8 2.6 2.6 ohms at 5.0In for Vx = 0V0.46 2.0 2.0 ohms at 10In for Vx = 0V0.35 1.8 1.8 ohms at 20In for Vx = 0V0.32 1.6 1.6 ohms at 30In for Vx = 0V



Note 1: For standard and special earth fault settings in KCEG relays

Note 2: For sensitive earth fault settings in KCEG 112/152 and KCEU relays

2.2 Reference voltage

Vn = 110V 0.02VA @ 110V phase/phaseVn = 440V 0.08VA @ 440V phase/phase


2.3 Auxiliary voltage

DC supply 2.5 – 6.0W at Vx max with no output relays or logic inputs energized4.0 – 8.0W at Vx max with 2 output relays & 2 logic inputs energized5.5 – 12W at Vx max with all output relays & logic inputs energized

AC supply 6.0 – 12VA at Vx max with no output relays or logic inputs energized6.0 – 14VA at Vx max with 2 output relays & 2 logic inputs energized13 – 23VA at Vx max with all output relays & logic inputs energized

2.4 Opto-isolated inputs

DC supply 0.25W per input (50V 10kΩ)

Section 3. OVERCURRENT SETTING RANGES

3.1 Auxiliary powered relays

Threshold (Is) Step size

Phase fault I> 0.08 – 3.2In 0.01InI>> 0.08 – 32In 0.01InI>>> 0.08 – 32In 0.01InI< 0.02 – 3.2In 0.01In

Standard earth fault Io> 0.005 – 0.8In 0.0025InIo>> 0.005 – 8.0In 0.0025InIo>>> 0.005 – 8.0In 0.0025InIo< 0.005 – 0.8In 0.0025In

Special earth fault Io> 0.02 – 32In 0.01InIo>> 0.02 – 32In 0.01InIo>>> 0.02 – 32In 0.01InIo< 0.02 – 3.2In 0.01In

Sensitive earth fault Io> 0.001 – 0.16In 0.0005InIo>> 0.001 – 1.6In 0.0005InIo>>> 0.001 – 1.6In 0.0005InIo< 0.0005 – 0.16In 0.0005In

Reset General 0.95Is

3.2 Dual powered relays

Threshold (Is) Step size

Phase fault I> 0.4 – 2.4In 0.01InI>> 0.4 – 32In 0.01InI>>> 0.4 – 32In 0.01InI< 0.02 – 2.4In 0.01In

Standard earth fault Io> 0.005 – 0.6In 0.0025InIo>> 0.005 – 8.0In 0.0025InIo>>> 0.005 – 8.0In 0.0025InIo< 0.005 – 0.6In 0.0025In

Special earth fault Io> 0.02 – 2.4In 0.01InIo>> 0.02 – 32In 0.01InIo>>> 0.02 – 32In 0.01InIo< 0.02 – 2.4In 0.01In


Sensitive earth fault Io> 0.001 – 0.16In 0.0005InIo>> 0.001 – 1.6In 0.0005InIo>>> 0.001 – 1.6In 0.0005InIo< 0.0005 – 0.16In 0.0005In

Reset General 0.95Is

The sensitive earth fault settings are only available on KCEU 142/242 andsensitive versions of KCEG 112/152 relays

Note: Operation is not guaranteed for earth faults below 0.2In, regardless of theactual setting, when the load current is below 0.4In and the auxiliaryvoltage is not available. See also the special application notes for dualpowered relays and the table in Chapter 4, Section13.3 regarding themaximum number of outputs and inputs that may be energized at any onetime.

Section 4. TIME SETTING RANGES

4.1 Inverse definite minimum time (IDMT)

Nine inverse reset time characteristics are available and the general mathematicalexpression for the curves is:

t = TMS secondsk

Ð1IIs

a + c

where TMS = Time Multiplier (0.025 to 1.5 in 0.025 steps)I = Fault currentIs = Overcurrent settingk, c, a = Constants specifying curve

Curve No. Description Name IEC Curve k c a

0 Definite Time DT – 0 0 to 100 11 Standard Inverse SI30xDT A 0.14 0 0.022 Very Inverse VI30xDT B 13.5 0 13 Extremely Inverse EI10xDT C 80 0 24 Long Time Inverse LTI30xDT – 120 0 15 Moderately Inverse MI D 0.103 0.228 0.026 Very Inverse VI E 39.22 0.982 27 Extremely Inverse EI F 56.4 0.243 28 Short Time Inverse STI30xDT – 0.05 0 0.049 Rectifier Protection RECT – 45900 0 5.6

Although the curves tend to infinity at the setting current value (Is), the guaranteedminimum operation current is 1.05Is ±0.05Is for all inverse characteristic curves,except curve 10 for which the minimum operating current is 1.6Is ±0.05Is(see section on rectifier protection).


Curves numbers 1, 2, 4, and 8 become definite time for currents in excess of30xIs. Curve 3 becomes definite time for currents above 10xIs to give extra timegrading steps at high current levels. Curves 1, 2 and 3 are curves A, B and C inIEC 60255-3.

Curves 5, 6 and 7 are slightly different in that they tend to a definite operatingtime given by the constant (a) at high fault levels. Curves 5, 6 and 7 wereproposed by IEEE/ANSI, for inclusion in the IEC standard IEC 60255-3, as curvesD, E and F.

4.2 Definite independent time

Setting range Step size

to>/t> Definite time 0 to 100s 0.01stRESET Definite time 0 to 60s 0.1sto>>/t>> Definite time 0 to 100s 0.01sto>>>/t>>> Definite time 0 to 10s 0.01s

4.3 Auxiliary time delays

Setting range Step size

tV< Definite time 0 to 10s 0.01stAUX1 Definite time 0 to 28 days 0.01s min – gradedtAUX2 Definite time 0 to 28 days 0.01s min – gradedtAUX3 Definite time 0 to 28 days 0.01s min – gradedtBF Definite time 0 to 10s 0.01stTRIP Definite time 0.5 to 5s 0.1stCLOSE Definite time 0.5 to 5s 0.1s

Section 5. OTHER PROTECTION SETTINGS

5.1 Directional

Characteristic angle (Øc) –180°.....0°.....+180°

Operating boundary Øc ±90° (±85° for wattmetric)

Voltage threshold Vp> 0.6V for Vn = 110V2.4V for Vn = 440V

Voltage threshold Vop> 0.6V to 80V – step 0.2V for Vn = 110V2.4V to 320V – step 0.8V for Vn = 440V

Additional settings for KCEU 142/242 relays

Po> (1A) 0 – 20W 50mW steps

Po> (2A) 0 – 100W 250mW steps

5.2 Thermal

Time Constant 1 to 120 minutes – step 1 minute

Current Rating Ith> 0.08In to 3.2In – step 0.01In

Thermal alarm level th> 0 – 110% of Ith> 1% of Ith> steps


5.3 Undervoltage

Undervoltage (V<) 0 to 220V for Vn = 110V0 to 880V for Vn = 440V

5.4 Underfrequency

Under frequency (F<) 46 to 64Hz step 0.01Hz

Reset F<+0.05Hz

Underfrequency function is not available on KCEU 142/242 relays

5.5 Ratios

CT ratios 9999 : 1 Default = 1 : 1

VT ratios 9999 : 1 Default = 1 : 1

Section 6. MEASUREMENT (DISPLAYED)

Voltage (0 – 327) x VT ratio volts phase/neutral

Current (0 – 64)In x CT ratio amps per phase

Power (0 – 9.999)x1021 W

VAr (0 – 9.999)x1021 VAr

VA (0 – 9.999)x1021 VA

CB Operations (0 – 65535)

Current2 broken (0 – 9.999)x1021 A2 (or A)

Frequency 45 – 65 (or 0 ) Hz

Section 7. ACCURACY

7.1 Reference conditions

Ambient temperature 20°C

Frequency 50Hz or 60Hz (whichever is set)

Time multiplier setting 1.0

Auxiliary voltage 24V to 125V (auxiliary powered)48V to 250V (auxiliary powered)100V to 250V (dual powered)

Fault Position Within ±80 ° of the RCA where appropriate.

7.2 Current

Undercurrent Minimum operation ±10% (> 4 x minimum setting)±20% (< 4 x minimum setting)

Overcurrent Minimum operation ±5%Reset ±5%Repeatability ±2.5%


Earth Fault Minimum operation ±20% (@ minimum setting)±10% (@2x minimum setting)±5% (@ >4x minimum setting)

7.3 Time delays

Referencerange

Operating time IDMT except (EI) ±5% + (20 to 40)ms 2Is to 30Isand (Rectifier)

(t>/to>) Extremely inv (EI) ±7.5% + (20 to 40)ms 2Is to 10IsRectifier ±7.5% + (20 to 40)ms 2Is to 5IsDefinite time ±0.5% + (20 to 40)ms 3Is to 30Is

Repeatability Inverse time ±2% ±40msDefinite time ±0.5% or10ms

Overshoot time Less than 50ms when current reduced to zero.Reset time Definite time ±1% ±50mst>/to>

Disengagement I< typically 35msI>/Io> typically 30mst>/to> typically 30ms*t>>/to>> typically 50ms*t>>>/to>>> typically 50ms*

*Minimum dwell disengagement time is affected if measuring circuit resetswithin 100ms of pick-up. For further information see Chapter 3,Section 5.6.

7.4 Directional

Characteristic angle Øc ±2°

Operating boundary Øc ±90° accuracy ±2°

PU – DO differential less than 3° (typically <1°)

Polarizing voltage (Vp>) ±10% (at Øc ±80°)

Polarizing voltage (Vop>) ±10% (at Øc ±80°)

Wattmetric characteristic ±4% (typical)

7.5 Thermal

Thermal (Ith>) Minimum operation ±5%

Operation Time ±2% of TC from 1.2Ith> to 5Ith>

7.6 Undervoltage

Undervoltage (V<) ±10%

Undervoltage delay (tV<) ±0.5%+(20 to 70)ms

7.7 Under frequency

Under frequency (F<) ±0.02Hz from 46Hz to 64Hz


7.8 Auxiliary timers

Operating time Set time ±0.5%(set time)+(15 to 35)ms

Disengagement time 0 to 10ms (for timers alone)

15 to 30ms (including output relays and opto-inputs)

Breaker Fail Timer tBF ±0.5% or ±10ms

7.9 Measurements

Voltage ±2%Vn (typical) – Reference range = 1 to 320 V

Current ±2%In (typical) – Reference range = setting range

Power ±2%Pn (typical)

VAr ±2%Pn (typical)

VA ±2%Pn (typical)

Frequency (45 – 65Hz) ±0.02Hz (typical)

Section 8. INFLUENCING QUANTITIES

8.1 Ambient temperature

Operative range –25°C to +55°C

Current settings ±1%

Voltage settings ±0.03% per °C

Operation times ±1%

Angle measurement <2°

8.2 Frequency

8.2.1 With frequency tracking

Operative range 46 to 65Hz (47 to 52Hz for KCEU relays)

Current setting ±1%

Voltage settings ±1%

Operating times ±1%


8.2.2 Without frequency tracking (KCGG 122 KCEG 112)

Reference range 47 to 52Hz or 57 to 61Hz

Current settings ±2%

Operating times ±2%



8.3 Auxiliary supply

Nominal Operative range

24/125V 19 to 150V dc (aux powered)50 to 133V ac (aux powered)

48/250V 33 to 300V dc (aux powered)87 to 265V ac (aux powered)

100/250V 60 to 300V dc (dual powered)60 to 265V ac (dual powered)

Current settings ±0.5%Voltage settings ±0.5%Operation times ±0.5%Angle measurement ±0.5°

8.4 System X/R

Transient overreach <5%

Effect upon directional characteristics

Effect upon Operating Times (fault 45° from RCA)<40ms (X/R < 30, I ≥5Is)<75ms (X/R ≤90, I ≥5Is)

Minimum protection time delay for directional stability (fault 45° from RCA)40ms (X/R ≤15, I ≤40In)

Additional time delay incurred for forward direction fault (45° from RCA)≤60ms (X/R ≤5, I <16In)≤100ms (X/R ≤15, I <40In)

Section 9. OPTO-ISOLATED INPUTS

Capture time 12.5 ±2.5ms at 50Hz

10.4 ±2.1ms at 60Hz

Release time 12.5 ±2.5ms at 50Hz10.4 ±2.1ms at 60Hz

Minimum operating voltage >35V dc

Maximum operating voltage 50Vdc

Input resistance 10kΩ(add 12kW for every additional 50V inexcess of 50V)

Maximum series lead resistance 2kΩ for single input at 40V min.1kΩ for 2 inputs in parallel at 40V min.0.5kΩ for 4 inputs in parallel at 40V min.

Maximum ac induced loop voltage 50V rms (thermal limit)

Maximum capacitance coupledac voltage 250V rms via 0.1µF


Section 10. OUTPUT RELAYS

10.1 Output relays 0 to 7

Type 1 make

Rating Make 30A and carry for 0.2s

Carry 5A continuous

Break DC – 50W resistive25W inductive (L/R = 0.04s)

AC – 1250VA (maxima of 5A)Subject to maxima of 5A and 300V

10.2 Watchdog

Type 1 make + 1 break

Rating Make 10A and carry for 0.2s

Carry 5A continuous

Break DC – 30W resistiveDC – 15W inductive (L/R = 0.04s)AC – 1250VA (maxima of 5A)Subject to a maxima of 5A and 300V

Durability >10,000 operations

Section 11. OPERATION INDICATOR

3 light emitting diodes – internally powered.

16 character by 2 line liquid crystal display (with backlight).

Section 12. COMMUNICATION PORT

Language Courier

Transmission Synchronous – RS485 voltage levels

Format HDLC

Baud Rate 64kbit/s

K-Bus Cable Screened twisted pair

Length 1000m

Bus Loading 32 units (mulitdrop system)

Section 13. CURRENT TRANSFORMER REQUIREMENTS

CT requirements for use in typical applications are shown below. These CTrequirements are based on a maximum prospective fault current of 50x relay ratedcurrent (In) and the relay having a maximum high-set setting of 25In. The CTrequirements are designed to provide operation of the phase and earth faultelements.


Where the criteria for a specific application are in excess of those detailed above,or the actual lead resistance exceeds the limiting value quoted, the CTrequirements may need to be increased. CT requirements for a variety of furtherapplications are provided in publication R6096.

Auxiliary powered relays – KCGG 122, 142 and KCEG 112, 142,152 and KCEU 142

Relay and CT Nominal Accuracy Accuracy Limiting leadsecondary rating output class limit factor resistance

(one way)

1A 2.5VA 10P 20 0.6Ω

5A 7.5VA 10P 20 0.06Ω

Dual powered relays – KCEG 242 and KCEU 242

Relay and CT Nominal Accuracy Accuracy Limiting leadsecondary rating output class limit factor resistance

(one way)

1A 7.5VA 10P 15 0.7Ω

5A 10VA 10P 20 0.06Ω

Core balance current transformer requirements for earth faults

Core balance CTs of metering class accuracy are required and should have aknee-point voltage satisfying the following formulae. (The value of current used forIfn should be the maximum possible earth fault current that may flow). In addition,it should be ensured that the phase error of the applied CT is less than 90' at 10%of rated current and less than 150' at 1% of rated current.

For the IDMT characteristic of the first element, Io>:

Vk > (Icn/2).(Rct + Rwp + Rwn + Rrp + Rrn) earth faults

Vk > (Ifn/2).(Rct + Rwp + Rwn + Rrp + Rrn) earth faults

where: Vk = Required CT knee-point voltage

Icn = Maximum prospective secondary current for earth faults or31 times Io> setting (whichever is lower)

Ifn = Maximum prospective secondary current for earth faults

Rct = CT secondary winding resistance

Rwp = Resistance of each CT phase lead

Rwn = Resistance of each CT neutral lead

Rrp = Impedance of relay phase current input

Rrn = Impedance of relay neutral current input

Where the K Range relays are being used for restricted earth fault protection theCTs must be sized to assure stability as described in Chapter 4, Section 5.10.

The accuracy class of the CTs should be chosen to suit the required accuracy ofmeasurement values.


Limits of error for accuracy classes 5P and 10P

Accuracy class Current error (%) Composite error (%)

5P ±1 ±5

10P ±3 ±10

The accuracy limit factors detailed above should be used to ensure full range faultrecording.

Section 14. HIGH VOLTAGE WITHSTAND

14.1 Dielectric withstand IEC 60255-5: 1977

2.0kV rms for one minute between all terminals and case earth, except terminal 1.2.0kV rms for one minute between terminals of independent circuits, includingcontact circuits.

1.5kV rms for 1 minute across open contacts of output relays 0 to 7.

1.0kV rms for 1 minute across open contacts of the watchdog relay.

14.2 High voltage impulse IEC 60255-5: 1977

5kV peak, 1.2/50µs, 0.5J between all terminals and all terminals to case earth.

14.3 Insulation resistance IEC 60255-5: 1977

>100MW when measured at 500Vdc

14.4 High frequency disturbance IEC 60255-22-1: 1988

Class III

2.5kV peak between independent circuits and case.

1.0kV peak across terminals of the same circuit.

14.5 Fast transient IEC 60255-22-4: 1992

Class IV

4kV, 2.5kHz applied to all inputs and outputs.

14.6 EMC compliance

89/336/EEC

Compliance to the European Commission Directive on EMC is claimed via theTechnical Construction File route.

EN 50081-1EN 50082-2

Generic Standards are used to establish conformity.

14.7 Electrostatic discharge test IEC 60255-22-2: 1996

Class 3 (8kV) discharge in air with cover in place

Class 2 (4kV) point contact discharge with cover removed


Section 15. IEEE/ANSI SPECIFICATIONS

15.1 Standard for relay systems associated with electrical powerapparatus

C37.90 - 1989

15.2 Surge withstand capability

C37.90.1 - 1989

15.3 Radio electromagnetic interference

C39.90.2 - 1989

Section 16. ENVIRONMENTAL

16.1 Temperature IEC 60255-6: 1988

Storage and transit –25°C to +70°C

Operating –25°C to +55°C

16.2 Humidity IEC 60068-2-3: 1969

56 days at 93% relative humidity and 40°C

16.3 Enclosure protection IEC 60529:1989

IP50 (Dust protected)

16.4 Vibration IEC 60255-21-1:1988

Class 1

16.5 Shock and bump IEC 60255-21 2:1988

Class 1

16.6 Seismic IEC 60255-21-3:1993

Class 1


Section 17. MODEL NUMBERS

Relay type: K C E G 0 1

112 1 1 2142 1 4 2152 1 5 2242 2 4 2

Configuration:Standard 0 1

Case size:Size 4 Midos flush mounting (KCEG112 only) DSize 6 Midos flush mounting (KCEG142/152 only) FSize 8 Midos flush mounting (KCEG242 only) H

Auxiliary voltage:24/125V (except KCEG242) 248/250V (except KCEG242) 5110/250V (KCEG242 only) 9

Operating voltage:110V ac; 50-60Hz 1440V ac; 50-60Hz 4

CT rating:1A CT standard (0.005In to 0.8In for earth faults) (0.005In to 0.6In for earth faults) C1A CT special (0.02In to 3.2In for earth faults) (0.002In to 2.4In for earth faults) D5A CT standard (0.005In to 0.8In for earth faults) (0.005In to 0.6In for earth faults) E5A CT special (0.02In to 3.2In for earth faults) (0.02In to 2.4In for earth faults) F

Language:English EFrench FGerman GSpanish S

Relay type: K C G G 0 1 D 0

122 1 2 2142 1 4 2

Configuration:Standard 0 1Customer Settings (standard only) X XReduced input/output 0 2Customer settings (reduced I/O) X Y

Case size:Size 4 Midos flush mounting D

Auxiliary voltage:24/125V 248/250V 5

Not used

CT rating:1A CT standard (0.005In to 0.8In for earth faults) C1A CT special (0.02In to 3.2In for earth faults) D5A CT standard (0.005In to 0.8In for earth faults) E5A CT special (0.02In to 3.2In for earth faults) F



Relay type: K C E U 0 1

142 1 4 2242 2 4 2

Configuration:Standard 0 1

Case size:Size 6 Midos flush mounting (KCEU 142 only) FSize 8 Midos flush mounting (KCEU 242 only) H

Auxiliary voltage:24/125V (except KCEU242) 248/250V (except KCEU242) 5110/250V (KCEU242 only) 9

Operating voltage:110V ac; 50-60Hz 1440V ac; 50-60Hz 4

CT rating:1A CT standard (0.005In to 0.8In for earth faults) (0.005In to 0.6In for earth faults) C1A CT special (0.02In to 3.2In for earth faults) (0.002In to 2.4In for earth faults) D5A CT standard (0.005In to 0.8In for earth faults) (0.005In to 0.6In for earth faults) E5A CT special (0.02In to 3.2In for earth faults) (0.02In to 2.4In for earth faults) F



Section 18. FREQUENCY RESPONSE

The operating criteria for each element have been chosen to suit the applicationsfor which it is most likely to be used. Knowing how these elements respond underoperating conditions will help to apply them effectively.

Figure 1: Response of Fourier filtering

Measurement is based on the Fourier derived value of the fundamental componentof current and Figure 1 shows the frequency response that results from this filtering.The '1' on the horizontal scale relates to the selected rated frequency of the relayand the figures '2', '3', '4' etc. are the second, third and fourth harmonicfrequencies respectively. It can be seen that harmonics up to and including the 6thare suppressed, giving no output. The 7th is the first predominant harmonic andthis is attenuated to approximately 30% by the anti-aliasing filter. For powerfrequencies that are not equal to the selected rated frequency. ie. the frequencydoes not coincide with '1' on the horizontal scale, the harmonics will not be ofzero amplitude. For small frequency deviations of ±1Hz, this is not a problem butto allow for larger deviations, an improvement is obtained by the addition offrequency tracking.

With frequency tracking the sampling rate of the analogue/digital conversion isautomatically adjusted to match the applied signal. In the absence of a signal ofsuitable amplitude to track, the sample rate defaults to that to suit the selected ratedfrequency (Fn) for the relay. In presence of a signal within the tracking range(45 to 65Hz), the relay will lock on to the signal and the '1' on the horizontal axisin diagram above will coincide with the measured frequency of the measuredsignal. The resulting output for 2nd, 3rd, 4th, 5th and 6th harmonics will be zero.Thus this diagram applies when the relay is not frequency tracking the signal andalso if it is tracking a frequency within the range 45 to 65Hz.

Power frequency signals are predominant in phase quantities and are thereforeused in the frequency tracking routine, whereas, earth fault quantities often containa high proportion of harmonic signals. The earth fault element of multi-pole relayswill generally be locked to the power frequency as the relay tracks it using thephase quantities. If the relay were to track a frequency above 65Hz then it wouldtry to lock on to a sub-harmonic frequency and the response would then be asshown in diagram below. The horizontal axis of this graph is in Hz, the unit of

Fourier filter response

Anti-aliasing filter response

Harmonic

1

1 2 3 4 5 6 7 80


frequency, and a substantial output is produced for the 2nd harmonic of the systemfrequency and also for the 3rd, etc. Hence it is for this reason the relays arerestricted to tracking the phase quantities and do not track earth fault signals.

Figure 2: Response when frequency tracking

18.1 Transient overreach

The I>>/Io>> and I>>>/Io>>> elements are often required for instantaneous highset and/or low set functions and for these applications they need to be unaffectedby offset waveforms, which may contain a large dc exponential component, andby transformer inrush currents. To achieve this, two criteria for operation areapplied independently. The first is that the Fourier derived power frequencycomponent of the fault current is above the set threshold, as for I>/Io>. Thesecond is that the peak of any half cycle of current exceeds twice the set thresholdvalue and is provided to reduce the operation time to less than that which could beobtained with the Fourier measurement alone.

18.2 Peak measurement

Another point to be aware of is that the second criterion uses peak values andthese are only filtered by the anti-aliasing filter. However, the peak measurementsare still based on sampled values and the position of the samples relative to thepeak of the harmonic will depend on the phase relationship. The frequencyresponse will therefore be modified for the I>>/Io>> and I>>>/Io>>> elementsfor which the diagram below is typical only.

For certain applications it may be necessary to set the I>> or Io>> element to alow setting, possibly lower than that for the I> or Io> elements. In these situationsthe modified frequency response shown may not be acceptable because of thelack of harmonic rejection. To overcome this problem a software link is provided toselect or deselect the peak detection feature for the I>> and Io>> overcurrentelements.

The peak measurement is not used for the I>>/Io>> and I>>>/Io>>> elements ofdirectional overcurrent relays. This is to ensure that the overcurrent and directionalmeasurement is made from the same data to ensure decisive operation. Therefore,the following diagram will apply to KCEG/KCEU relays and a KCGG relay thathas been set so as not to respond to peak values.

1

0 100 200 300 400Frequency - Hz


1

0 100 200 300 40050Frequency Hz

Filter response for I>>/I>>> with peak measurementtracking a single frequency

Figure 3: Frequency response when relay responds to both peak and Fourier values

18.3 Frequency response of directional elements

The phase directional elements are provided with synchronous polarization whichis maintained for 320ms, or 3.2s, after the voltage collapses so that decisiveoperation is ensured. During the period of synchronous polarization the relaytracks the frequency on a current signal so that the phase correction is maintained,even with some deviation in frequency.



Relays

Service Manual

Chapter 8Commissioning


1. INTRODUCTION 12. PRODUCT SETTING FAMILIARISATION 13. EQUIPMENT REQUIRED FOR TESTING 33.1 Minimum equipment required for KCGG relays 33.2 Additional equipment required for KCEG and KCEU relays 33.3 Optional equipment 34. PRODUCT VERIFICATION TESTS 34.1 With the relay de-energised 44.1.1 Visual inspection 44.1.2 Insulation 54.1.3 External wiring 54.1.4 Watchdog contacts 54.1.5 Auxiliary supply 64.2 With the relay energised 64.2.1 Watchdog contacts 64.2.2 Light emitting diodes (LEDs) 64.2.3 Liquid crystal display (LCD) 74.2.4 Field supply 74.2.5 Capacitor trip voltage (KCEG 242 and KCEU 242 relays only) 74.2.6 Input opto-isolators 74.2.7 Output relays 84.2.8 Communications ports 94.2.9 Current inputs 94.2.10 Voltage inputs (KCEG and KCEU relays only) 104.2.11 Energisation from line current transformers

(KCEG 242 and KCEU 242 only) 105. SETTING TESTS 115.1 Apply customer settings 115.2 Ckeck settings 115.3 Demonstrate correct relay operation 115.3.1 Non-directional phase fault test (KCGG 122/142 relays) 115.3.1.1 Connect the test circuit 115.3.1.2 Perform the test 125.3.1.3 Check the operating time 125.3.2 Directional phase fault test (KCEG 142/242 and KCEU 142/242 relays) 125.3.2.1 Connect the test circuit 125.3.2.2 Perform boundary of operation test 135.3.2.3 Perform the timing test 145.3.3 Directional earth fault function test (KCEG 112/152 relays) 145.3.3.1 Connect the test circuit 145.3.3.2 Perform boundary of operation test 145.3.3.3 Perform the timing test 15


6. ON-LOAD CHECKS 156.1 Check current and voltage transformer connections

(KCEG and KCEU relays) 156.1.1 Voltage connections 156.1.2 Current connections 166.2 Check current transformer connections (KCGG relays) 167. FINAL CHECKS 178. PROBLEM SOLVING 188.1 Password lost or not accepted 188.2 Protection settings 188.2.1 Settings for high sets not displayed 188.2.2 Second setting group not displayed 188.2.3 Function links can not be changed 188.2.4 Curve selection can not be changed 188.3 Alarms 198.3.1 Watchdog alarm 198.3.2 Cell [0022 Alarms] link 0 = ‘1’ 198.3.3 Cell [0022 Alarms] link 1 = ‘1’ 198.3.4 Cell [0022 Alarms] link 2 = ‘1’ 208.3.5 Cell [0022 Alarms] link 3 = ‘1’ 208.3.6 Cell [0022 Alarms] link 4 = ‘1’ 208.3.7 Cell [0022 Alarms] link 5 = ‘1’ 208.3.8 Cell [0022 Alarms] link 7 = ‘1’ 208.3.9 Fault flags will not reset 208.4 Records 208.4.1 Problems with event records 208.4.2 Problems with disturbance records 218.5 Circuit breaker maintenance records 228.6 Communications 228.6.1 Measured values do not change 228.6.2 Relay no longer responding 228.6.3 No response to remote control commands 228.7 Output relays remain picked up 238.8 Thermal state 238.8.1 Thermal state reset to zero 238.8.2 Thermal ammeter time constants 23


9. MAINTENANCE 239.1 Remote testing 239.2 Maintenance checks 24921 Remote testing 249.2.1.1 Alarms 249.2.1.2 Measurement accuracy 249.2.1.3 Trip test 249.2.1.4 Circuit breaker maintenance 259.2.2 Local testing 259.2.2.1 Alarms 259.2.2.2 Measurement accuracy 259.2.2.3 Trip test 259.2.2.4 Circuit breaker maintenance 259.2.2.5 Additional tests 259.3 Method of repair 269.3.1 Replacing a PCB 269.3.1.1 Replacement of user interface 269.3.1.2 Replacement of main processor board 269.3.1.3 Replacement of auxiliary expansion board 269.3.2 Replacing output relays 279.3.3 Replacing the power supply board 279.3.4 Replacing the back plane (size 4 and 6 cases) 279.4 Recalibration 27

Figure 1: Connections for directional phase fault tests 13Figure 2: Connections for directional earth fault tests 14


Section 1. INTRODUCTION

The KCEG, KCGG and KCEU relays are fully numerical in their design,implementing all protection and non-protection functions in software. The relaysemploy a high degree of self-checking and, in the unlikely event of a failure, willgive an alarm. As a result of this, the commissioning tests do not need to be asthorough as with non-numeric electronic or electro-mechanical relays.

To commission numeric relays it is only necessary to verify that the hardware isfunctioning correctly and the application-specific software settings have beenapplied to the relay. It is considered unnecessary to test every function of the relayif the settings have been verified by one of the following methods:

• Extracting the settings applied to the relay using appropriate setting software(Preferred method)

• Via the operator interface.

To confirm that the product is operating correctly once the customer’s settings havebeen applied, a test should be performed on a single element.

Unless previously agreed to the contrary, the customer will be responsible fordetermining the application-specific settings to be applied and testing scheme logicapplied by external customer wiring.

Blank commissioning test and setting records are provided in Appendix 4 forcompletion as required.

Before carrying out any work on the equipment, the user should befamiliar with the contents of the ‘Safety Section’ and Chapter 2,‘Handling and Installation’ of this manual.

Section 2. PRODUCT SETTING FAMILIARISATION

When commissioning a KCEG, KCGG or KCEU relay for the first time, sufficienttime should be allowed to become familiar with the method by which settings areapplied.

Chapter 3, Section 3 contains a detailed description of the menu structure of theKCEG, KCGG and KCEU relays but the key functions are summarised in Table 1.

With the cover in place only the [F] and [0] keys are accessible. Data can only beread or flag and counter functions reset. No protection or configuration settingscan be changed.

Removing the cover allows access to the [+] and [–] keys so that all settings can bechanged and there is greater mobility around the menu.

In Table 1, [F] long indicates that the key is pressed for at least 1 second and[F] short for less than 0.5 second. This allows the same key to perform more thanone function.

Alternatively, if a portable PC is available together with a K-Bus interface andsuitable setting software, the menu can be viewed a page at a time to display afull column of data and text. Settings are also more easily entered and the finalsettings can be saved to a file on a disk for future reference or printing apermanent record. Refer to the software user manual for details and allow sufficienttime to become familiar with its operation if it is being used for the first time.


Current Display Key Press Effect of Action

Default display [F] short or Display changes to menu column heading[F] long “SYSTEM DATA”.

[+] † Backlight turns ON – no other effect.

[–] † Backlight turns ON – no other effect.

[0] short Steps through the available default displays.

[0] long Backlight turns ON – no other effect.

Flag faults after [F] short or Display moves to menu column headinga trip [F] long “SYSTEM DATA”.

[+] † Backlight turns ON – no other effect.

[–] † Backlight turns ON – no other effect.

[0] short Backlight turns ON – no other effect.

[0] long Resets trip LED and returns to default display.

Column heading [F] short Move to next item in menu column.

[F] long Move to next column heading.

[+] † Move to previous column heading.

[–] † Move to next column heading.


[0] long Re-establishes password protection and returns todefault display.

Any menu cell [F] short Move to next item in menu column.

[F] + [0] Move to previous item in menu column.

[F] long Move to next column heading.


[0] long Resets the value if cell is resettable.

A settable cell † [+] or [–] Puts relay in the setting mode (flashing cursor onbottom line of display). The password must first beentered for protected cells.

Setting mode † [F] Changes to the confirmation display.If function links, relay or input masks are displayed,the [F] key will step through them from left to rightand finally changing to the confirmation display.

[+] Increments value – rapidly increases if held depressed.

[–] Decrements value – rapidly decreases if held depressed.

[0] Escapes from the setting mode without the settingbeing changed.

Confirmation [+] Confirms setting and enters the new value.mode † [–] Returns prospective value of setting for checking

and further modification.

[0] Escapes from the setting mode without a setting change.

† Only available with front cover removed

Table 1: Functions of keys


Section 3. EQUIPMENT REQUIRED for COMMISSIONING

3.1 Minimum equipment required for KCGG relays

Overcurrent test set with interval timer.

Multimeter with suitable ac and dc voltage, and ac current, ranges.

Audible continuity tester (if not included in multimeter).

3.2 Additional equipment required for KCEG and KCEU relays

Phase-shifting transformer

Variable transformer (Variac) and resistors (if overcurrent test can not change thephase angle between current and voltage).

Phase angle meter.

Phase rotation meter (not required for the KCEG 112).

3.3 Optional equipment

Multi-finger test plug type MMLB01 (if test block type MMLG installed).

A portable PC, with appropriate software and a KITZ 101 K-Bus/IEC60870-5interface unit (if one is not already installed at site) will be useful and saveconsiderable time. However, it is not essential to commissioning.

A printer (for printing a setting record from the portable PC).

Section 4. PRODUCT CHECKS

These product checks cover all aspects of the relay that need to be checked toensure that it has not been physically damaged prior to commissioning, isfunctioning correctly and all measurements are within the stated tolerances.

If the application-specific settings have been applied to the relay prior tocommissioning, it is advisable to make a copy of the settings so as to allow theirrestoration later. This can be done by:

• Obtaining a setting file on a diskette from the customer (this requires a portablePC with appropriate software for downloading the settings to the relay.)

• Extracting the settings from the product itself (this again requires a portable PCwith appropriate software.)

• Manually creating a setting record. This could be done using a copy of thesetting record located in Appendix 4.

If the customer has changed the password preventing unauthorised changes tosome of the settings, either the revised password should be provided or thecustomer should restore the original password prior to commencement of testing.

Note: In the event that the password has been lost, a recovery password can beobtained from ALSTOM T&D Protection & Control Ltd by quoting the modeland serial numbers of the particular relay. The recovery password is uniqueto that relay and will not work on any other relay.


4.1 With the relay de-energised

The following group of tests should be carried out without the auxiliary supply ormeasured voltages being applied to the relay and the trip circuit isolated.

If an MMLG test block is provided, this can easily be achieved by inserting testplug type MMLB01 which effectively open-circuits all wiring routed through the testblock.

Before inserting the test plug, reference should be made to the scheme diagram toensure that this will not potentially cause damage or a safety hazard.For example, the test block may also be associated with protection currenttransformer circuits. It is essential that the sockets in the test plug, which correspondto the current transformer secondary windings, are linked before the test plug isinserted into the test block.

DANGER: Never open circuit the secondary circuit of a currenttransformer since the high voltage produced may belethal and could damage insulation.

If an MMLG test block is not provided, the voltage transformer supply to the relayshould be isolated by means of the panel links or connecting blocks. The linecurrent transformers should be short-circuited and disconnected from the relayterminals. Where means of isolating the auxiliary supply and trip circuit(eg. isolation links, fuses, MCB etc.) are provided, these should be used. If this isnot possible, the wiring to these circuits will have to be disconnected and theexposed ends suitably terminated to prevent them being a safety hazard.

4.1.1 Visual inspection

Loosen the cover screws and remove the cover. The relay module can now bewithdrawn from its case. In accordance with Chapter 2, Section 2 (Handling ofElectronic Equipment), carefully examine the module and case to see that nodamage has occurred since installation.

Check that the serial and model numbers on the front plate and label on theleft-hand, inside face of the case are identical. The only time that the serialnumbers may not match is when a failed relay has been replaced to providecontinuity of protection.

The rating information on the front of the relay should also be checked to ensure itis correct for the particular installation.

Visually check that the current transformer shorting switches, fitted on the terminalblock inside the rear of the case, are wired into the correct circuit. The shortingswitches are between terminals 21 and 22, 23 and 24, 25 and 26, and 27 and28 for all versions of KCEG, KCGG and KCEU. Ensure that, while the relaymodule is withdrawn, the shorting switches are closed by checking with acontinuity tester.

Ensure that the case earthing connection, above the rear terminal block, is used toconnect the relay to a local earth bar. Where there is more than one relay in a tier,it is recommended that a copper earth bar should be fitted connecting the earthterminals of each case in the same tier together. However, as long as an adequateearth connection is made between relays, the use of a copper earth bar is notessential.


4.1.2 Insulation

Insulation resistance tests only need to be done during commissioning if thecustomer requires them to be done and if they have not been performed duringinstallation.

If insulation resistance tests are required, isolate the relay trip contacts and re-insertthe relay module.

Isolate all wiring from the earth and test the insulation with an electronic orbrushless insulation tester at a dc voltage not exceeding 500V and internalimpedance greater than 100Mý. Terminals of the same circuits should betemporarily strapped together.

The main groups of relay terminals are:

a) Voltage transformer circuitsb) Current transformer circuitsc) Auxiliary voltage supplyd) Field voltage output and opto-isolated control inputse) Relay contactsf) Communication portg) Case earth

On completion of the insulation resistance tests, ensure all external wiring iscorrectly reconnected to the unit.

4.1.3 External wiring

Check that the external wiring is correct to the relevant relay diagram or schemediagram. The relay diagram number appears on a label on the left-hand, insideface of the case and the corresponding connection diagram can be found inAppendix 3 of this manual. If a connection diagram from the service manual isused, the customer’s mask allocations for the input opto-isolators and output relaysshould be checked to see which functions have been configured in each mask.

If an MMLG test block is provided, the connections should be checked against thescheme diagram. It is recommended that the supply connections are to the live sideof the test block (coloured orange with the odd numbered terminals (1, 3, 5, 7etc.)). The auxiliary supply is normally routed via terminals 13 (supply positive) and15 (supply negative), with terminals 14 and 16 connected to the relays positiveand negative auxiliary supply terminals respectively. However, check the wiringagainst the schematic diagram for the installation to ensure compliance with thecustomer’s normal practice.

4.1.4 Watchdog contacts

If not already done to perform the insulation resistance tests, isolate the relay tripcontacts and re-insert the relay module. Using a continuity tester, check thewatchdog contacts are in the states given in Table 2 for a de-energised relay.

Terminals Contact stateRelay de-energised Relay energised

3 and 5 Closed Open4 and 6 Open Closed

Table 2: Watchdog contact status


4.1.5 Auxiliary supply

The relay can be operated from either an ac or a dc auxiliary supply but theincoming voltage must be within the operating ranges specified in Table 3.

Without energising the relay, measure the auxiliary supply to ensure it is within theoperating range.

Relay DC operating AC operating Maximum crestrating (V) range (V) range (V) voltage (V)24/125 19 – 150 50 – 133 19048/250 33 – 300 87 – 265 380

Table 3: Operational range of auxiliary supply

It should be noted that the relay can withstand an ac ripple of up to 12% of theupper rated voltage on the dc auxiliary supply. However, in all cases the peakvalue of the auxiliary supply must not exceed the maximum crest voltage. Do notenergise the relay using the battery charger with the battery disconnected as thiscan seriously damage the relays power supply circuitry.

Energise the relay if the auxiliary supply is within the operating range. If an MMLGtest block is provided, it may be necessary to link across the front of the test plug torestore the auxiliary supply to the relay.

4.2 With the relay energised

The following group of tests verify that the relay hardware and software isfunctioning correctly and should be carried out with the auxiliary supply applied tothe relay.

The measured currents and voltages must not be applied to the relay for thesechecks.


Using a continuity tester, check the watchdog contacts are in the states given inTable 2 for an energised relay.

Note: This test can not be performed with dual powered relays because theirwatchdog contacts work in a different way to those of an auxiliary poweredrelay (ie. they do not give an alarm when the supply fails and only pick-upwhen the relay is not healthy).

4.2.2 Light emitting diodes (LEDs)

On power up the green LED should have illuminated and stayed on indicating therelay is healthy. The relay has non-volatile memory which remembers the state (onor off) of the yellow alarm and red trip LED indicators when the relay was lastpowered, and therefore these indicators may also be on.

If either the alarm or trip, or both LEDs are on then these should be reset beforeproceeding with further testing. If the LEDs successfully reset (the LED goes out),there is no testing required for that LED because it is known to be operational.

Testing the alarm LED

The alarm LED can simply be tested by entering the password in the[0002 Password] cell as this will cause it to flash.


Testing the trip LED

The trip LED can be tested by initiating a manual circuit breaker trip from the relay.However, if the customer settings do not allocate output relays 3 or 7 in the relaymasks for circuit breaker tripping from the phase fault protection function(KCEG 142/152/242, KCGG 122/142 and KCEU 142, 242 relays) or earthfault protection function (KCEG 112 relay), the trip LED will operate during thesetting checks performed later. Otherwise the trip LED will need testing.

If testing the LED is necessary but neither output relay 3 or 7 has been assigned formanual circuit breaker tripping, with the password entered (use the [0002Password] cell if not already in this mode), set relay mask [0B0D CB Trip] bit 7to‘1’.

Set the [0010 CB Control] to ‘Trip’ and confirm the operation by pressing [F] then[+]. Check the trip LED to ensure it comes on.

Restoring password protection

To restore password protection (stopping changes to password-protected cells),press and hold the [F] key for over 1 second then press and hold the [0] key forover 1 second. Password protection will also be restored automatically 15 minutesafter the last key press. The alarm LED stops flashing to indicate that passwordprotection has been restored.

4.2.3 Liquid crystal display (LCD)

There are no in-built self test routines for the LCD. The display itself can be checkedby moving around the relay menu looking for pixels (the dots on the display usedto form the text) that are not working.

There is an integral backlight in the display that allows settings to be read in allconditions of ambient lighting. It is switched on when any key on the frontplate ismomentarily pressed and is designed to switch off 10 minutes after the last keypress. Check that the backlight does switch off as it will impose an unnecessaryburden on the station battery if it stays on.

4.2.4 Field voltage supply

The relay generates a field voltage of nominally 48V that should be used toenergise the opto-isolated inputs. Measure the field voltage across terminals 7and 8. Terminal 7 should be positive with respect to terminal 8 and the voltageshould be within the range 45V to 60V when no load is connected.

4.2.5 Capacitor trip voltage (KCEG 242 and KCEU 242 relays only)

The relay generates a capacitor trip voltage of nominally 50V. Measure the fieldvoltage across terminals 9 and 10. Terminal 9 should be positive with respect toterminal 10 and the voltage should be within the range 45V to 55V when no loadis connected.

4.2.6 Input opto-isolators

This test is to check that all the opto-isolated inputs are functioning correctly.The KCEG 112, KCGG 122 and KCGG 142 02 have only 3 inputs (L0, L1 andL2) while the remaining KCEG 142/152/242, KCGG 142 01 and KCEU 142/242 have the full 8 opto-isolated inputs (L0, L1, L2, L3, L4, L5, L6 and L7).

To allow the opto-isolated inputs to work, terminal 8 (field voltage supply negative)should be linked to terminal 52 for all models and additionally to 55 where therelay has 8 opto-isolated inputs.


The opto-inputs can then be individually energised by connecting terminal 7 (fieldvoltage supply positive) to the appropriate opto-isolated input listed in Table 4.

Note: The opto-isolated inputs may be energised from an external 50V battery insome installations. Check that this is not the case before connecting the fieldvoltage otherwise damage to the relay may result.

Opto-isolator L0 L1 L2 L3 L4 L5 L6 L7

Terminal number 46 48 50 45 47 49 51 53

Table 4: Opto-isolator connections

The status of each opto-isolated input can be viewed using cell [0020 Log Status].When each opto-isolated input is energised one of the characters on the bottomline of the display will change to indicate the new state of the inputs. The numberprinted on the frontplate under the display will identify which opto-isolated inputeach character represents. A ‘1’ indicates an energised state and a ‘0’ indicates ade-energised state..

4.2.7 Output relays

This test is to check that all the output relays are functioning correctly.

With the password entered (use the [0002 Password]), set relay mask [0B0D CBTrip] bit 0 to ‘1’ and the rest (bits 1 to 7) to ‘0’.

Connect an audible continuity tester across the terminals corresponding to outputrelay 0 given in Table 5. Select the [0010 CB Control] cell and press the [+] keyuntil ‘Trip CB’ is displayed. Press the [F] once followed by the [+] key to confirmthe change.

Operation of output relay 0 will be confirmed by the continuity tester sounding forthe duration of the trip pulse time in the [0906 tTRIP] cell.

Repeat the test for output relays 1 to 3 inclusive for a KCEG 112, KCGG 142 02or KCGG 122 relay and relays 1 to 7 inclusive for the remaining KCEG 142/152/242, KCGG 142 or KCEU 142/242 relays.

Output relay [CB Trip] Mask setting Terminal numbers0 0 0 0 0 0 0 0 1 30 and 32

1 0 0 0 0 0 0 1 0 34 and 36

2 0 0 0 0 0 1 0 0 38 and 40

3 0 0 0 0 1 0 0 0 42 and 44

4 0 0 0 1 0 0 0 0 29 and 31

5 0 0 1 0 0 0 0 0 33 and 35

6 0 1 0 0 0 0 0 0 37 and 39

7 1 0 0 0 0 0 0 0 41 and 43

Table 5: Settings for output tests

If an output relay is found to have failed, an alternative relay can be temporarilyre-allocated until such time as the relay module can be repaired or a replacementcan be installed.


To restore password protection (stopping changes to password-protected cells),press and hold the [F] key for over 1 second then press and hold the [0] key forover 1 second. Password protection will also be restored automatically 15 minutesafter the last key press. The alarm LED stops flashing to indicate that passwordprotection has been restored.

4.2.8 Communications ports

This test should only be performed where the relay is to be accessed from a remotelocation and a portable PC has not been used to read and change settings duringcommissioning.

It is not the intention of the test to verify the operation of the complete system fromthe relay to the remote location, just the relays K-bus circuitry and the protocolconverter.

Connect a portable PC running the appropriate software to the incoming (remotefrom relay) side of the protocol converter and ensure that the communicationssettings in the application software are set the same as those on the protocolconverter.

Check that communications with the relay can be established.

4.2.9 Current inputs

This test verifies the accuracy of current measurement is within the acceptabletolerances.

All relays will leave the factory set for operation at a system frequency of 50Hz.If operation at 60Hz is required then this must be set in cell [0009 Freq]. Press the[+] key until the frequency is 60Hz, then press the [F] key once followed by the [+]key to confirm the change.

Apply rated current to each current transformer input in turn, checking itsmagnitude using a multimeter. Refer to Table 6 for the corresponding reading inthe relays MEASURE 1 column and record the value displayed. All measuredcurrent values on the relay should equal the applied current multiplied by thecurrent transformer ratio set in the [0502 CT Ratio] cell for earth fault currenttransformer inputs or [0602 CT Ratio] cell for phase current transformer inputs, asapplicable. The acceptable tolerance is ±5%.

Current applied to Menu cell

Terminals 21 and 22 [0201 Ia] (KCEG 142/152/242, KCGG 122/142)and KCEU 142/242

Terminals 23 and 24 [0202 Ib] (KCEG 142/152/242, KCGG 122/142)and KCEU 142/242

Terminals 25 and 26 [0203 Ic] (KCEG 142/152/242, KCGG 122/142)and KCEU 142/242

Terminals 27 and 28 [0204 Io] KCEG 112/142/152/242,(KCGG 122/142 and KCEU 142/242)Table 6: Current inputs and corresponding displayed values


4.2.10 Voltage inputs (KCEG and KCEU relays only)

This test verifies the accuracy of voltage measurement is within the acceptabletolerances for relays with directional protection functions.

Apply rated voltage to each voltage transformer input in turn, checking itsmagnitude using a multimeter. Refer to Table 7 for the corresponding reading inthe relays MEASURE 1 column and record the value displayed. All measuredvoltage values on the relay should equal the applied voltage multiplied by thevoltage transformer ratio set in the [0503 VT Ratio] cell for earth fault voltagetransformer inputs or [0603 VT Ratio] cell for phase voltage transformer inputs, asapplicable. The acceptable tolerance is ±5%.

Voltage applied to Menu cell

Terminals 17 and 20 [0208 Va] (KCEG 142/242 and KCEU 142/242)

Terminals 18 and 20 [0209 Vb] (KCEG 142/242 and KCEU 142/242)

Terminals 19 and 20 [020A Vb] (KCEG 142/242 and KCEU 142/242)[020B Vo] (KCEG 112/152)

Table 7: Voltage inputs and corresponding displayed values

4.2.11 Energisation from line current transformers (KCEG 242 and KCEU 242 only)

This test ensures that the KCEG 242 or KCEU 242 relays will operate from the linecurrent transformers should the auxiliary voltage be unavailable or has failed. Thecurrents used in the tests are the minimum values for which the relay shouldoperate, regardless of setting.

Remove the auxiliary supply from the relay. Inject the current stated in Table 8 tothe relay terminals specified.

In each case the relay should power up correctly with the LCD showing the defaultdisplay and the green healthy LED illuminated.

Repeat the field supply and capacitor trip voltage tests (4.2.4 and 4.2.5respectively) with the relay powered from the injected current.

Injected current TerminalsInject into Link together

0.4 x In 21 and 23 22 and 2425 and 21 26 and 2223 and 25 24 and 26

0.2 x In 23 and 28 24 and 27

Table 8: Injected currents for line current transformer energisation tests

Note: For 0.2 x In, the relay may chatter due to the loading effect of theenergised output relays. This is unlikely to occur when the relay is inservice because it will not be powered from the earth fault current only.


Section 5. SETTING TESTS

The setting checks ensure that all the predetermined settings for the particularinstallation (customer’s settings) have been correctly applied to the relay and thatthe relay is operating correctly at those settings. If the customer settings are notavailable, ignore sections 5.1 and 5.2 and perform the tests in section 5.3 at thefactory default settings.

5.1 Apply customer settings

There are two methods of applying the settings:

• Downloading them to the relay using a portable PC running the appropriatesoftware via a KITZ protocol converter. If a KITZ is not installed as part of thecustomer’s scheme, one will have to be temporarily connected to the K-Busterminals of the relay. This method is preferred as it is much faster and there isless margin for error.

If a setting file has been created by the customer and provided on a diskette,this will further reduce the commissioning time.

• Enter them manually via the relays operator interface.

5.2 Check settings

The settings applied should be carefully checked against the customer’s desiredsettings to ensure they have been entered correctly. However, this is not consideredessential if a customer-prepared setting file has been downloaded to the relayusing a portable PC.

There are two methods of checking the settings:

• Extract the settings from the relay using a portable PC running the appropriatesoftware via a KITZ protocol converter and compare with the customer’s originalsetting record. (For cases where the customer has only provided a printed copyof the required settings but a portable PC is available).

• Step through the settings using the relays operator interface and compare themwith the customer’s original setting record.

5.3 Demonstrate correct relay operation

This test, performed on a single element, demonstrates that the relay is functioningcorrectly at the customers chosen settings.The test performed will depend on theprotection functions provided by the relay under test. The test is usually on stage 1of the phase fault function, except KCEG 112 and KCEG 152 where stage 1 ofthe directional earth fault function is tested.

5.3.1 Non-directional phase fault test (KCGG 122/142 relays)

This test demonstrates that stage 1 of the KCGG phase fault function [t>] operateswithin the stated tolerance at the customer settings.

5.3.1.1 Connect the test circuit

Determine which output relay has been selected to operate when a t> trip occurs.If the trip outputs are phase-segregated (ie. a different output relay allocated foreach phase), the relay assigned in cell [0B08 tA>] should be used. The associatedterminal numbers can be found either from the external connection diagram(Appendix 3) or Table 5 above.

Connect the output relay so that its operation will trip the test set and stop the timer.


Connect the current output of the test set to terminals 21 and 22 (‘A’ phase currenttransformer input) of the relay and ensure that the timer will start when the currentis applied to the relay.

5.3.1.2 Perform the test

Ensure that the timer is reset.

Apply a current of twice the setting in cell [0605 I>] to the KCGG and note thetime displayed when the timer stops.

5.3.1.3 Check the operating time

Check that the operating time recorded by the timer is within the range shown inTable 9.

Curve Operating time at 2Is and TMS=1Nominal Range

DT [t>/DT] setting naSI30xDT 10.03 9.53 – 10.53VI30xDT 13.50 12.83 – 14.18EI10xDT 26.67 25.33 – 28.00LTI30xDT 120.0 114.00 – 126.00MI 7.61 7.23 – 7.99VI 14.06 13.35 – 14.76EI 19.04 18.09 – 20.00STI30xDT 1.78 1.69 – 1.87RECT 966 917 – 1014

Table 9: Characteristic operating times for I>

Note: The operating given in Table 9 are for a TMS of 1. Therefore, to obtain theoperating time for other TMS settings, the time given in Table 9 must bemultiplied by the relays actual TMS setting. This setting can be found incell [0606 t>/TMS]). In addition, there is an additional tolerance of up to0.04 second that should be taken into account.

5.3.2 Directional phase fault test (KCEG 142/242 and KCEU 142/242 relays)

This test demonstrates that stage 1of the KCEG or KCEU phase fault function [t>]operates within the stated tolerance at the customer settings. If cell [0601 PF Links]has been set to ‘0’, stage 1 [t>] function has been set for non-directional operationand hence should be tested as per a KCGG 142 (ie. use test 5.3.1).

If a KCEG 242 or KCEU 242 relay is being tested, it is recommended that therelay is energised from an auxiliary voltage supply as this will reduce the burdenimposed by the relay on the current injection test set.


Determine which output relay has been selected to operate when a t> trip occurs.If the trip outputs are phase-segregated (ie. a different output relay allocated foreach phase), the relay assigned in cell [0B08 tA>] should be used. The associatedterminal numbers can be found either from the external connection diagram(Appendix 3) or Table 5 above.



Connect the test equipment as shown in Figure 1. Care should be taken to ensurethat the correct polarities are connected to the phase angle meter. Adjust the phaseshifter so that the phase angle meter reads 0°.

Figure 1: Connections for directional phase fault tests

5.3.2.2 Perform boundary of operation test

Determine the relay characteristic angle (RCA) setting that has been applied to therelay by referring to cell [060D Char Angle].

Apply rated volts and a current above the [060D I>] setting to the relay.

Monitor the forward start output contact, assigned in the relay mask[0B06 I> Fwd], and the reverse start contact, assigned in the relay mask[0B07 I> Rev], to indicate when the relay is in the operate region. The contactstatus can be determined either by physically monitoring the output relay contactsthemselves using a continuity tester or observing cell [0021 Rly Status].

Note: If the customer settings have no output relays assigned in relay masks[0B06 I> Fwd] or [0B07 I> Rev] then an output relay should temporarilybe assigned in relay mask [0B06 I> Fwd]. This will allow the boundarytest to be performed.

Taking positive phase angles as the current leading the voltage and negativephase angles as the current lagging the voltage, adjust the phase shiftingtransformer so the phase angle meter reads 180°+RCA. Check that the reversestart contacts have closed and the forward start contacts are open.

Rotate the phase shifting transformer so the phase lag is decreasing or the phaselead is increasing on the phase angle meter and continue until the forward startcontacts close and the reverse contacts open. Note the angle on the phase anglemeter and check it is within the 5% of either RCA–90° or RCA+90°. Rotate thephase shifting transformer in the opposite direction to check the other operatingboundary.

If an output relay has been temporarily assigned in the relay mask [0B06 I> Fwd]to allow the boundary test to be performed, return the mask to the customer’ssetting.

ABCN

Phaseanglemeter

A

BC

N

18

19

21

22

R

VBC

IA

Relay


5.3.2.3 Perform the timing test


Apply a current of twice the setting in cell [0605 I>] to the relay and note the timedisplayed when the timer stops.


5.3.3 Directional earth fault function test (KCEG 112/152 relays)

This test demonstrates that stage 1 of the KCEG earth fault function (to>) operateswithin the stated tolerance at the customer settings.


Determine which output relay has been selected to operate when a to> trip occurs.The associated terminal numbers can be found either from the external connectiondiagram (Appendix 3) or Table 5 above.


Connect the test equipment as shown in Figure 2. Care should be taken to ensurethat the correct polarities are connected to the phase angle meter. Adjust the phaseshifter so that the phase angle meter reads 0°.

Figure 2: Connections for directional earth fault tests

5.3.3.2 Perform boundary of operation test

Determine the relay characteristic angle (RCA) setting that has been applied to therelay by referring to cell [050D Char Angle].

Apply a current above the [0505 Io>] setting and a polarising voltage above thethreshold voltage [050F Vop>] setting to the relay.

Monitor the forward start output contact, assigned in the [0B01 Io> Fwd] relaymask, and the reverse start contact, assigned in the [0B02 Io> Rev] relay mask, toindicate when the relay is in the operate region. The contact status can bedetermined either by physically monitoring the output relay contacts themselvesusing a continuity tester or observing cell [0021 Rly Status].

ABCN

A

N

V

Phaseanglemeter

ACurrentinjectiontest set

19

20

Vo

27

Io

28

Relay

BC


Note: If the customer settings have no output relays assigned in relay masks[0B01 Io> Fwd] or [0B02 Io> Rev] then an output relay shouldtemporarily be assigned in relay mask [0B01 Io> Fwd]. This will allow theboundary test to be performed.

Taking positive phase angles as the current leading the voltage and negativephase angles as the current lagging the voltage, adjust the phase shiftingtransformer so the phase angle meter reads 180°+RCA. Check that the reversestart contacts have closed and the forward start contacts are open.

The correct polarity of connection for operation with forward current flow is currentflowing in through terminal 27 and out of terminal 28.

Rotate the phase shifting transformer so the phase lag is decreasing or the phaselead is increasing on the phase angle meter and continue until the forward startcontacts close and the reverse contacts open. Note the angle on the phase anglemeter and check it is within the 5% of either RCA–90° or RCA+90°. Rotate thephase shifting transformer in the opposite direction to check the other operatingboundary.

If an output relay has been temporarily assigned in the relay mask [0B01 Io> Fwd]to allow the boundary test to be performed, return the mask to the customer’ssetting.

5.3.3.3 Perform the timing test


Depending on the rating of the phase meter being used, it may be necessary toshort-circuit it with a wire link or remove it entirely to prevent thermal damage dueto the currents used for the timing test.

Apply a current of twice the setting in cell [0505 Io>] to the KCEG and note thetime displayed when the timer stops.


Section 6. ON-LOAD CHECKS

Remove all test leads, temporary shorting leads, etc. and replace any externalwiring that has been removed to allow testing.

If it has been necessary to disconnect any of the external wiring from the relay inorder to perform any of the above tests, it should be ensured that all connectionsare replaced in accordance with the relevant external connection or schemediagram.

The following on-load measuring checks ensure that the external (customer) wiringto the current and voltage inputs is correct but can only be carried out if there areno restrictions preventing the energisation of the plant being protected.

6.1 Check current and voltage transformer connections(KCEG and KCEU relays)

These tests alone are not conclusive that the phase connections to the relay arecorrect. A phase angle measurement is required for conclusive testing.


6.1.1 Voltage connections

Measure the voltage transformer secondary voltages to ensure they are correctlyrated and check that the system phase rotation is correct using a phase rotationmeter.

If a KCEG 112 or KCEG 152 is being tested, it will not be possible to check thephase rotation as the directional earth fault protection functions are polarised froman open-delta voltage transformer winding.

Compare the values of the secondary phase voltages with the relays measuredvalues, which can be found in the MEASURE 1 menu column.

If the voltage transformer ratios (cells [0503 VT Ratio] and [0603 VT Ratio] forresidual and phase voltages respectively) are set to 1:1, the displayed values arein secondary volts. The relay values should be within 5% of the applied secondaryvoltages.

Otherwise, if the voltage transformer ratios (cells [0503 VT Ratio] and [0603 VTRatio] for residual and phase voltages respectively) are set greater than 1:1, thedisplayed values are in primary volts. In this case the relay values will be equal tothe applied secondary voltages multiplied by the appropriate voltage transformerratio setting. Again the relay values should be within 5%.

It should be noted that directional earth fault relays are not energised under normalload conditions and it is therefore necessary to simulate a phase to neutral fault tocheck the voltage transformer wiring.

6.1.2 Current connections

Measure the current transformer secondary values, and check that their polaritiesare correct by measuring the phase angle between the current and voltage.

Ensure the current flowing in the neutral circuit of the current transformers isnegligible.

Compare the values of the secondary phase currents with the relays measuredvalues, which can be found in the MEASURE 1 menu column.

If the current transformer ratios (cells [0502 CT Ratio] and [0602 CT Ratio] forearth and phase currents respectively) are set to 1:1, the displayed values are insecondary amperes. The relay values should be within 5% of the appliedsecondary currents.

Otherwise, if the current transformer ratios (cells [0502 CT Ratio] and [0602 CTRatio] for earth and phase currents respectively) are set greater than 1:1, thedisplayed values are in primary amperes. In this case the relay values will beequal to the applied secondary currents multiplied by the appropriate currenttransformer ratio setting. Again the relay values should be within 5%.

It should be noted that directional earth fault relays are not energised under normalload conditions and it is therefore necessary to simulate a phase to neutral fault.

6.2 Check current transformer connections (KCGG relays)

Measure the current transformer secondary values.

Ensure the current flowing in the neutral circuit of the current transformers isnegligible.

Compare the values of the secondary phase currents with the relays measuredvalues, which can be found in the MEASURE 1 menu column.


If the current transformer ratios (cells [0502 CT Ratio] and [0602 CT Ratio] forearth and phase currents respectively) are set to 1:1, the displayed values are insecondary amperes. The relay values should be within 5% of the appliedsecondary currents.

Otherwise, if the current transformer ratios (cells [0502 CT Ratio] and [0602 CTRatio] for earth and phase currents respectively) are set greater than 1:1, thedisplayed values are in primary amperes. In this case the relay values will beequal to the applied secondary currents multiplied by the appropriate currenttransformer ratio setting. Again the relay values should be within 5%.

It should be noted that earth fault relays are not energised under normal loadconditions and it is therefore necessary to simulate a phase to neutral fault. It istherefore necessary to temporarily disconnect one or two of the line currenttransformer connections to the relay and short the terminals of these currenttransformer secondary windings.

Section 7. FINAL CHECKS

The tests are now complete.

Remove all test or temporary shorting leads, etc. If it has been necessary todisconnect any of the external wiring from the relay in order to perform the wiringverification tests, it should be ensured that all connections are replaced inaccordance with the relevant external connection or scheme diagram.

If the circuit breaker operations counter should be zero, reset it using cell [0310Sum (ops)]. This will require the password to be entered in cell [0002 Password]beforehand.

However, if a replacement relay has been fitted, the circuit breaker maintenancecounter cell [0310 CB (ops)] and current squared counters (displayed in cells[0311 CBdutyA], [0312 CBdutyB] and [0313 CBdutyC]) may need to beincremented to the values on the old relay. The counter for the number of circuitbreaker can be incremented manually by operating the relay the required numberof times. In a similar way, the current squared counters can be incremented byapplying a number of secondary injection current pulses to the current inputs of therelay, but note that the counter will increment rapidly for large current values.

If a MMLG test block is installed, remove the MMLB01 test plug and replace theMMLG cover so that the protection is restored to service.

Ensure that all event records, fault records, disturbance records, alarms and LEDshave been reset before leaving the relay.

Replace the cover on the relay.


Section 8. PROBLEM SOLVING

Before carrying out any work on the equipment, the user should befamiliar with the ‘Safety Section’ and Chapter 2 ‘Handling andInstallation’, of this manual.

8.1 Password lost or not accepted

Relays are supplied with the password set to AAAA.

Only uppercase letters are accepted.

Password can be changed by the user, see Chapter 3, Section 3.

There is an additional unique recovery password associated with the relay whichcan be supplied by the factory, or service agent, if given details of its serialnumber.

The serial number will be found in cell [0008 Serial No.] and should correspond tothe number on the label at the top right hand corner of the frontplate of the relay.If they differ, quote the one in cell [0008 Serial No.].

8.2 Protection settings

8.2.1 Settings for high sets not displayed

For Group 1 settings:

Set cell [0601 PF Links] link 1 to ‘1’ to turn on I>> settings.

Set cell [0601 PF Links] link 2 to ‘1’ to turn on I>>> settings.

Set cell [0501 EF Links] link 1 to ‘1’ to turn on Io>> settings.

Set cell [0501 EF Links] link 2 to ‘1’ to turn on Io>>> settings.

For Group 2 settings:

Set cell [0801 PF Links] link 1 to ‘1’ to turn on I>> settings.

Set cell [0801 PF Links] link 2 to ‘1’ to turn on I>>> settings.

Set cell [0701 EF Links] link 1 to ‘1’ to turn on Io>> settings.

Set cell [0701 EF Links] link 2 to ‘1’ to turn on Io>>> settings.

8.2.2 Second setting group not displayed

Set cell [0003 SD Links] link 4 to ‘1’ to turn on the group 2 settings.

8.2.3 Function links can not be changed

Enter the password in cell [0002 Password] as these menu cells are protected.

Links are not selectable if associated text is not displayed.

8.2.4 Curve selection can not be changed

Enter the password in cell [0002 Password] as these menu cells are protected.

Curves may not have been selectable in the particular relay.


8.3 Alarms

If the watchdog relay operates, first check that the relay is energised from theauxiliary supply. If it is, then try to determine the cause of the problem byexamining the alarm flags in cell [0022 Alarms]. This will not be possible if thedisplay is not responding to key presses. Having attempted to determine the causeof the alarm it may be possible to return the relay to an operable state by resettingit. To do this, remove the auxiliary power supply from the relay for approximately10 seconds before re-establishing the supply. If the relay is powered from the CTcircuit as well, remove this source of supply also, possibly by withdrawing themodule from its case. The relay should return to an operating state.

Recheck the alarm status in cell [0022 Alarms] if the alarm LED is still indicating analarm state. The following notes will give further guidance:

8.3.1 Watchdog alarm

Auxiliary powered relays: the watchdog relay will pick up when the relay isoperational to indicate a healthy state, with its “normally open” contact closed.When an alarm condition that requires some action to be taken is detected, thewatchdog relay resets and its “normally closed” contact will close to give analarm.

Note: The green LED will usually follow the operation of the watchdog relay.

Dual powered relays: the watchdog relay operates in a slightly different way onthis version of the relay, because it does not initiate an alarm for loss of theauxiliary power supply. This is because the auxiliary power supply may be takenfrom an insecure source or the relay may be powered solely from the currentcircuit. Operation of the watchdog is therefore inverted so that it will pick-up for afailed condition, closing its “make” contact to give an alarm and in the normalcondition it will remain dropped-off with its “break” contact closed to indicate thatit is in a healthy state.

Note: The green LED will usually operate in the opposite way to the watchdogrelay (ie. the LED will be on when the watchdog relay is de-energised andvice versa).

There is no shorting contact across the case terminals connected to the “break”contact of the watchdog relay. Therefore, the indication for a failed/healthy relaywill be cancelled when the relay is removed from its case.

If the relay is still functioning, the actual problem causing the alarm can be foundfrom the alarm records in cell [0022 Alarms] (see Chapter 3, Section 7.1).

8.3.2 Cell [0022 Alarms] link 0 = ‘1’

For an ‘Uncfg’ configuration alarm, the protection is stopped and no longerperforming its intended function as there will be an error in the factoryconfiguration settings.

To return the relay to a servicable state, the initial factory configuration will have tobe reloaded and the relay re-calibrated. It is recommended that the work becarried out at the factory, or entrusted to an approved service centre.

8.3.3 Cell [0022 Alarms] link 1 = ‘1’

For an ‘Uncalib’ calibration alarm, the protection will still be operational but therewill be an error in its calibration that will require attention. It may be left runningprovided the error does not cause any problems with incorrect tripping.


To return the relay to a servicable state, the initial factory configuration will have tobe reloaded and the relay re-calibrated. It is recommended that the work becarried out at the factory, or entrusted to an approved service centre.

8.3.4 Cell [0022 Alarms] link 2 = ‘1’

A ‘Setting’ alarm indicates that the area of non-volatile memory where the selectedprotection settings are stored has been corrupted. The current settings should bechecked against those applied at the commissioning stage or any later changesthat have been made.

If a personal computer (PC) is used during commissioning then it is recommendedthat the final settings applied to the relay are copied to a floppy disk with the serialnumber of the relay used as the file name. The settings can then be readily loadedback into the relay if necessary, or to a replacement relay.

8.3.5 Cell [0022 Alarms] link 3 = ‘1’

The ‘No Service’ alarm flag can only be observed when the relay is in thecalibration or configuration mode when the protection programme will be stopped.

8.3.6 Cell [0022 Alarms] link 4 = ‘1’

The ‘No Samples’ alarm flag indicates that there is no output from the analogue todigital converter, although the relay will remain in service. If this flag should be setto ‘1’, please contact the factory or an approved service centre for advice.

8.3.7 Cell [0022 Alarms] link 5 = ‘1’

The ‘No Fourier’ alarm flag indicates that the Fourier analysis algorithm is nolonger running. If this flag should be set to ‘1’, please contact the factory or anapproved service centre for advice.

8.3.8 Cell [0022 Alarms] link 7 = ‘1’

The ‘CB ops’ alarm flag indicates that, since the operations counter was last reset,the circuit breaker has operated the number of times that has been set in cell[0C07 CB Ops>].

The circuit breaker operations counter can be viewed and reset using cell[0310 Sum (ops)].

8.3.9 Fault flags will not reset

These flags can only be reset when the flags Fn are being displayed or by resettingthe fault records (cell [0110 Clear=0]). For more details refer to Chapter 3,Section 4.15.

8.4 Records

8.4.1 Problems with event records

Fault records will only be generated if RLY3 is operated as this relay is the triggerto store the records.

Fault records can be generated in response to another protection operating if oneof its trip contacts is used to operate RLY3 via an opto-isolated input on the K relay.This will result in the fault values, as measured by the K relay, being stored at theinstant RLY3 resets. The flag display (cell [0102 Fn G1]) will include a flag toidentify the auxiliary input that initiated the record.

Fault currents recorded are lower than actual values, as the fault is interruptedbefore measurement is completed.


Few fault records can be stored when changes in the state of logic inputs and relayoutputs are stored in the event records. These inputs and outputs can generatemany events for each fault occurrence and limit the total number of faults that canbe stored. Setting cell [0003 SD Links] Link 7 to ‘0’ will turn off this feature andallow the maximum number of fault records to be stored.

The event records are erased if the auxiliary supply to the relay is lost for a periodexceeding the hold-up time of the internal power supply.

Events can only be read via the serial communication port and not on the LCD.

Any spare opto-isolated inputs may be used to log changes of state of externalcontacts in the event record buffer of the K relay. The opto-isolated input does nothave to be assigned to a particular function in order to achieve this (ie. it does nothave to be assigned in any of the input masks).

The oldest event is overwritten by the next event to be stored when the bufferbecomes full.

When a master station has successfully read a record, it usually clears itautomatically. When all records have been read, the event bit in the status bytewithin the master station programme is set to ‘0’ to indicate that there are nolonger any records to be retrieved.

8.4.2 Problems with disturbance records

Only one record can be held in the buffer and the recorder must be reset beforeanother record can be stored. Automatic reset can be achieved by setting functionlink [0003 SD Links] link 6 to ‘1’. It will then reset the disturbance recorder 3seconds after a current, greater than the undercurrent setting, has been restored tothe protected circuit.

The disturbance records are erased if the auxiliary supply to the relay is lost for aperiod exceeding the hold-up time of the internal power supply.

Disturbance records can only be read via the serial communication port. It is notpossible to display them on the LCD.

No trigger has been selected in cells [0C04 Logic Trig] or [0F05 Relay Trig] toinitiate the storing of a disturbance record.

The disturbance recorder is automatically reset on restoration of current above theundercurrent setting for greater than 3 seconds. Change function link [0003 SDLinks] link 6 to ‘0’ to select manual reset.

Post trigger (cell [0C03 Post Trigger]) is set to maximum value. Thus the relay ismissing the fault.

When a master station has successfully read a record, it will clear the recordautomatically and the disturbance record bit in the status byte within the masterstation programme will then be set to ‘0’ to indicate that there is no longer arecord to be retrieved.


8.5 Circuit breaker maintenance records

When a replacement relay is fitted, it may be desirable to increment the circuitbreaker maintenance counter (cell [0310 CB (ops)]) to the values of that on the oldrelay. The current squared counters (displayed in cells [0311 CBdutyA], [0312CBdutyB] and [0313 CBdutyC], can be incremented by applying a number ofsecondary injection current pulses to the current inputs of the relay, but note thatthe counter will increment rapidly for large current values. The counter for thenumber of circuit breaker operations (displayed in cell [0310 Sum (ops)]) can beincremented manually by operating the relay the required number of times.

The circuit breaker trip time for the last fault (cell [010B CB Trip Time]) cannot becleared to zero. This is to enable the master station to interrogate the relay for thisvalue as a supervisory function.

The circuit breaker maintenance counters are not incremented when anotherprotection trips the circuit breaker. Add a trip input from the protection to anauxiliary input of the K relay and arrange for relay RLY3 or RLY7 to operateinstantaneously in response to the input.

8.6 Communications

An address (cell [000B Rly Address]) cannot be automatically allocated if theremote change of setting has been inhibited by cell [0003 SD Links] link 0 beingset to‘0’. This must be first set to ‘1’. Alternatively, the address must be enteredmanually via the user interface on the relay.

An address (cell [000B Rly Address]) cannot be allocated automatically unless theaddress is first manually set to ‘0’. This can also be achieved by a globalcommand including the serial number of the relay.

Relay address set to 255, the global address for which no replies are permitted.

8.6.1 Measured values do not change

Values in the MEASUREMENTS (1) and MEASUREMENTS (2) columns are snap-shots of the values at the time they were requested. To obtain a value that varieswith the measured quantity it should be added to the poll list as described in theuser manual for the access software being used.

8.6.2 Relay no longer responding

Check if other relays that are further along the bus are responding. If this is thecase, the relays communication processor should be reset by removing theauxiliary supply from the relay for at least 10 seconds before re-energising it.This should not be necessary as the reset operation occurs automatically when therelay detects a loss of communication.

If relays further along the bus are not communicating, check to find out which areresponding to the master station. If some are responding, the position of the breakin the bus can be determined by deduction. If none is responding then check fordata on the bus or reset the communication port driving the bus with requests.

Check there are not two relays with the same address (cell [000B Rly Address]) onthe bus.

8.6.3 No response to remote control commands

Check that cell [0003 SD Links] link 0 is not set to ‘0’ as this will inhibit the relayfrom responding to remote commands. If this is the case set cell [0003 SD Links]link 0 to‘1’; a password will be required.


System data function links settings can not be performed over the communicationlink if the remote change of settings has been inhibited by setting cell[0003 SD Links] link 0 to ‘0’. Change [0003 SD Links] link 0 to ‘1’ manually viathe user interface on the relay first.

Relay is not identified in the Circuit Breaker Control Menu of the Protection AccessSoftware and Toolkit if two auxiliary circuit breaker contacts have not beenconnected to the opto-isolated inputs of the relay, to indicate its position via theplant status word (cell [000C Plnt Status]). Check input masks [0A0E CB Closed]and [0A0F CB Open] for correct opto-isolator allocations, and the connections tothe auxiliary contacts of the circuit breaker.

8.7 Output relays remain picked up

Relays remain picked-up when de-selected by link or mask.

If an output relay is operated at the time it is de-selected, either due to a softwarelink change or by de-selecting it in an output mask, it may remain operated untilthe K relay is powered down and up again. After such changes, it is advisable toremove the auxiliary supply from the relay for at least 10 seconds before re-energising it.

8.8 Thermal state

8.8.1 Thermal state reset to zero

If the thermal ammeters (displayed in cells [0404 IthA], [0405 IthB] and[0406 IthC] are reset using an opto-isolated input allocated in cell[0A11 Reset Ith], this will also reset the thermal state of the thermal protection.

8.8.2 Thermal ammeter time constants

The setting for the time constant (cell [0814 TC]) is shared between the thermalammeter and the thermal protection. Priority would normally be given to thethermal protection.

8.9 Erratic operation at directional characteristic boundaries

If commissioning testing is carried out using a digital secondary injection test set,there may be an apparent erratic operation at the boundaries of the directionalcharacteristic. This will be particularly noticeable when observing the operation ofthe start relay contacts, which is the method described in the commissioninginstructions in Section 5.3. This is caused by the transitional errors when changingdirection or applying signals instantaneously due to the output quantities changingin steps rather than linearly. This does not happen with all designs of digitalsecondary injection test set.

The problem is easily overcome by using the t>, t>>, t>>>, to>, to>> or to>>>outputs for indication of relay operation instead of I>. or Io>. These time delaysshould then be set to a minimum of 20ms. See also the notes in Chapter 4, Section6.10 of this manual.

The slight directional indecision of the start relays should not cause any problem asit will be covered by the short time delays that are applied in the blockingschemes.


Section 9. MAINTENANCE

9.1 Maintenance period

It is recommended that products supplied by ALSTOM T&D Protection & ControlLimited receive regular monitoring after installation. As with all products somedeterioration with time is inevitable. In view of the critical nature of many of theseproducts and in the case of protective relays, their infrequent operation, it isdesirable to confirm that they are operating properly at regular intervals.

The typical life of these products is about 20 years, although many are insatisfactory service considerably longer than this.

Maintenance periods will depend on many factors, such as:

• the operating environment

• the accessibility of the site

• the amount of available manpower

• the importance of the installation in the power system

• the consequences of failure

If a preventative maintenance policy exists within the customer’s organisation thenthe recommended product checks should be included in the regular programme.

It should be noted that K Range Midos relays are self-supervising and so requireless maintenance than earlier designs of relay. Most problems will result in analarm so that remedial action can be taken. However, some periodic tests could bedone to ensure that the relay is functioning correctly.

The following sections suggest checks that can be performed either remotely overthe communications link using a PC running appropriate software or at site.

9.2 Maintenance checks

Before carrying out any work on the equipment, the user should befamiliar with the ‘Safety Section’ and Chapter 2 ‘Handling andInstallation’, of this manual.

9.2.1 Remote testing

If the relay can be communicated with from a remote point via its serial port, thensome checks can be carried out without actually visiting the site.

9.2.1.1 Alarms

The alarm status should first be checked to identify if any alarm conditions exist.The alarm records (cell [0022 Alarms]) can then be read to identify the nature ofany alarm that may exist

9.2.1.2 Measurement accuracy

The values measured by the relay can be compared with known system values tocheck that they are in the approximate range that is expected. If they are, then theanalogue/digital conversion and calculations are being performed correctly.

9.2.1.3 Trip test

If the relay is configured to provide remote control of the circuit breaker then a triptest can be performed remotely in several ways:


1. If the relay provides phase overcurrent protection, read the load current on eachphase in the MEASURE 1 column. Reduce the stage 1 phase fault setting (cell[0605 I>]) to a known value that is less than the load current. The relay shouldtrip in the appropriate time for the given multiple of setting current and timemultiplier setting (cell [0606 t>/TMS]).

The settings can then be returned to their usual value and the circuit breaker re-closed.

Note: If setting group 2 is not being used for any other purpose, it could be usedfor this test by having a lower setting pre-selected and issuing a commandto change the setting group that is in use to initiate the tripping sequence.

2. If the relay is connected for remote control of the circuit breaker then a trip/close cycle can be performed. This method will not check as much of thefunctional circuit of the relay as the previous method but it will not need thesettings of the relay changed.

If a failure to trip occurs, view cell [0021 Rly Status] whilst the test is repeated.This will check that the output relay is being commanded to operate.

If the test trip is being performed using a trip/close cycle, the output relay assignedin cell [0B0D CB Trip] should operate and not the main trip relay used by theprotection functions.

If the assigned output relay is not responding then an output relay allocated to aless essential function may be re-allocated to the trip function to effect a temporaryrepair, but a visit to the site may be needed to effect a wiring change. See Chapter3, Section 4.14 for how to set output relay masks.

9.2.1.4 Circuit breaker maintenance

Maintenance records for the circuit breaker can be obtained at this time byreading cells [0310 Sum (ops)], [0311 CBdutyA], [0312 CBdutyB], and[0313 CBdutyC].

9.2.2 Local testing

When testing locally, similar checks to those for remote testing may be carried outto ensure the relay is functioning correctly.

9.2.2.1 Alarms

The alarm status LED should first be checked to identify if any alarm conditionsexist. The alarm records (cell [0022 Alarms]) can then be read to identify thenature of any alarm that may exist.

9.2.2.2 Measurement accuracy

The values measured by the relay can be checked against known values injectedinto the relay via the test block, if fitted, or injected directly into the relay terminals.Suitable test methods will be found in Section 4.2.9 and 4.2.10 of this chapterwhich deals with commissioning. These tests will prove the calibration accuracy isbeing maintained.

9.2.2.3 Trip test

If the relay is configured to provide a trip test via its user interface then this shouldbe performed to test the output trip relays. If the relay is configured for remotecontrol of the circuit breaker, the trip test will initiate the remote circuit breaker triprelay (assigned in cell [0B0D CB Trip]) and not the main trip relay used by the


protection functions. If the relay provides phase overcurrent protection, the maintrip relay should be tested by reducing the stage 1 phase fault setting (cell [0605I>]) to a known value that is less than the load current. The relay should trip in theappropriate time for the given multiple of setting current and time multiplier setting(cell [0606 t>/TMS]). The settings can then be returned to their usual value and thecircuit breaker re-closed.

Note: If setting group 2 is not being used for any other purpose, it could be usedfor this test by having a lower setting pre-selected and issuing a commandto change the setting group that is in use to initiate the tripping sequence.

If the assigned output relay is not responding then an output relay allocated to aless essential function may be re-allocated to the trip function to effect a temporaryrepair. See Chapter 3, Section 4.14 for details on how to set output relay masks.

9.2.2.4 Circuit breaker maintenance

Maintenance records for the circuit breaker can be obtained at this time byreading cells [0310 Sum (ops)], [0311 CBdutyA], [0312 CBdutyB] and [0313CBdutyC].

9.2.2.5 Additional tests

Additional tests can be selected from the Commissioning Instructions as required.

9.3 Method of repair

Before carrying out any work on the equipment, the user should befamiliar with the ‘Safety Section’ and Chapter 2 ‘Handling andInstallation’, of this manual. This should ensure that no damage iscaused by incorrect handling of the electronic components.

9.3.1 Replacing a PCB

Re-calibration is not usually required when a PCB is replaced unless it happens tobe one of the two boards that plugs directly on to the left hand terminal block asthese directly affect the calibration.

9.3.1.1 Replacement of user interface

Withdraw the module from its case.

Remove the four screws that are placed one at each corner of the front plate.

Remove the front plate.

Lever the top edge of the user interface board forwards to unclip it from itsmounting.

Pull the PCB upwards to unplug it from the connector at its lower edge.

Replace with a new interface board and re-assemble in the reverse order.

9.3.1.2 Replacement of main processor board

This is the PCB at the extreme left of the module, when viewed from the front.

To replace this board:

First remove the screws holding the side screen in place. There are two screwsthrough the top plate of the module and two more through the base plate.

Remove screen to expose the PCB.

Remove the two retaining screws, one at the top edge and the other directly belowit on the lower edge of the PCB.


Separate the PCB from the sockets at the front edge of the board. Note that theyare a tight fit and will require levering apart, taking care to ease the connectorsapart gradually so as not to crack the front PCB card. The connectors are designedfor ease of assembly in manufacture and not for continual disassembly of the unit.

Re-assemble in the reverse of the above sequence, making sure that the screenplate is replaced with all four screws securing it.

9.3.1.3 Replacement of auxiliary expansion board

This is the second board from the left hand side of the module.

Remove the processor board as described in 9.3.1.2 above.

Remove the two securing screws that hold the auxiliary expansion board in place.

Unplug the PCB from the front bus as described for the processor board andwithdraw.

Replace in reverse order of the above sequence, making sure that the screen plateis replaced with all four screws securing it.

9.3.2 Replacing output relays

The main processor and auxiliary expansion boards are removed and replaced asdescribed in Section 9.3.1.2 and 9.3.1.3 above respectively.

It should be noted when replacing output relays that the PCB’s have through platedholes. Care must therefore be taken not to damage these holes when a componentis removed, otherwise solder may flow through the hole to make a goodconnection to the tracks on the component side of the PCB.

9.3.3 Replacing the power supply board

Remove the two screws securing the right hand terminal block to the top plate ofthe module.

Remove the two screws securing the right hand terminal block to the bottom plateof the module.

Unplug the back plane from the power supply board.

Remove the securing screws at the top and bottom of the power supply board.

Withdraw the power supply board from the rear, unplugging it from the front bus.

Re-assemble in the reverse order of the above sequence.

9.3.4 Replacing the back plane (size 4 and 6 cases)

Remove the two screws securing the right hand terminal block to the top plate ofthe module.

Remove the two screws securing the right hand terminal block to the bottom plateof the module.

Unplug the back plane from the power supply board.

Twist outwards and around to the side of the module.

Replace the PCB and terminal block assembly.

Re-assemble in the reverse order of the above sequence.


9.4 Recalibration

Re-calibration is not usually required when a PCB is replaced unless it happens tobe one of the two boards that plugs directly on to the left hand terminal block asthis one directly affects the calibration.

Although it is possible to carry out recalibration on site, this requires test equipmentwith suitable accuracy and a special calibration programme to run on a PC. It istherefore recommended that the work is carried out at the factory, or entrusted toan approved service centre.

After calibration, the relay will need to have all the settings required for theapplication re-entered if a replacement board has been fitted. Therefore, it is usefulif a copy of the settings is available on a floppy disk. Although this is not essential,it can reduce the time taken to re-enter the settings and hence the time theprotection is out of service.



Relays

Service Manual

Appendix 1Relay Characteristic Curves

SERVICE MANUAL R8551CKCGG 122, 142 Appendix 1KCEG 112, 142, 152, 242 ContentsKCEU 142, 242

1. TIME/CURRENT CHARACTERISTICS 1Figure 1: Operating times KCGG I>>, I>>>, Io>> and Io>>> 1Figure 2: Operating times KCEG I>>, I>>>, Io>> and Io>>> 1

2. RELAY CHARACTERISTIC CURVES 2Figure 3: IDMT curves: IEC and special application curves 2Figure 4: IDMT curves: ANSI/IEEF curves 3

3. THERMAL TIME/CHARACTERISTIC WITH PREFAULT LOAD 4Figure 4: Thermal time/current characteristic with prefault load 4

SERVICE MANUAL R8551CKCGG 122, 142 Appendix 1KCEG 112, 142, 152, 242 Page 1 of 4KCEU 142, 242

Section 1. TIME/CURRENT CHARACTERISTICS

10010

Multiple of setting (xIs)

1

15

0

30

45

60

75

90

105

120

135

150

Ope

ratin

g tim

e (m

s)

Maximum

Minimum

10010

Multiple of setting (xIs)

1

15

0

30

45

60

75

90

105

120

135

150

Ope

ratin

g tim

e (m

s)

Maximum

Minimum

Figure 1: Operating times KCGG I>>, I>>>, Io>> and Io>>>

Figure 2: Operating times KCEG I>>, I>>>, Io>> and Io>>>


Section 2. RELAY CHARACTERISTIC CURVES

Figure 3: IDMT curves: IEC and special application curves

LTI 30xDT Long time inverse

SI 30xDT* Standard inverse

EI 10xDT* Extremely inverse

VI 30xDT* Very inverse

STI 30xDT Shot time inverse

*IEC standard characteristic All characteristics are definite time above 30x except extremely inverse.

STI 30xDT

VI 30xDT

EI 10xDT

SI 30xDT

LTI 30xDT

1 10 100

Multiples of setting

10000

1000

100

10

1

0.1

Ope

ratin

g tim

e (se

cond

s)

Rectifiercurve


Figure 4: IDMT curves: ANSI/IEEF curves

10000

1000

100

10

1

0.1

1 10 100

EI

VI

MI

Multiples of setting

Ope

ratin

g tim

e (se

cond

s)

MI Moderately inverse

VI Very inverse

EI Extremely inverse

All characteristics are definite time above 30x except extremely inverse.


Section 3. THERMAL TIME/CHARACTERISTIC WITH PREFAULTLOAD

Figure 5: Thermal time/current characteristic with prefault load

1

Current (xlth>)

0.001

No pre-fault load

Time

(x t)

Pre-fault load at50% thermal state

2 3 4 5 6

0.010

0.100

1.000

10.000





Relays

Service Manual

Appendix 2Logic Diagrams

SERVICE MANUAL R8551DKCGG 122, 142 Appendix 2KCEG 112, 142, 152, 242 ContentsKCEU 142, 242

CONTENTS

Figure 1a: Scheme logic diagram KCGG 122 1Figure 1b: Scheme logic diagram KCGG 122 2Figure 2a: Scheme logic diagram KCGG 142 3Figure 2b: Scheme logic diagram KCGG 142 4Figure 3a: Scheme logic diagram KCEG 112 5Figure 3b: Scheme logic diagram KCEG 112 6Figure 4a: Scheme logic diagram KCEG 142/242 7Figure 4b: Scheme logic diagram KCEG 142/242 8Figure 5a: Scheme logic diagram KCEG 152 9Figure 5b: Scheme logic diagram KCEG 152 10Figure 6a: Scheme logic diagram KCEU 142/242 11Figure 6b: Scheme logic diagram KCEU 142/242 12

SERVICE MANUAL R8551DKCGG 122, 142 Appendix 2KCEG 112, 142, 152, 242 Page 1 of 12KCEU 142, 242

Figure 1a: Scheme logic diagram KCGG 122 (continued in Figure 1b)

&

&0

1

&

&

&

&0

1

&0

1

&0

1

0

1

01

0

1

01


Latch flagsGenerate fault records &copy to event records

0

1

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 07 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 17 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0



0A01 BLK to >0B03 to>

Io>

Stage 1earth fault

Startearth fault

Stage 2earth fault

Stage 3earth fault

Stage 1overcurrent

Startovercurrent

Stage 2overcurrent

Broken conductorstage 3overcurrent

Circuit breakercontrol

Breaker failprotection

Fault recordand flag latchinitiation

0A02 BLK to>>EF1

EF2

PF1

PF2

SD2

LOGA

LOG7

0A03 BLK to>>>

0A04 BLK t>

0A05 BLK t>>

0A06 BLK t>>>

0A07 L Trip

0A08 L Close

0A09 Ext. Trip

0B01 Io> Start

0B04 to>>

0B05 to>>>

0B09 t>

0B06 I> Start

0B0B t>>

0B0C t>>>

0B0D CB Trip

0B0E CB Close

0B0F CB Fail

Io>>

Io>>>

I>

I>>

I>>>

RLY3

RLY7

I>Io>

LOG9

LOG2

to>

to>>

to>>>

t>

t>>

t>>>

tTrip

tCloseReset

tBFI<

Io<

07 6 5 4 3 2 1

1

1

1 1

1

11

1

Latch red trip LED1


Figure 1b: Scheme logic diagram KCGG 122

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0 7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

0

1

0

17 6 5 4 3 2 1 07 6 5 4 3 2 1 00

101

01

01

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

0

17 6 5 4 3 2 1 07 6 5 4 3 2 1 0

01

01

01

01

01

7 6 5 4 3 2 1 0

Remote set Grp2

Remote reset Grp1

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0 Load Shed Level 1

0

1

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0 Load Shed Level 2

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0 Load Shed Level 3

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

01 7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

tAux1

Disturbancerecorder reset

Auxiliarytimers

Loss of load/stage 4 EP

Cold loadstart

Settingcontrolgroup

Load sheddingplant status

Thermalphase element

Circuitbreakeralarms

SD8

LOG3

LOG4

SD3

PF0

LOG0

0A0A Aux1

0A0B Aux2

Recorderstopped

Recorderstopped

0A0C Aux3

0A0D Stg Grp 2

0A0E CB Closed Ind

0D0F CB Open Ind

0A10 CB Bus 2

I<

I<

Io<

0A11 Reset Ith

Alarm

TripThermalreset

Plantstatusword

SD5

SD6SD8

0B10 Aux1

0B11 Aux2

0B12 Aux3

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 00B14 Level 1

0B15 Level 2

0B16 Level 3

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 00B17 th Alarm

0B18 th Trip

0B19 CB Alarm

LOG6

LOGB

LOG5

SD4

Set 1Reset 0

Change tosetting group 2

Reset trip flags

Resetdisturbancerecorder

tAux1

3Sec

tAux2

tAux3

CB (ops) >

CB duty >

³1

³1

³1

³1

³1

SD

LOG

EF1

EF2

PF1PF2

F E D C B A 9 8 7 6 5 4 3 2 1 0 F E D C B A 9 8 7 6 5 4 3 2 1 0 F E D C B A 9 8 7 6 5 4 3 2 1 0

LOG8


Figure 2a: Scheme logic diagram KCGG 142 (continued in Figure 2b)

>=1

0B03 to> Stage 1earth fault

Startearth fault

Stage 2earth fault

Stage 3earth fault

Blk to>>0A02

Blk to>>>0A03

EF1

EF2

Blk t>0A04

01

0A01 Blk to>

&

to>>

to>&

to>>>

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

&

&

01

to>>0B04

0B05

7 6 5 4 3 2 1 0&

tB>0B09

tA>0B08

tC>0B0At>

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0Io> Start0B01

7 6 5 4 3 2 1 0

to>>>7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

Io>

Io>>

Io>>>

I>

& 7 6 5 4 3 2 1 0I> Start0B06

Stage 1overcurrent

Startovercurrent

Blk t>>0A057 6 5 4 3 2 1 0

& t>>

I>>

>= 1

>= 1PF1

01

7 6 5 4 3 2 1 0t>>0B0B Stage 2

overcurrent

Blk t>>>0A067 6 5 4 3 2 1 0

& t>>>

I>>>

PF201

7 6 5 4 3 2 1 0t>>>0B0C Broken conductor

Stage 3overcurrent

I<

PFC01

>= 1

&

7 6 5 4 3 2 1 0Trip circuit breaker


tTRIP

tCLOSEReset

0A07 L TRIP

7 6 5 4 3 2 1 00A08 L CLOSE

7 6 5 4 3 2 1 00B0D CB TRIP

7 6 5 4 3 2 1 00B0E CB CLOSE

Circuitbreakercontrol

SD201

>= 1

>= 1

7 6 5 4 3 2 1 00A09 EXT. TRIP

>=1>=1

7 6 5 4 3 2 1 00B0F CB FAILtBF

RLY3


>= 1

LOG901

LOG201

>=1

I<

Io<

RLY7

LOGA01


>=1Latch flags generate faultrecord and copy to eventrecords.

I>

Io>

>=1

LOG701

PF7

0

1

1

2/3

Latch red trip LEDFault recordand flag latchinitiation


Figure 2b: Scheme logic diagram KCGG 142

0B10 Aux1 Underfrequency

Loss of load/stage 4 EF

SD801

0A0A Aux1tAux1

tAux2

7 6 5 4 3 2 1 0

3sec

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

F<I<

Cold loadstart

Setting groupcontrol




PFD01

0B11 Aux2

0A0B Aux2 Disturbancerecorderreset

Auxiliarytimers7 6 5 4 3 2 1 0 >= 1

>= 1

LOG301

LOG401

Recorderstopped

&I<

Io<

tAux3

LOGB0

1>= 1

LOG8

01

0A0C Aux37 6 5 4 3 2 1 0

LOG6

0

1

>= 10A0D Stg Grp 27 6 5 4 3 2 1 0

7 6 5 4 3 2 1 00B12 Aux3

LOG501

Remote set Grp2

Remote set Grp1

Set 1Reset 0

SD301

SD401


7 6 5 4 3 2 1 0

Plantstatusword

7 6 5 4 3 2 1 00D0F CB Open Ind

7 6 5 4 3 2 1 00A10 CB Bus 2

0A0E CB Closed Ind7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 00B15 Level 2

7 6 5 4 3 2 1 00B16 Level 3

0B14 Level 1

7 6 5 4 3 2 1 00B17 th Alarm

7 6 5 4 3 2 1 00B18 th Trip

>= 1

>= 1

Alarm

TripThermal

reset

PF0

01

7 6 5 4 3 2 1 00A11 Reset Ith

>= 1CBduty>

LOG001

CB(ops)>

7 6 5 4 3 2 1 00B19 CB Alarm

SD501

SD801

SD601

Recorderstopped

Reset trip flags

Resetdisturbance

recorder

Load shed level 1

Load shed level 2

Load shed level 3

SD

LOGF E D C B A 9 8 7 6 5 4 3 2 1 0

EF1

EF2

PF1

PF2F E D C B A 9 8 7 6 5 4 3 2 1 0 F E D C B A 9 8 7 6 5 4 3 2 1 0


Figure 3a: Scheme logic diagram KCEG 112 (continued in Figure 3b)

>=1

>=1

0A01 Blk to>

Io>

FWD

EF3

Blk to>>

Io>>

&

FWD

EF40

REV

Io<

0

&

0 0EF4 EF5

0A02

EF11

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

Blk to>>>

Io>>>

FWD

EF50

1

0A03

EF21

to>>>7 6 5 4 3 2 1 0

&

to>>

to>

7 6 5 4 3 2 1 0SD2 TRIP CIRCUIT BREAKER

TRIP CIRCUIT BREAKER

Io>

Stage 1earth fault

to>>

Fwd Start

7 6 5 4 3 2 1 00B03 to>

& 7 6 5 4 3 2 1 00B01

& 7 6 5 4 3 2 1 0Io>Rev Start0B02

7 6 5 4 3 2 1 00B04

to>>>7 6 5 4 3 2 1 0

0B05

>=1

>=1

tTRIP

tCLOSEReset

0A07 L TRIP

7 6 5 4 3 2 1 00A08 L CLOSE

LOGA1

LOG91>=1

1

7 6 5 4 3 2 1 00A09 EXT. TRIP

>=1>=1

LOG21

7 6 5 4 3 2 1 00B0D CB TRIP

7 6 5 4 3 2 1 00B0E CB CLOSE

7 6 5 4 3 2 1 00B0E CB FAILtBF

RLY3

RLY7

LOG7

01

Io>

Startearth fault

Stage 2earth fault

Stage 3earth fault



0

0

111

1

0

0



Latch red trip LED

>=1



Figure 3b: Scheme logic diagram KCEG 112

Recorder stopped

1LOG8

Disturbancerecorderreset

7 6 5 4 3 2 1 00A0A AUX1

tAUX1 7 6 5 4 3 2 1 00B10 AUX1

7 6 5 4 3 2 1 00A0B AUX2

>=1

1

CB (0ps)>

SD8

LOG4

01

>=1

Io<

tAUX2 7 6 5 4 3 2 1 00B11 AUX2

1SD8

1SD6

Recorderstopped Reset

disturbancerecorder

LOG6

>=1 tAUX31

7 6 5 4 3 2 1 00B121 AUX3

7 6 5 4 3 2 1 00A0C AUX3

LOG51

>=17 6 5 4 3 2 1 0

0A0D STG GRP 2 SD41


Set 1Reset 0

Remote set Grp2

Remote reset Grp1

SD31

7 6 5 4 3 2 1 00A0E CB CLOSED IND

7 6 5 4 3 2 1 00A0F CB OPEN IND

7 6 5 4 3 2 1 00A10 CB BUS 2

Plantstatusword

7 6 5 4 3 2 1 00B14 LEVEL 1

7 6 5 4 3 2 1 00B15 LEVEL 2

7 6 5 4 3 2 1 00B16 LEVEL 3

LOAD SHED LEVEL 1

LOAD SHED LEVEL 2

LOAD SHED LEVEL 3

LOG01 >=1 7 6 5 4 3 2 1 0

0B19 CB ALARM

tAux1


Cold loadstart



Cicuit breakeralarms

SD

LOGF E D C B A 9 8 7 6 5 4 3 2 1 0

EF1

EF2F E D C B A 9 8 7 6 5 4 3 2 1 0

PF1

PF2F E D C B A 9 8 7 6 5 4 3 2 1 0

0

0

0

0

0 0

0

0

0

0

LOGB


Figure 4a: Scheme logic diagram KCEG 142/242 (continued in Figure 4b)

Stage 3earth fault

Stage 1overcurrent

Startovercurrent

Stage 2overcurrent

Broken conductorStage 3overcurrent

PF5

Fwd0

1

Stage 1earth fault

Startearth fault

Stage 2earth fault

& to>

Io>

& t>

EF301

EF401

EF501

0A01 Blk to>7 6 5 4 3 2 1 0 0B03 to>

7 6 5 4 3 2 1 0

&FWD

REV

&

0B01 Io> Fwd Start7 6 5 4 3 2 1 0

0A02 Blk to>>7 6 5 4 3 2 1 0

EF401

EF101

& to>>

0B02 Io> Rev Start7 6 5 4 3 2 1 0

0B04 to>>7 6 5 4 3 2 1 0

Io>> FWD

0A03 Blk to>>>7 6 5 4 3 2 1 0

EF50

1

EF201

& to>>>0B05 to>>>7 6 5 4 3 2 1 0

Io>>> FWD EFE0

1

0A04 Blk t>7 6 5 4 3 2 1 0

REV

0B09 tB>7 6 5 4 3 2 1 0

0B08 tA>7 6 5 4 3 2 1 0

0B0A tC>7 6 5 4 3 2 1 0

&

&

&PF30

1

REV

FWD

I> PF4

0

1

PF5

0

1

PFF01

2 1

&PFF01

2 1

0B06 I> Fwd Start7 6 5 4 3 2 1 0

PFF01

2 1

PFF01

2 1

&0B07 I> Rev Start7 6 5 4 3 2 1 0

0B0B t>>7 6 5 4 3 2 1 0& t>>

0A05 Blk t>>7 6 5 4 3 2 1 0

PF101

PF4

FwdI>>

PFC01 I<

0A06 Blk t>>>7 6 5 4 3 2 1 0

&1

PF70

2

11

0B0C t>>>& t>>> 7 6 5 4 3 2 1 0

PFF0

0

1

PFE

0

1Rev

PF201 I>>>

7 6 5 4 3 2 1 0TRIP CIRCUIT BREAKER

CLOSE CIRCUIT BREAKER

tTRIP

tCLOSEReset

0A07 L Trip

7 6 5 4 3 2 1 00A08 L Close

7 6 5 4 3 2 1 00B0D CB Trip

7 6 5 4 3 2 1 00B0E CB Close


SD201

>= 1

>= 1

7 6 5 4 3 2 1 00A09 Ext. Ttrip

>=1>=1

7 6 5 4 3 2 1 00B0F CB FailtBF

RLY3


>= 1

LOG901

LOG201

>=1

I<

Io<

RLY7

LOGA01

I>

Io>

>=1

LOG701

1

>=1

>=1



Latch red trip LED


Figure 4b: Scheme logic diagram KCEG 142/242



SD801

0A0A Aux1tAux1

tAux2

7 6 5 4 3 2 1 0

3sec

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

F<I<

Cold loadstart





PFD01

0B11 Aux2


Auxiliarytimers7 6 5 4 3 2 1 0 >= 1

>= 1

LOG301

LOG401

Recorderstopped

&I<

Io<

tAux3LOGB

01

>= 1

LOG801

0A0C Aux37 6 5 4 3 2 1 0

LOG6

01

>= 10A0D Stg Grp 27 6 5 4 3 2 1 0

7 6 5 4 3 2 1 00B12 Aux3

LOG501

Remote set Grp2

Remote set Grp1

Set 1Reset 0

SD301

SD401


7 6 5 4 3 2 1 0

Plantstatusword

7 6 5 4 3 2 1 00D0F CB Open Ind

7 6 5 4 3 2 1 00A10 CB Bus 2

0A0E CB Closed Ind7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 00B15 Level 2

7 6 5 4 3 2 1 00B16 Level 3

0B14 Level 1

7 6 5 4 3 2 1 00B17 th Alarm

7 6 5 4 3 2 1 00B18 th Trip

>= 1

>= 1

Alarm

TripThermal

reset

PF0

01

7 6 5 4 3 2 1 00A11 Reset Ith

>= 1CBduty>

LOG001

CB(ops)>

7 6 5 4 3 2 1 00B19 CB Alarm

SD501

SD801

SD601 Recorder

stopped

Reset trip flags

Resetdisturbance

recorder

Load shed level 1

Load shed level 2

Load shed level 3

SD

LOGF E D C B A 9 8 7 6 5 4 3 2 1 0

EF1EF2

PF1

PF2F E D C B A 9 8 7 6 5 4 3 2 1 0 F E D C B A 9 8 7 6 5 4 3 2 1 0

PF801

V< PF901

&

>= 1

tV< 7 6 5 4 3 2 1 00B13 tV<

Undervoltage


Figure 5a: Scheme logic diagram KCEG 152 (continued in Figure 5b)


>=1

RLY7

LOGA01

I>

Io>

>=1

LOG701

>=1

>=1



Latch red trip LED

Stage 1overcurrent

Startovercurrent

Stage 2overcurrent


Stage 1earth fault

Startearth fault

Stage 2earth fault

& to>

Io>

& t>

EF301

EF401

EF501

0A01 Blk to>7 6 5 4 3 2 1 0 0B03 to>

7 6 5 4 3 2 1 0

&FWD

REV

&

0B01 Io> Fwd Start7 6 5 4 3 2 1 0

0A02 Blk to>>7 6 5 4 3 2 1 0

EF401

EF101

& to>>

0B02 Io> Rev Start7 6 5 4 3 2 1 0

0B04 to>>7 6 5 4 3 2 1 0

Io>>FWD

0A04 Blk t>7 6 5 4 3 2 1 0 0B09 tB>

7 6 5 4 3 2 1 0

0B08 tA>7 6 5 4 3 2 1 0

0B0A tC>7 6 5 4 3 2 1 0I>

&0B06 I> Start7 6 5 4 3 2 1 0

0B0B I>>7 6 5 4 3 2 1 0& t>>

0A05 Blk t>> Rev7 6 5 4 3 2 1 0

PF101 I>>>

PFC01 I<

0A06 Blk t>>>7 6 5 4 3 2 1 0

&1

0B0C t>>>

& t>>> 7 6 5 4 3 2 1 0PF201 I>>>

7 6 5 4 3 2 1 0Trip circuit breaker


tTRIP

tCLOSEReset

0A07 L Trip

7 6 5 4 3 2 1 00A08 L Close

7 6 5 4 3 2 1 00B0D CB Trip

7 6 5 4 3 2 1 00B0E CB Close


SD201

>= 1

>= 1

7 6 5 4 3 2 1 00A09 Ext. Trip

>=1>=1

7 6 5 4 3 2 1 00B0F CB FailtBF

RLY3


>= 1

LOG901

LOG201

I<Io<

Stage 3earth fault

0A03 Blk to>>>7 6 5 4 3 2 1 0

EF50

1

EF201

& to>>>0B05 to>>>7 6 5 4 3 2 1 0

Io>>>FWD

1

PF7

0

1 2/3

1

1


Figure 5b: Scheme logic diagram KCEG 152



SD801

0A0A Aux1tAux1

tAux2

7 6 5 4 3 2 1 0

3sec

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

F<

I<

Cold loadstart





PFD01

0B11 Aux2


Auxiliarytimers

7 6 5 4 3 2 1 0 >= 1

>= 1

LOG301

LOG401

Recorderstopped

&I<

Io<

tAux3

LOG40

1>= 1

LOG801

0A0C Aux37 6 5 4 3 2 1 0

LOG6

0

1

>= 10A0D Stg Grp 27 6 5 4 3 2 1 0

7 6 5 4 3 2 1 00B12 Aux3

LOG501

Remote set Grp2

Remote set Grp1

Set 1Reset 0

SD301

SD401


7 6 5 4 3 2 1 0

Plantstatusword

7 6 5 4 3 2 1 00D0F CB Open Ind

7 6 5 4 3 2 1 00A10 CB Bus 2

0A0E CB Closed Ind7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 00B15 Level 2

7 6 5 4 3 2 1 00B16 Level 3

0B14 Level 1

7 6 5 4 3 2 1 00B17 th Alarm

7 6 5 4 3 2 1 00B18 th Trip

>= 1

>= 1

Alarm

TripThermal

reset

PF0

01

7 6 5 4 3 2 1 00A11 Reset Ith

>= 1CBduty>

LOG001

CB(ops)>

7 6 5 4 3 2 1 00B19 CB Alarm

SD501

SD801

SD601

Recorderstopped

Reset trip flags

Resetdisturbance

recorder

Load shed level 1

Load shed level 2

Load shed level 3

SD

LOGF E D C B A 9 8 7 6 5 4 3 2 1 0

EF1

EF2

PF1

PF2F E D C B A 9 8 7 6 5 4 3 2 1 0 F E D C B A 9 8 7 6 5 4 3 2 1 0


Figure 6a: Scheme logic diagram KCEU 142/242 (continued in Figure 6b)

>=1

RLY7

LOGA01

I>

Io>

>=1

LOG701

>=1

Generate circuit breakermaintenance recordslatch red trip LED


7 6 5 4 3 2 1 0

Stage 3earth fault

Stage 1overcurrent

Startovercurrent

Stage 2overcurrent


PF5

FWD0

Stage 1earth fault

Startearth fault

Stage 2earth fault

& to>

Io>

& t>

EF30 EF4

0EF5

0

0A01 Blk to>7 6 5 4 3 2 1 0 0B03 to>

&FWD

REV

&

0B01 Io> Fwd Start

0A02 Blk to>>

EF40

EF10 & to>>

0B02 Io> Rev Start

0B04 to>>

Io>> FWD

0A03 Blk to>>>

EF50

EF2

1& to>>>

0B05 to>>>

Io>>> FWD EFE

1

0A04 Blk t>7 6 5 4 3 2 1 0

REV

0B09 tB>

0B08 tA>

0B0A tC>

&

&

&PF30

REV

FWD

I> PF4

0

PF5

0

PFF1

2 1

&PFF

1

2 1

0B06 I> Fwd Start

PFF1

2 1

PFF1

2 1

&0B07 I> Rev Start

0B0B t>>& t>>

0A05 Blk t>>PF1

0 PF4

FWDI>>>

PFC

I<0A06 Blk t>>>

&1

PF7

2

11

0B0C t>>>& t>>>

PFF

0

PFE

1REV

PF2

1I>>>

7 6 5 4 3 2 1 0TRIP CIRCUIT BREAKER

CLOSE CIRCUIT BREAKER

tTRIP

tCLOSEReset

0A07 L Trip

7 6 5 4 3 2 1 00A08 L Close

0B0D CB Trip

0B0E CB Close


SD20

>= 1

>= 1

0A09 Ext. Ttrip

>=1>=1 0B0F CB FailtBF

RLY3


>= 1

LOG9

1

LOG2

1

I<Io<

1

11

1

1

0

1

10

1 1 1

1

1

0

10

10

1

0

0

0 0

0

0

0

0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 07 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0



Figure 6b: Scheme logic diagram KCEU 142/242

F E D C B A 9 8 7 6 5 4 3 2 1 0

F E D C B A 9 8 7 6 5 4 3 2 1 0

F E D C B A 9 8 7 6 5 4 3 2 1 0

F E D C B A 9 8 7 6 5 4 3 2 1 0

0B10 Aux1


SD8

1

0A0A Aux1tAux1

tAux2

7 6 5 4 3 2 1 0

3sec

7 6 5 4 3 2 1 0

I<

Cold loadstart




0B11 Aux2


Auxiliarytimers>= 1

>= 1

LOG3

1

LOG4

1

Recorderstopped

&I<

Io<

tAux3

LOGB

1>= 1

LOG8

1

0A0C Aux3LOG6

1

>= 10A0D Stg Grp 2

7 6 5 4 3 2 1 00B12 Aux3

LOG5

1

Remote set Grp2

Remote set Grp1

Set 1Reset 0

SD3

1

SD4

1Change to

setting group 2

Plantstatusword

0D0F CB Open Ind

7 6 5 4 3 2 1 00A10 CB Bus 2

0A0E CB Closed Ind

0B17 th Alarm

0B18 th Trip

>= 1

>= 1

Alarm

TripThermal

reset

PF0

1

7 6 5 4 3 2 1 00A11 Reset Ith

>= 1CBduty>

LOG0

1

CB(ops)>

7 6 5 4 3 2 1 00B19 CB Alarm

SD5

1

SD8

1

SD6

1Recorderstopped

Reset trip flags

Resetdisturbance

recorder

SD

LOG

EF1

EF2

PF1

PF2

PF8

1

V< PF9

1&

>= 1

tV< 7 6 5 4 3 2 1 00B13 tV<

Undervoltage

0

0

0

0

0

0

0

0

0

0

0

0

0

0 0

0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

F E D C B A 9 8 7 6 5 4 3 2 1 0

F E D C B A 9 8 7 6 5 4 3 2 1 0



Relays

Service Manual

Appendix 3Connection Diagrams

SERVICE MANUAL R8551DKCGG 122, 142 Appendix 3KCEG 112, 142, 152, 242 ContentsKCEU 142, 242

CONTENTS

1. Connection diagrams for customising 12. Connection diagrams for relays as supplied 12

Figure 1: Typical application diagram: 2 phase overcurrent relay KCGG 122 1Figure 2: Typical application diagram: 3 phase overcurrent and earth fault

relay KCGG 142 01 2Figure 3: Typical application diagram: 3 phase overcurrent and earth fault

relay KCGG 142 02 3Figure 4: Typical application diagram: directional earth fault relay KCEG 112 4Figure 5: Typical application diagram: 3 phase overcurrent and directional

earth fault relay KCEG 142 5Figure 6: Typical application diagram: 3 phase overcurrent and directional earth

fault relay KCEG 152 6Figure 7: Typical application diagram: dual powered 3 phase overcurrent and

earth fault relay KCEG 242 7Figure 8: Typical application diagram: directional 3 phase overcurrent and

sensitive wattmetric earth fault relay KCEU 142 8Figure 9: Typical application diagram: directional 3 phase overcurrent and

sensitive wattmetric earth fault relay KCEU 242 9Figure 10: Typical application diagram: KCEU 142 showing connection for

broken delta VT winding 10Figure 11: Typical application diagram: KCEU 242 showing connection for

broken delta VT winding 11Figure 12: Typical application diagram: 2 phase overcurrent and relay KCCG 122 12Figure 13: Typical application diagram: 3 phase overcurrent and earth fault

relay KCGG 142 01 13Figure 14: Typical application diagram: 3 phase overcurrent and earth fault

relay KCGG 142 02 14Figure 15: Typical application diagram: directional earth fault relay KCEG 112 15Figure 16: Typical application diagram: 3 phase directional earth fault relay

KCEG 142 16Figure 17: Typical application diagram: 3 phase overcurrent and directional

earth fault relay KCEG 152 17Figure 18: Typical application diagram: dual powered 3 phase overcurrent and

directional earth fault relay KCEG 242 18Figure 19: Typical application diagram: directional 3 phase overcurrent and

sensitive wattmetric earth fault relay KCEU 142 19Figure 20: Typical application diagram: directional 3 phase overcurrent and

sensitive wattmetric earth fault relay KCEU 242 20Figure 21: Typical application diagram: KCEU 142 showing connection for

broken delta VT winding 21Figure 22: Typical application diagram: KCEU 242 showing connection for

broken delta VT winding 22


Section 1. CONNECTION DIAGRAMS FOR CUSTOMISING

Figu

re 1

: Ty

pica

l app

licat

ion

diag

ram

: 2 p

hase

ove

rcur

rent

rela

y KC

GG

122

1718

1920

2122

13 14 21 22 23 24 25 26 27 28 46L0

48L1

50L2

52(1

)Lo

gic

inpu

t com

mon

LP1

P2

S2S1

N

4 6Re

lay

heal

thy

3 5Re

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

AC/D

Csu

pply Vx

KCG

G 1

22

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

SCN

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)


Figu

re 2

: Ty

pica

l app

licat

ion

diag

ram

: 3 p

hase

ove

rcur

rent

and

ear

th fa

ult r

elay

KC

GG

142

01

13 14 21 22 23 24 25 26 27 28 46 48 50 52Lo

gic

inpu

t com

mon

(1)

AP1

P2

S2S1

B C

4 6Re

lay

heal

thy

3 5Re

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

7 8+4

8V fi

eld

volta

ge

AC/D

Csu

pply Vx

KCG

G 1

42 0

129 31

RL4

33 35RL

5

37 39RL

6

41 43RL

7

45L3

47L4

49L5

51L6

53L7

55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C

A

BPh

ase

rota

tion

1

Case

ear

thco

nnec

tion

54

KBu

s com

mun

icat

ions

por

t56

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

L0 L1 L2

SCN


Figu

re 3

: Ty

pica

l app

licat

ion

diag

ram

: 3 p

hase

ove

rcur

rent

and

ear

th fa

ult r

elay

KC

GG

142

02

13 14 21 22 23 24 25 26 27 28 46 48 50 52Lo

gic

inpu

t com

mon

AP1

P2

S2S1

B C

4 6Re

lay

heal

thy

3 5Re

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

7 8+4

8V fi

eld

volta

ge

AC/D

Csu

pply Vx

KCG

G 1

42 0

2

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C

A

BPh

ase

rota

tion

1

Case

ear

thco

nnec

tion

54

KBu

s com

mun

icat

ions

por

t56

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

L0 L1 L2

SCN


Figu

re 4

: Ty

pica

l app

licat

ion

diag

ram

: dire

ctio

nal e

arth

faul

t rel

ay K

CEG

112

13 14 21 22 23 24 25 26 27 28 46 48 50 52(1

)Lo

gic

inpu

t com

mon

AP1

P2

S2S1

B C

4 6Re

lay

heal

thy

3 5Re

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56

7 8+4

8V fi

eld

volta

ge

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

AC/D

Csu

pply Vx

KCEG

112

C N

BA

dn

da

19 20

Dire

ctio

n of

forw

ard

curre

nt fl

ow

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

L0 L1 L2

SCN


Figu

re 5

: Ty

pica

l app

licat

ion

diag

ram

: 3 p

hase

ove

rcur

rent

and

dire

ctio

nal e

arth

faul

t rel

ay K

CEG

142

13 14 21 22 23 24 25 26 27 28 46 48 50 52

AP1

P2

S2S1

B C

4 6Re

lay

heal

thy

3 5Re

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

AC/D

Csu

pply Vx

KCEG

142

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C N

BA

n

a

Dire

ction

of f

orw

ard

curre

nt fl

ow

bc

17 18 19 20

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1) L3 L4 L5 L6 L7L0 L1 L2

SCN


Figu

re 6

: Ty

pica

l app

licat

ion

diag

ram

: 3 p

hase

ove

rcur

rent

and

dire

ctio

nal e

arth

faul

t rel

ay K

CEG

152

KBu

s com

mun

icat

ions

por

t

13 14 21 22 23 24 25 26 27 28 46 48 50 52

AP1

P2

S2S1

B C

4 6Re

lay

heal

thy

3 5Re

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54 56 7 8+4

8V fi

eld

volta

ge

AC/D

Csu

pply Vx

KCEG

152

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

C N

BA

dn

da

Dire

ction

of f

orw

ard

curre

nt fl

ow

19 20

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1) L3 L4 L5 L6 L7L0 L1 L2

SCN


Figu

re 7

: Ty

pica

l app

licat

ion

diag

ram

: dua

l pow

ered

3 p

hase

ove

rcur

rent

and

ear

th fa

ult r

elay

KC

EG 2

42

AC/D

C su

pply

Vx L0

Logi

c in

put c

omm

on

Logi

c in

put c

omm

on (

1) L3 L4 L5 L6 L7L1 L2

13 14 21 22 23 24 25 26 27 28 46 48 50 52

AP1

P2

S2S1

B C

4 6Re

lay

faile

d

3 5Re

lay

heal

thy

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

KCEG

242

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)

9 10Su

pply

to tr

ip c

oil

Serie

sRE

G

C N

BA

n

aDire

ctio

n of

forw

ard

curre

nt fl

ow

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

17 18 19 20

bc

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

SCN


Figu

re 8

: Ty

pica

l app

licat

ion

diag

ram

: dire

ctio

nal 3

pha

se o

verc

urre

nt a

nd s

ensi

tive

wat

tmet

ric e

arth

faul

t rel

ay K

CEU

142

13 14 21 22 23 24 25 26 27 28 46 48 50 52

AP1

P2

S2S1

B C

4 6Re

lay

heal

thy

3 5Re

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

AC/D

Csu

pply Vx

KCEU

142

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C N

BA

n

a

Dire

ctio

n of

forw

ard

curre

nt fl

ow

17 18 19 20

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1) L3 L4 L5 L6 L7L0 L1 L2

SCN

P1P2

bc


Figu

re 9

: Ty

pica

l app

licat

ion

diag

ram

: dire

ctio

nal 3

pha

se o

verc

urre

nt a

nd s

ensi

tive

wat

tmet

ric e

arth

faul

t rel

ay K

CEU

242

46 48 50 52

AP1

P2

S2S1

B C

4 6Re

lay

heal

thy

3 5Re

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

KCEU

242

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C N

BA

Dire

ction

of f

orw

ard

curre

nt fl

ow

17 18 19 20

C

A

BPh

ase

rota

tion

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1) L3 L4 L5 L6 L7L0 L1 L2

SCN

P1P2

AC/D

Csu

pply

Vx

13 14 21 22 23 24 25 26 27 289 10

Supp

ly to

trip

coil

Serie

sRE

G

n

ab

c

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th


Figu

re 1

0: T

ypic

al a

pplic

atio

n di

agra

m: K

CEU

142

sho

win

g co

nnec

tion

for b

roke

n de

lta V

T w

indi

ng

13 14 21 22 23 24 25 26 27 28 46 48 50 52

AP1

P2

S2S1

B C

4 6Re

lay

heal

thy

3 5Re

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

AC/D

Csu

pply Vx

KCEU

142

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C N

BA

dn

da

Dire

ction

of f

orw

ard

curre

nt fl

ow

17 18 19 20

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1) L3 L4 L5 L6 L7L0 L1 L2

SCN

P1P2


Figu

re 1

1: T

ypic

al a

pplic

atio

n di

agra

m: K

CEU

242

sho

win

g co

nnec

tion

for b

roke

n de

lta V

T w

indi

ng

46 48 50 52

AP1

P2

S2S1

B C

4 6Re

lay

heal

thy

3 5Re

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

KCEU

242

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C N

BA

Dire

ction

of f

orw

ard

curre

nt fl

ow

17 18 19 20

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1) L3 L4 L5 L6 L7 L0 L1 L2

SCN

P1P2

AC/D

Csu

pply

Vx

13 14 21 22 23 24 25 26 27 289 10

Supp

ly to

trip

coil

Serie

sRE

G

dn

da


Section 2. CONNECTION DIAGRAMS FOR RELAYS ASSUPPLIED

Figu

re 1

2: T

ypic

al a

pplic

atio

n di

agra

m: 2

pha

se o

verc

urre

nt a

nd re

lay

KCC

G 1

22

13 14 21 22 23 24 25 26 27 28 46Ch

ange

setti

ng g

roup

L0

48Bl

ock

t>>/

to>>

L1

50Bl

ock

t>>>

/to>

>> L

2

52(1

)Lo

gic

inpu

t com

mon

LP1

P2

S2S1

N

4 6W

DRe

lay

heal

thy

3 5W

DRe

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

AC/D

Csu

pply Vx

KCG

G 1

22

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Star

t Io>

Star

t I>

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(t>/t

>>/t

>>>)

(to>/

to>>

/to>

>>/a

ux 1

)(t>

/t>>

/t>>

>)

SCN

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)


Figu

re 1

3: T

ypic

al a

pplic

atio

n di

agra

m: 3

pha

se o

verc

urre

nt a

nd e

arth

faul

t rel

ay K

CG

G 1

42 0

1

13 14 21 22 23 24 25 26 27 28 46 48 50 52Lo

gic

inpu

t com

mon

(1)

AP1

P2

S2S1

B C

4 6W

DRe

lay

heal

thy

3 5W

DRe

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

7 8+4

8V fi

eld

volta

ge

AC/D

Csu

pply Vx

KCG

G 1

42 0

129 31

RL4

33 35RL

5

37 39RL

6

41 43RL

7

45Ex

tern

al tr

ip L

3

47In

itiat

e au

xilia

ry ti

mer

2 L

4

49In

itiat

e au

xilia

ry ti

mer

3 L

5

51CB

clo

sed

indi

catio

n L6

53CB

ope

n in

dica

tion

L7

55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C

A

BPh

ase

rota

tion

1

Case

ear

thco

nnec

tion

54

KBu

s com

mun

icat

ions

por

t56

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

Chan

ge se

tting

gro

up L

0

Bloc

k t>

>/to

>> L

1

Bloc

k t>

>>/t

o>>>

L2

Star

t Io>

Star

t I>

thAl

arm

/CB

alar

m/C

B fa

il

CB fa

il/ba

cktri

p

Cont

rol C

B clo

se

Cont

rol C

B tri

p

SCN

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(t>/t

>>/t

>>>)

(to>/

to>>

/to>

>>/a

ux 1

)(t>

/t>>

/t>>

>)


Figu

re 1

4: T

ypic

al a

pplic

atio

n di

agra

m: 3

pha

se o

verc

urre

nt a

nd e

arth

faul

t rel

ay K

CG

G 1

42 0

2

13 14 21 22 23 24 25 26 27 28 46 48 50 52Lo

gic

inpu

t com

mon

AP1

P2

S2S1

B C

4 6W

DRe

lay

heal

thy

3 5W

DRe

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

7 8+4

8V fi

eld

volta

ge

AC/D

Csu

pply Vx

KCG

G 1

42 0

2

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C

A

BPh

ase

rota

tion

1

Case

ear

thco

nnec

tion

54

KBu

s com

mun

icat

ions

por

t56

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

Chan

ge se

tting

gro

up L

0

Bloc

k t>

>/to

>> L

1

Bloc

k t>

>>/t

o>>>

L2

Star

t Io>

Star

t I>

SCN

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(t>/t

>>/t

>>>)

(to>/

to>>

/to>

>>/a

ux 1

)(t>

/t>>

/t>>

>)


Figu

re 1

5: T

ypic

al a

pplic

atio

n di

agra

m: d

irect

iona

l ear

th fa

ult r

elay

KC

EG 1

12

13 14 21 22 23 24 25 26 27 28 46 48 50 52(1

)Lo

gic

inpu

t com

mon

AP1

P2

S2S1

B C

4 6W

DRe

lay

heal

thy

3 5W

DRe

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56

7 8+4

8V fi

eld

volta

ge

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

AC/D

Csu

pply Vx

KCEG

112

C N

BA

dn

da

19 20

Dire

ctio

n of

forw

ard

curre

nt fl

ow

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Chan

ge se

tting

gro

up L

0

Bloc

k to

>> L

1

Bloc

k to

>>>

L2

Star

t (Io

>FW

D)

Star

t (Io

>REV

)

SCN

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(to>/

to>>

/to>

>>/a

ux 1

)


Figu

re 1

6: T

ypic

al a

pplic

atio

n di

agra

m: 3

pha

se d

irect

iona

l ear

th fa

ult r

elay

KC

EG 1

42

13 14 21 22 23 24 25 26 27 28 46 48 50 52

AP1

P2

S2S1

B C

4 6W

DRe

lay

heal

thy

3 5W

DRe

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

AC/D

Csu

pply Vx

KCEG

142

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C N

BA

n

a

Dire

ction

of f

orw

ard

curre

nt fl

ow

bc

17 18 19 20

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1)

Exte

rnal

trip

L3

Initi

ate

auxi

liary

tim

er 2

L4

Initi

ate

auxi

liary

tim

er 3

L5

CB c

lose

d in

dica

tion

L6

CB o

pen

indi

catio

n L7

Chan

ge se

tting

gro

up L

0

Bloc

k t>

>/to

>> L

1

Bloc

k t>

>>/t

o>>>

L2

Star

t (Io

> FW

D/I>

FW

D)

Star

t (Io

> RE

V/I>

REV

)

thAl

arm

/CB

alar

m/C

B fa

il

CB fa

il/ba

cktri

p

Cont

rol C

B clo

se

Cont

rol C

B tri

p

SCN

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(t>/t

>>/t

>>>)

(to>/

to>>

/to>

>>/a

ux 1

)(th

Trip

/t>/

t>>/

t>>>

)


Figu

re 1

7: T

ypic

al a

pplic

atio

n di

agra

m: 3

pha

se o

verc

urre

nt a

nd d

irect

iona

l ear

th fa

ult r

elay

KC

EG 1

52

KBu

s com

mun

icat

ions

por

t

13 14 21 22 23 24 25 26 27 28 46 48 50 52

AP1

P2

S2S1

B C

4 6W

DRe

lay

heal

thy

3 5W

DRe

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54 56 7 8+4

8V fi

eld

volta

ge

AC/D

Csu

pply Vx

KCEG

152

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

C N

BA

dn

da

Dire

ctio

n of

forw

ard

curre

nt fl

ow

19 20

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1)

Exte

rnal

trip

L3

Initi

ate

auxi

liary

tim

er 3

L4

Initi

ate

auxi

liary

tim

er 3

L5

CB c

lose

d in

dica

tion

L6

CB o

pen

indi

catio

n L7

Chan

ge se

tting

gro

up L

0

Bloc

k t>

>/to

>>

L1

Bloc

k t>

>>/t

o>>>

L2

Star

t (Io

>FW

D)

Star

t (Io

>REV

)

thAl

arm

/CB

alar

m/C

B fa

il

CB fa

il/ba

cktri

p

Cont

rol C

B clo

se

Cont

rol C

B tri

p

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(t>/t

>>/t

>>>)

(to>/

to>>

/to>

>>/a

ux 1

)(th

Trip

/t>/

t>>/

t>>>

)

SCN


Figu

re 1

8: T

ypic

al a

pplic

atio

n di

agra

m: d

ual p

ower

ed 3

pha

se o

verc

urre

nt a

nd d

irect

iona

l ear

th fa

ult r

elay

KC

EG 2

42

AC/D

C su

pply

Vx

Chan

ge se

tting

gro

up L

0

Star

t (Io

>FW

D/I>

FWD)

Star

t (Io

>REV

/I>R

EV)

thAl

arm

/CB

alar

m/C

B fa

il

CB fa

il/ba

cktri

p

Cont

rol C

B clo

se

Cont

rol C

B tri

p

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(t>/t

>>/t

>>>)

(to>/

to>>

/to>

>>/a

ux 1

)(th

Trip

/t>/

t>>/

t>>>

)

Logi

c in

put c

omm

on

Logi

c in

put c

omm

on (

1)

Exte

rnal

trip

L3

Initi

ate

auxi

liary

tim

er 3

L4

Initi

ate

auxi

liary

tim

er 3

L5

CB c

lose

d in

dica

tion

L6

CB o

pen

indi

catio

n L7

Bloc

k t>

>/to

>>

L1

Bloc

k t>

>>/t

o>>>

L2

13 14 21 22 23 24 25 26 27 28 46 48 50 52

AP1

P2

S2S1

B C

4 6W

DRe

lay

faile

d

3 5W

DRe

lay

heal

thy

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

KCEG

242

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)

9 10Su

pply

to tr

ip c

oil

Serie

sRE

G

C N

BA

n

aDire

ctio

n of

forw

ard

curre

nt fl

ow

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

17 18 19 20

bc

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

SCN


Figu

re 1

9: T

ypic

al a

pplic

atio

n di

agra

m: d

irect

iona

l 3 p

hase

ove

rcur

rent

and

sen

sitiv

e w

attm

etric

ear

th fa

ult r

elay

KC

EU 1

42

13 14 21 22 23 24 25 26 27 28 46 48 50 52

AP1

P2

S2S1

B C

4 6W

DRe

lay

heal

thy

3 5W

DRe

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

AC/D

Csu

pply Vx

KCEU

142

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C N

BA

n

a

Dire

ctio

n of

forw

ard

curre

nt fl

ow

17 18 19 20

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1)

Exte

rnal

trip

L3

Initi

ate

auxi

liary

tim

er 2

L4

Initi

ate

auxi

liary

tim

er 3

L5

CB c

lose

d in

dica

tion

L6

CB o

pen

indi

catio

n L7

Chan

ge se

tting

gro

up L

0

Bloc

k t>

>/to

>> L

1

Bloc

k t>

>>/t

o>>>

L2

Star

t (Io

> FW

D/I>

FW

D)

Star

t (Io

> RE

V/I>

REV

)

thAl

arm

/CB

alar

m/C

B fa

il

CB fa

il/ba

cktri

p

Cont

rol C

B clo

se

Cont

rol C

B tri

p

SCN

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(t>/t

>>/t

>>>)

(to>/

to>>

/to>

>>/a

ux 1

)(th

Trip

/t>/

t>>/

t>>>

)

P1P2

bc


Figu

re 2

0: T

ypic

al a

pplic

atio

n di

agra

m: d

irect

iona

l 3 p

hase

ove

rcur

rent

and

sen

sitiv

e w

attm

etric

ear

th fa

ult r

elay

KC

EU 2

42

46 48 50 52

AP1

P2

S2S1

B C

4 6W

DRe

lay

heal

thy

3 5W

DRe

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

KCEU

242

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C N

BA

Dire

ctio

n of

forw

ard

curre

nt fl

ow

17 18 19 20

C

A

BPh

ase

rota

tion

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1)

Exte

rnal

trip

L3

Initi

ate

auxi

liary

tim

er 2

L4

Initi

ate

auxi

liary

tim

er 3

L5

CB c

lose

d in

dica

tion

L6

CB o

pen

indi

catio

n L7

Chan

ge se

tting

gro

up L

0

Bloc

k t>

>/to

>> L

1

Bloc

k t>

>>/t

o>>>

L2

Star

t (Io

> FW

D/I>

FW

D)

Star

t (Io

> RE

V/I>

REV

)

thAl

arm

/CB

alar

m/C

B fa

il

CB fa

il/ba

cktri

p

Cont

rol C

B clo

se

Cont

rol C

B tri

p

SCN

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(t>/t

>>/t

>>>)

(to>/

to>>

/to>

>>/a

ux 1

)(th

Trip

/t>/

t>>/

t>>>

)

P1P2

AC/D

Csu

pply

Vx

13 14 21 22 23 24 25 26 27 289 10

Supp

ly to

trip

coil

Serie

sRE

G

n

ab

c

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th


Figu

re 2

1: T

ypic

al a

pplic

atio

n di

agra

m: K

CEU

142

sho

win

g co

nnec

tion

for b

roke

n de

lta V

T w

indi

ng

13 14 21 22 23 24 25 26 27 28 46 48 50 52

AP1

P2

S2S1

B C

4 6W

DRe

lay

heal

thy

3 5W

DRe

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54

KBu

s com

mun

icat

ions

por

t56 7 8

+48V

fiel

d vo

ltage

AC/D

Csu

pply Vx

KCEU

142

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C N

BA

dn

da

Dire

ctio

n of

forw

ard

curre

nt fl

ow

17 18 19 20

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1)

Exte

rnal

trip

L3

Initi

ate

auxi

liary

tim

er 2

L4

Initi

ate

auxi

liary

tim

er 3

L5

CB c

lose

d in

dica

tion

L6

CB o

pen

indi

catio

n L7

Chan

ge se

tting

gro

up L

0

Bloc

k t>

>/to

>> L

1

Bloc

k t>

>>/t

o>>>

L2

Star

t (Io

> FW

D/I>

FW

D)

Star

t (Io

> RE

V/I>

REV

)

thAl

arm

/CB

alar

m/C

B fa

il

CB fa

il/ba

cktri

p

Cont

rol C

B clo

se

Cont

rol C

B tri

p

SCN

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(t>/t

>>/t

>>>)

(to>/

to>>

/to>

>>/a

ux 1

)(th

Trip

/t>/

t>>/

t>>>

)

P1P2


Figu

re 2

2: T

ypic

al a

pplic

atio

n di

agra

m: K

CEU

242

sho

win

g co

nnec

tion

for b

roke

n de

lta V

T w

indi

ng

KBu

s com

mun

icat

ions

por

t

46 48 50 52

AP1

P2

S2S1

B C

4 6W

DRe

lay

heal

thy

3 5W

DRe

lay

faile

d

30 32RL

0

34 36RL

1

38 40RL

2

42 44RL

3

54 56 7 8+4

8V fi

eld

volta

ge

KCEU

242

29 31RL

4

33 35RL

5

37 39RL

6

41 43RL

7

45 47 49 51 53 55(2

)Lo

gic

inpu

t com

mon

Not

es: (a)

CT sh

ortin

g lin

ks m

ake

befo

re (b

) and

(c) d

iscon

nect.

(b)

Shor

t ter

min

als b

reak

bef

ore

(c).

(c)

Long

term

inal

(d)

Pin

term

inal

(pcb

type

).

(1)

CT c

onne

ction

s are

typi

cal o

nly.

(2)

Earth

con

necti

ons a

re ty

pica

l onl

y.(3

)

C N

BA

Dire

ction

of f

orw

ard

curre

nt fl

ow

17 18 19 20

C

A

BPh

ase

rota

tion

3 54 6

1 7 98 10

31 3332 34

29 35 3736 3830

3940

4142

4344

4546

4748

4950

5152

5354

5556

1314

1718

1920

2122

2324

2526

2728

SCN

Mod

ule

term

inal

blo

cks

view

ed fr

om re

ar(w

ith in

tegr

al c

ase

earth

stra

p)

Case

ear

th

1

Case

ear

thco

nnec

tion

Logi

c in

put c

omm

on (

1)

Exte

rnal

trip

L3

Initi

ate

auxi

liary

tim

er 2

L4

Initi

ate

auxi

liary

tim

er 3

L5

CB c

lose

d in

dica

tion

L6

CB o

pen

indi

catio

n L7

Chan

ge se

tting

gro

up L

0

Bloc

k t>

>/to

>> L

1

Bloc

k t>

>>/t

o>>>

L2

Star

t (Io

> FW

D/I>

FW

D)

Star

t (Io

> RE

V/I>

REV

)

thAl

arm

/CB

alar

m/C

B fa

il

CB fa

il/ba

cktri

p

Cont

rol C

B clo

se

Cont

rol C

B tri

p

SCN

AR in

itiat

e

Trip

(to>/

to>>

/to>

>>)

(t>/t

>>/t

>>>)

(to>/

to>>

/to>

>>/a

ux 1

)(th

Trip

/t>/

t>>/

t>>>

)

P1P2

AC/D

Csu

pply

Vx

13 14 21 22 23 24 25 26 27 289 10

Supp

ly to

trip

coil

Serie

sRE

G

dn

da



Relays

Service Manual

Appendix 4Commissioning Test Record

SERVICE MANUAL R8551CKCGG 122, 142 Appendix 4KCEG 112, 142, 152, 242 ContentsKCEU 142, 242

1. COMMISSIONING TEST RECORD 12. SETTING RECORD 6

REPAIR FORM 11

SERVICE MANUAL R8551CKCGG 122, 142 Appendix 4KCEG 112 142, 152, 242 Page 1 of 12KCEU 142, 242

Section 1. COMMISSIONING TEST RECORD

Date

Station Circuit

System Frequency

Front plate information

Multifunctional overcurrent relay type KC________

Model number

Serial number

Auxiliary Voltage Vx

Polarising Voltage Vn

Rated Current In

*Delete as appropriate

4 Product checks

4.1 With the relay de-energised

4.1.1 Visual inspection

Module and case damaged? Yes/No*

Model numbers on case and front plate match? Yes/No*

Serial numbers on case and front plate match? Yes/No*

Rating information correct for installation? Yes/No*

All current transformer shorting switches closed? Yes/No*

Case earth installed? Yes/No*

4.1.2 Insulation resistance correct? Yes/No/Not Tested*

4.1.3 External wiring

Wiring checked against diagram? Yes/No*

Test block connections checked? Yes/No/na*



With auxiliary supply off Terminals 3 and 5 Open/Closed*

Terminals 4 and 6 Open/Closed*

4.1.5 Auxiliary supply ______V ac/dc*

4.2 With the relay energised


With auxiliary supply on Terminals 3 and 5 Open/Closed*

Terminals 4 and 6 Open/Closed*

4.2.2 Light emitting diodes

Relay healthy (green) LED working? Yes/No*

Alarm (yellow) LED working? Yes/No*

Trip (red) LED working? Yes/No*

4.2.3 Liquid crystal display

All pixels working? Yes/No*

Backlight switches on and off? Yes/No*

4.2.4 Field supply voltage

Relay energised from auxiliary supply ______V dc

Relay energised from line current transformers(Section 4.2.11 – KCEG 242 and KCEU 242 only) ______V dc/na*

4.2.5 Capacitor trip voltage

Relay energised from auxiliary supply ______V dc

Relay energised from line current transformers(Section 4.2.11 – KCEG 242 and KCEU 242 only) ______V dc/na*

4.2.6 Input opto-isolators

Input L0 working? Yes/No*



Input L3 working? Yes/No/na*






4.2.7 Output relays

Output RL0 working? Yes/No*




Output RL4 working? Yes/No/na*




4.2.8 K-Bus communications working? Yes/No/na*

4.2.9 Current inputs

CT ratio (phase currents) _______:1A

CT ratio (Zero sequence current) _______:1A/na*

Input CT Applied value Relay value

Ia _______A/na* _______A

Ib _______A/na* _______A

Ic _______A/na* _______A

Io _______A/na* _______A

4.2.10 Voltage inputs (KCEG and KCEU relays only)

VT Ratio (phase voltages) _______:1V/na*

VT Ratio (residual voltage) _______:1V/na*

Input VT Applied value Relay value

Va _______V/na* _______V

Vb _______V/na* _______V

Vc _______V/na* _______V

Vo _______V/na* _______V

4.2.11 Energisation from line current transformers(KCEG 242 and KCEU 242 relays only)

Record results under Sections 4.2.4 and 4.2.5


5 Setting checks

5.1 Customer’s settings applied? Yes/No*

If settings applied using a portable computerand software, which software and version was used? ____________________

5.2 Settings on relay verified? Yes/No*

5.3 Protection function timing tested? Yes/No*

Function tested t>/to>

Polarising voltage (KCEG/KCEU relays only) _________V/na*

Characteristic angle (KCEG/KCEU relays only) _________°/na*

Operating boundary 1 (KCEG/KCEU relays only) _________°/na*

Operating boundary 2 (KCEG/KCEU relays only) _________°/na*

Applied current _________A

Expected nominal operating time _________s

Actual operating time _________s

6 On-load checks

Test wiring removed? Yes/No/na*

Disturbed customer wiring re-checked? Yes/No/na*

On-load test performed? Yes/No*

6.1.1 VT wiring checked? (KCEG/KCEU relays only) Yes/No/na*

VT ratio (Phase voltages) ____:1V/na*

VT ratio (Residual voltage) ____:1V/na*

Phase rotation correct Yes/No*

Voltages: Applied value Relay value

Va _______V/na* _______V

Vb _______V/na* _______V

Vc _______V/na* _______V

Vo _______V/na* _______V


6.1.2 CT wiring checked? Yes/No/na*

and 6.2 CT ratio (Phase currents) ____:1A/na*

CT ratio (Earth fault currents) ____:1A/na*

Currents: Applied value Relay value

Ia _______A/na* _______A

Ib _______A/na* _______A

Ic _______A/na* _______A

Io _______A/na* _______A

7 Final checks

Test wiring removed? Yes/No/na*

Disturbed customer wiring re-checked? Yes/No/na*

Circuit breaker operations counter set/reset? Set/Reset/na*

If set, value counter set to: ________/na*

Current squared counters set/reset? Set/Reset/na*

If set, value counter set to: (‘A’ phase) ________A2/na*

(‘B’ phase) ________A2/na*

(‘C’ phase) ________A2/na*

Event records reset? Yes/No*

Fault records reset? Yes/No*

Disturbance records reset Yes/No*

Alarms reset? Yes/No*

LEDs reset? Yes/No*

Commissioning Engineer

Date

Customer Witness

Date


Section 2. SETTING RECORD

Date Engineer

Station Date

Circuit System Frequency

Front plate information

Multifunctional overcurrent relay type KC________

Model number

Serial number

Auxiliary Voltage Vx

Polarising Voltage Vn

Rated Current In

0000SYSTEM DATA F E D C B A 9 8 7 6 5 4 3 2 1 0

0002 Password

0003 SD Links 0 0 0 0 0 0 0 0

0004 Description

0005 Plant

0006 Model

0008 Serial No.

0009 Frequency

000A Comms Level

000B Rly Address

0011 Software Ref.


0500 EARTH FLT 1 F E D C B A 9 8 7 6 5 4 3 2 1 0

0501 EF Links 0 0 0 0 0 0 0 0 0

0502 CT Ratio

0503 VT Ratio

0504 Curve

0505 Io>

0506 to/TMS

0507 to/DT

0508 toRESET

0509 Io>>

050A to>>

050B Io>>>

050C to>>>

050D Char Angle

050E Io<

050F Vop>

0600 PHASE FLT 1 F E D C B A 9 8 7 6 5 4 3 2 1 00601 PF Links

0602 CT Ratio

0603 VT Ratio

0604 Curve

0605 I>

0606 t/TMS

0607 t/DT

0608 tRESET

0609 I>>

060A t>>

060B I>>>

060C t>>>

060D Char Angle

060E I<

060F V<

0610 tV<

0611 F<

0612 th> Alarm

0613 Ith> Trip

0614 TC


0700 EARTH FLT 2 F E D C B A 9 8 7 6 5 4 3 2 1 00701 EF Links 0 0 0 0 0 0 0 0 00702 CT Ratio0703 VT Ratio0704 Curve0705 Io>0706 to/TMS0707 to/DT0708 toRESET0709 Io>>070A to>>070B Io>>>070C to>>>070D Char Angle070E Io<070F Vop>0710 Po>

0800 PHASE FLT 2 F E D C B A 9 8 7 6 5 4 3 2 1 0

0801 PF Links0802 CT Ratio0803 VT Ratio0804 Curve0805 I>0806 t/TMS0807 t/DT0808 tRESET0809 I>>080A t>>080B I>>>080C t>>>080D Char Angle080E I<080F V<0810 tV<0811 F<0812 th> Alarm0813 Ith> Trip0814 TC


0900 LOGIC F E D C B A 9 8 7 6 5 4 3 2 1 0

0901 LOG Links 0 0 0 0

0902 tBF

0903 tAUX1

0904 tAUX2

0905 tAUX3

0906 tTRIP

0907 tCLOSE

0908 CB ops>

0909 CB duty>

090F Display

0A00 INPUT MASKS F E D C B A 9 8 7 6 5 4 3 2 1 0

0A01 Blk to> 0 0 0 0 0 0 0 0

0A02 Blk to>> 0 0 0 0 0 0 0 0

0A03 Blk to>>> 0 0 0 0 0 0 0 0

0A04 Blk t> 0 0 0 0 0 0 0 0

0A05 Blk t>> 0 0 0 0 0 0 0 0

0A06 Blk t>>> 0 0 0 0 0 0 0 0

0A07 L Trip 0 0 0 0 0 0 0 0

0A08 L Close 0 0 0 0 0 0 0 0

0A09 Ext Trip 0 0 0 0 0 0 0 0

0A0A Aux 1 0 0 0 0 0 0 0 0

0A0B Aux 2 0 0 0 0 0 0 0 0

0A0C Aux 3 0 0 0 0 0 0 0 0

0A0D Set Grp 2 0 0 0 0 0 0 0 0

0A0E CB Closed 0 0 0 0 0 0 0 0

0A0F CB Open 0 0 0 0 0 0 0 0

0A10 Bus2 0 0 0 0 0 0 0 0

0A11 Reset Ith 0 0 0 0 0 0 0 0


0B00 RELAY MASKS F E D C B A 9 8 7 6 5 4 3 2 1 0

0B01 Io> Fwd 0 0 0 0 0 0 0 0

0B02 Io> Rev 0 0 0 0 0 0 0 0

0B03 to> 0 0 0 0 0 0 0 0

0B04 to>> 0 0 0 0 0 0 0 0

0B05 to>>> 0 0 0 0 0 0 0 0

0B06 I>Fwd 0 0 0 0 0 0 0 0

0B07 I>Rev 0 0 0 0 0 0 0 0

0B08 tA> 0 0 0 0 0 0 0 0

0B09 tB> 0 0 0 0 0 0 0 0

0B0A tC> 0 0 0 0 0 0 0 0

0B0B t>> 0 0 0 0 0 0 0 0

0B0C t>>> 0 0 0 0 0 0 0 0

0B0D CB Trip 0 0 0 0 0 0 0 0

0B0E CB Close 0 0 0 0 0 0 0 0

0B0F CB Fail 0 0 0 0 0 0 0 0

0B10 Aux 1 0 0 0 0 0 0 0 0

0B11 Aux 2 0 0 0 0 0 0 0 0

0B12 Aux 3 0 0 0 0 0 0 0 0

0B13 tV< 0 0 0 0 0 0 0 0

0B14 Level 1 0 0 0 0 0 0 0 0

0B15 Level 2 0 0 0 0 0 0 0 0

0B16 Level 3 0 0 0 0 0 0 0 0

0B17 thAlarm 0 0 0 0 0 0 0 0

0B18 thTrip 0 0 0 0 0 0 0 0

0B19 CB Alarm 0 0 0 0 0 0 0 0

0C00 RECORDER F E D C B A 9 8 7 6 5 4 3 2 1 0

0C01 Control

0C02 Capture

0C03 Post Trigger

0C04 Logic Trig

0C05 Relay Trig


continued overleaf

REPAIR FORM

Please complete this form and return it to ALSTOM T&D Protection & Control Limited with theequipment to be repaired. This form may also be used in the case of application queries.

ALSTOM T&D Protection & Control LimitedSt. Leonards WorksStaffordST17 4LX,England

For: After Sales Service Department

Customer Ref: ________________________ Model No: __________________

ALSTOM Contract Ref: ________________________ Serial No: __________________

Date: ________________________

1. What parameters were in use at the time the fault occurred?

AC volts _____________ Main VT/Test set

DC volts _____________ Battery/Power supply

AC current _____________ Main CT/Test set

Frequency _____________

2. Which type of test was being used? ____________________________________________

3. Were all the external components fitted where required? Yes/No(Delete as appropriate.)

4. List the relay settings being used

____________________________________________________________________________

____________________________________________________________________________

____________________________________________________________________________

5. What did you expect to happen?

____________________________________________________________________________

____________________________________________________________________________

____________________________________________________________________________

____________________________________________________________________________


6. What did happen?

____________________________________________________________________________

____________________________________________________________________________

____________________________________________________________________________

____________________________________________________________________________

7. When did the fault occur?

Instant Yes/No Intermittent Yes/No

Time delayed Yes/No (Delete as appropriate).

By how long? ___________

8. What indications if any did the relay show?

____________________________________________________________________________

____________________________________________________________________________

____________________________________________________________________________

9. Was there any visual damage?

____________________________________________________________________________

____________________________________________________________________________

____________________________________________________________________________

10. Any other remarks which may be useful:

____________________________________________________________________________

____________________________________________________________________________

____________________________________________________________________________

______________________________________ _______________________________________Signature Title

______________________________________ _______________________________________Name (in capitals) Company name

A L S T O M T & D P r o t e c t i o n & C o n t r o l L t d St Leonards Works, Stafford, ST17 4LX EnglandTel: 44 (0) 1785 223251 Fax: 44 (0) 1785 212232 Email: [email protected] Internet: www.alstom.com

©1999 ALSTOM T&D Protection & Control Ltd

Our policy is one of continuous product development and the right is reserved to supply equipment which may vary from that described.

Publication R8551D 0899 Printed in England.

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