technical specifications for electrical work

7/28/2019 Technical Specifications for Electrical Work

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Scope:

Design, Supply, Integration, Delivery, Testing and Commissioning of Compartmentalized LTPanel Boards in accordance with this specification.

Note: Integration includes supply of materials like Meters, CTs, Bus bars, Bus Supports,

Indicating Lamps, Metering Fuses, PLC, etc.,

Related Items not included:

Foundations Hardwares

External connections to the equipments.

Conformance to Standards:

The Tenderer shall control the quality of items and services to meet the requirements of thisspecification, applicable codes and standards and other procurement documents.

Standards:

The Panel Boards shall comply with the latest issue of the following standards

IS 8623 General requirement for factory built assemblies upto 1000 Volts.

IS 10118 Code of Practice for selection and maintenance of Switchgear and

Control gear.

IS 13947-2 A.C. Circuit breaker requirements Voltage not exceeding 1000Vs

Part I & II, Sec 1 and IEC 60947 part I & III

IS 2147 Degree of protection provided by enclosures for low voltage Switchgear

and Control gear

IS 2705 Specification for current transformers

IS 1248 Specification for direct acting electrical indicating instruments.

IS 3156 Voltage transformers

IS 3231 Relays

IS 13703 Specification for HRC cartridge fuse links upto 650 Volts.

TECHNICAL SPECIFICATIONS OF LT PANEL BOARDS


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IS 6875 Control Switches / Push Buttons

IS 11353 Marketing and identification of conductors and apparatus

IS 13947 part I & II Moulded Case Circuit Breaker

IS 375 Arrangement for Busbars main connection and accessories

IS 6005 Code of practice for phosphating Iron and Steel

IS 5082 Wrought Aluminium & Aluminium Alloy for Electrical Purposes

General:

The LT Panels shall be of, Metal enclosed, indoor, floor mounted freestanding type.

Made up of the requisite vertical sections, which when coupled together shall formcontinuous dead front switchboards.

Provide dust and vermin proof design.

Readily extensible on both sides by the addition of vertical sections after removal ofthe end covers.

The panels shall be constructed only of materials capable of withstanding themechanical, electrical and thermal stresses as well as the effects of humidity, whichare likely to be encountered in normal service.

Each vertical section shall comprise: -

A front-framed structure of rolled/folded sheet steel / Angle channel section, ofminimum 14SWG thickness, rigidly bolted / welded together. This structure shallhouse the components contributing to the major weight of the equipment, such ascircuit breaker cassettes, MCCBs, main horizontal busbars, vertical risers and otherfront mounted accessories.

The structure shall be mounted on a rigid base frame of folded sheet steel ofminimum 3mm thickness and 75mm height. The design shall ensure that weight ofthe components is adequately supported without deformation or loss of alignmentduring transit.

The design shall ensure generous availability of space for installation andmaintenance of cabling, and adequate safety for working in vertical section withoutcoming into accidental contact with live parts in an adjacent section.


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Front doors and rear covers fitted with dust excluding synthetic rubber gaskets withfasteners designed to ensure proper compressions of gaskets. When covers areprovided in place of doors, generous overlap shall be assured between sheet steelsurface with closely spaced fasteners to preclude the entry of dust.

The height of the panel should not be more than 2100mm.The total depth of thepanel should be adequate to cater for proper cabling space and shall not exceed1200mm for ACB sections.

Doors shall be minimum 14SWG sheet steel. Sheet steel shrouds and partitions shallbe of minimum 16SWG thickness. All sheet steelwork forming the exterior ofswitchboards shall be smoothly finished, leveled and free from flaws. The cornersshould be rounded.

Apparatus forming part of the panel shall have the following recommended minimumclearances for un-insulated bus bars are should as per relevant IS codes

All insulating material used in the construction of the equipment shall be of non-hygroscopic material, duly treated to withstand the effects of high humidity, hightemperature tropical ambient service conditions.

Metallic/insulated barriers shall be provided between adjacent sections to ensureprevention of accidental contact.

All doors/covers providing access to live power equipments circuits shall be providedtool operated fasteners to prevent unauthorized access.

Provision shall be made for permanently earthing the frames and other metal part ofthe switchgear by two independent connections.

Operating devices shall be incorporated only in the front of the switchgear. No handleneeding manual operation shall be located less than 450mm and not higher than1800mm above ground level.

BUSBARS

The bus bars shall be air insulated and made of high conductivity, high strength,

A current density of not less than 800 A /Sq.inch. shall be provided for COPPERSbusbars/Interconnect, Cable connectors etc. For Panel , the size of the busbars shallbe designed on the basis of a short circuit rating as of incomer feeder.

The bus bars shall be mounted suitably on non-hygroscopic SMC / FRP supportsrigidly fixes to the panel and the supports shall be fixed to the main frame withoutaffecting the clearance structure as per IS and should also be capable ofwithstanding the stress of electrical fault.

99.99% Purity Electrolytic grade ALUMINIUM.


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Large clearances and Creepage distances shall be provided on the busbars systemto minimize the possibility of a fault.

High tensile bolts and spring washers shall be minimized the possibility of a fault.

Connections from the main busbars to functional circuits shall be arranged andsupported so as to withstand without any damage or deformation the thermal anddynamic stresses due to short circuit currents.

Busbars shall be color coded for easy identification of individual phases and neutralwith heat shrinkable PVC sleeves.

The main busbars shall have uniform current ratings through their length. The currentrating of the neutral shall be half that of the phase busbars throughout the length ofthe switchboard. However for the UPS Panels, the Neutral Busbars shall be Doublethe size of Phase busbars. Removable neutral links shall be provided on feeders topermit isolation of the neutral busbar.

The busbar and supports shall be capable of withstanding Short circuit current as ofthe incomers in panel .Only zinc passivated or cadmium plated high tensile strengthsteel bolts, nuts and washers shall be used for all bus bar joints and supports. All busbar supports shall be SMC / FRP only.

All bus bars shall be sleeved with colour coded heat shrinkable sleeves with theexception of joints . Red, yellow and blue colour shall be used for Phase busbarsand Black colour shall be used for neutral bus bars.

The Busbars shall be capable of withstanding rated capacity without any deration at

55

C over 45C Ambient.

The Bus Bar to switch gear terminal connections shall be with rectangular COPPERBar with current density as desired for Bus Bars and shall be rigidly fixed with Bus &Switch gear ends with high tensile Bolts with spring washers & flat washers withnecessary full nut and locking nuts to have proper contact area.

The Inter connections also shall be sleeved wit h heat shrinkable OVC sleeves withappropriate colour coding with the exception of joints.

The inter connections between Bus & Switch gear terminals shall be provided withnecessary FRP / SMC support to avoid strain to the switch gear terminal .

The outgoing shall be provided with suitable & Adequately rated connections toreceive the cables / Bus duct terminal connections .The connection should besupported to main frame in such a way that strains of cable connections shall nottransmitted to the switch gear terminal & to withstand the electrical stress.

These connections also shall be sleeved in the colour coded PVC heat shrinkablesleeves with the exception of joints.


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Wiring and Cable Terminations:

Inside the switch boards the wiring for power, control, signaling, protection andinstrument circuits shall be done with PVC Insulated FRLS multistrand copper

conductors. The insulation grade for these wires shall be 660 volts. All control wiringshall preferably be enclosed in plastic channels or neatly bunched together.

For 16 AMPS control fuse circuit, 2.5 Sq.mm size COPPER wires shall be used.Each wire shall be terminated at a separate terminal. Termination of not more thantwo outgoing wires on a single terminal will not be acceptable. Wires shall not bejoined or tied between terminal parts. Shorting links shall be provided for all C.T.Terminals at metering / relay / instrument..

Each wire shall be identified at both ends by self-sticking wire marker tapes or PVCFerrules. Ferruling of wires shall be as per relevant IS / BS 108.

A minimum of 10% spare terminals shall be provided on each terminal block.Conductors shall be terminated with adequately sized compression type lugs."ELMEX" (direct conductor termination) type terminals will be acceptable for wires upto 10 sq.mm.

The control terminals shall be mounted in such a way that they are separate from thepower terminals and shall be easily accessible without any hindrance from the powercircuitry.

The cabling chamber of adequate size for accommodation, support and terminationof aluminium cables shall be provided at the rear.

Facility to extend cabling area by additional cable chamber shall be preferred.

The wiring shall be complete in all respects so as to ensure proper function ofcontrol, protection and interlocking schemes.

COMPONENTS:

I. AIR CIRCUIT BREAKER

ACB shall confirm to / IEC 60947 (Part I & III) / IS 13947 (Part I & III)

Suitable for a service voltage of 3 Phase, 660 V minimum, 50 Hz AC supply and shallhave an insulation voltage of 1000 V.

Possible to upgrade the degree of protection of ACB to IP:54. Minimum degree ofprotection of the ACB shall be IP:43.

Suitable for mechanism from front access.


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The microprocessor based Relay shall comply with IS 13947-1 for general rules andIS 13947-1 for standards pertaining to contactor shall be designed for AC3.

The microprocessor based Relay shall be suitable for Type 2 coordination as persuitable clause in the relevant Indian Standards.

The microprocessor based Relay shall be capable of offering differential protectionand shall be ambient compensated type, operable upto 70 .C.

The microprocessor based Relay shall be capable of withstanding short circuit equalto seventeen times the rated thermal current (17 Ie).

The microprocessor based Relay should have built in single phasing protection andphase unbalance protection as per IEC947-4.

The ACB shall be provided with 4 NO & 4 NC spare auxiliary contacts apart fromtheir inherent usage.

Interlock and Safety Arrangement

The ACB's shall be Three-position draw out type. Any attempt to with draw the AirCircuit Breaker, which the unit is in service, will automatically trip the breaker. It shallbe possible to rack the ACB main contacts in to disconnected position with the doorclosed.

Remote electrical indication of the circuit breaker status should be possible for all thepositions.

Possible to close the ACB electrically and the spring charging time shall bepreferably by less than 5 seconds. The mechanism shall be of stored energy type.The electrical closing mechanism shall have a built- in anti pumping feature minimum4 NO & 4 NC spare control contacts should be available for external use.

The ACBs are to be operated through a PLC programmer and should also providedwith electrical interlocking in between them incase of failure of PLC. And shall have aselector switch to select PLC / Electrical Interlock mode.

Rating and Breaking Capacity

The ACB shall have Minimum Service Breaking Capacity (Ics) equal to UltimateBreaking Capacity (Icu).

The Minimum Service Breaking Capacity (Ics) for rating 2500 AMPS shall be 65KA.

Protection


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TICEL BIO PARK- II ELECTRICAL ( HT & LT ) INSTALLATION WORKS

There shall be an option to select the curves (minimum 80 combinations) and alsochange the operating time for minimum of 8 settings for overload, 7 for short circuitand 7 settings for earth fault.

There shall be facility for selecting various type of E/F protection if required.

Trip history feature shall be available.

Neutral protection of 50 to 100% should be available.

Self - diagnostic malfunction alarm for microprocessor should be available.

"The trip unit shall have thermal memory.

I2 t cropping facility shall be available for short circuit and earth fault.

Facility should be there to monitor the load and intimate a pre-trip alarm or have load-shedding feature.

Fault indication by means of LED should be available for Overload, Short Circuit andEarth Fault and also LCD display for indication of menu's, settings, recordedinformation.

Trip reset facility should be manual / automatic.

II. MOULDED CASE CIRCUIT BREAKERS

MCCBs should comply with IEC 947 Part 2. / IS 13947

The MCCB shall be suitable for universal mounting (i.e) the Load / Line must beinterchangeable.

The MCCB shall be suitable for operating Voltage of 415 V minimum and anInsulation Voltage of 660 V.

MCCBs starting from 200 amps shall both variable ( O/L, SC ) and below shall bevariable over load / both fixed and fixed short circuit.

Rating and Breaking Capacity

The Service Breaking Capacity (Ics) in KA for MCCB shall be as mentioned in Bill ofquantities.


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Protection

Overload and short circuit setting details:-

All outgoing MCCBs in the Main Changeover panel and incoming MCCBs of all SubPanels shall be of adjustable overload and short circuit settings.

The outgoing MCCBs in the Sub Panels needs adjustable thermal overload settingsonly and fixed short circuit setting.

The Thermal setting shall be adjustable from 80% to 100% of its normal ratedcurrent.

The magnetic setting shall be continuously adjustable from 5 to 10 times of its setcurrent.

Trip reset should be available Manual / Automatic.

CONTACTORS

Contactors shall comply with IS 13947 1 for general rules and IS13947-4-1 forstandards pertaining to contactors and motor starters. The contactor shall be capableof withstanding breaking & making capacities per following:

AC3 Category

Making Current - 10 times Rated Current

Breaking current - 8 times Rated current

Contactor shall be capable of withstanding an impulse voltage of 8KV and have aninsulation voltage of 1000V.

The Contactors shall be capable of frequent switching and should operate withoutany deration at 55 . C for AC3 application.

The coil shall have 3 terminals and the insulation class shall be preferably H class,

to sustain frequent switching operations. The auxiliary contact block shall have aswitching capacity of 240V at 2A.

Contactors shall have one auxiliary in-built and it shall be possible to have additional2NO &2 NC contacts and they shall be easily interchangeable from NO to NC.

Contactors used for capacitor application shall have built in damping resistors &block of early make poles. For capacitors only capacitor duty contactors of respectiverating to be provided.


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Instrument Transformers:

Current Transformers shall be tape wound . The CT ratio and VA burden shall besuch that it can power all meters.

Current transformers shall generally conform to IS: 2705.

Current transformers for instruments shall have an accuracy class 0.5 for MV Paneland class 1.0 for sub panels and accuracy limit factor less than 5.0. The currenttransformers shall be capable of withstanding the peak momentary short circuitcurrent for 1.0 second. The neutral side of the current transformers shall normally beearthed through a link.

Wherever provided, the voltage transformers shall generally conform to IS : 3156and shall be cast resin type. The voltage transformers shall be provided with primaryfuses. Miniature circuit breakers with auxiliary contact shall be provided on thesecondary side.

The voltage transformers shall have an accuracy class 3.0 from 50% to 110% ofnormal voltage and class 1.0 from 80% to 120% of normal voltage.

Measuring Instruments:

All measuring instruments Digital / Analogue shall be of 144 x 144 mm (or) 96 x96 mm square flush mounting pattern.

All A.C Ammeter s, Voltmeters, KW meters shall be of Digital type except for the

Incoming meters or as per BOQ.

Control and selector switches shall be CAM operated rotary switches

The voltmeter selector switches shall be to measured voltage between phases with

OFF and 10A ratings.

The ammeter selector switches shall be 10A rating and to measure phase currentthrough CTs of 5A secondary.

Indicating Lamps:

Indicating lamps shall be provided in all the panels as required and they shall becentre to the visibility requirement as per I.S.


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TESTS:

The Panel design shall have undergone all the type tests as per IS: 8623. Type testcertificate shall be submitted along with the panels.

Routine test as per IS: 8623 on each completed switch boards shall be carried out inthe factory and witnessed by owner /Architect representative and approval obtainedbefore despatch and test certificates for the same shall be submitted.

Tests required as per IS on the completed panel boards as mentioned above andcommissioning are included in the tenderers scope.

INSPECTION:

The Inspection of the panel will be carried out by consultants representative atvarious stages of fabrications.

LABELLING

General

Every switchboard, switchboard control contactor, time switch, relay, indicator lamp,meter, motor starter, link and any control or protection equipment within or on aswitchboard shall be clearly and accurately labelled.

Labels shall be engraved laminated plastic or photo anodized rigid aluminum andshall comply with the following requirements.

Except where otherwise required labels shall be fixed adjacent to, but not on anyitem of equipment.

Engraved lettering shall be black on a white background, except that the label for amain switch shall have red lettering on a white background, and warning and cautionlabels shall have white lettering on a red background.

Fixing of Labels

Labels shall be securely fixed by :

Screws and adhesive, are fixed in an extruded aluminum section which shall becountersunk screw fixed or countersunk riveted to the panel. Screws shall betightened with nuts or into tapped holes in the switchboard. Mechanically expandedplastic rivets of minimum 6 mm. head diameter are acceptable instead of screws.Aluminum rivets may be used to fix aluminum labels only. Self tapping screws,thread cutting screws or other fixing are not acceptable.


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Labels on Exterior of Switchboards and Schedules

All switchboards shall be labeled with the manufactures name.

A switchboard designation label shall be provided. For other than main

switchboards, the designation label shall also state the source of electrical supply.Separate sections of enclosures shall be identified. The label for any section orenclosure containing supply Authority equipment shall be to the satisfaction of theConsultant / Employer and the Supply Authority.

Every switchboard control shall be labeled and shall include:

Circuit designation for all main switches, main controls and sub main controls.

Details of the Consumers mains and all sub mains

Incoming busbar & cable rating

The minimum height of lettering shall be as per the local Inspection regulatorystipulation.

Labels on Interior of Switchboards

Labels identifying equipment within a switchboard shall be located such that the itemreferred to is obvious and the lettering is not substantially obscured by the temporaryor permanent position of any equipment or wiring.

For plug- in equipment where items are physically but not functionallyinterchangeable, the label wording shall be expanded to clearly identify theremovable section (e.g to identify the contact configuration or timing range). Wherethis is not possible, a second identifying label shall be glue fixed to the removablesection.

The function and coding shown on the circuit diagram shall be used.

Earthing

Switchgear in the panel shall be provided with COPPER double earth connection ofsize indicated in the schedule and connected to the earth bus

Earth bus bar shall be supported at suitable intervals

All instruments and metering panel doors shall be connected to earth by using 2.5sq.mm. 650V, FRLS PVC multistranded copper conductor or flexible braided copperwire of equivalent size and directly connected to the earth bus of the panels


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The materials and size of the earth bus bar shall be as specified in the schdule

At either end of the earth bus provision shall be made for bolting the earth bus to theearth electrode with nuts & bolts and spring washer. The earth bus bar shall runalong the entire length of the board

Drawings and Data:

Vendors shall furnish following drawings for PMC / consultant approval before fabrication ofthe panel.

a) Tenderer shall also provide detailed GA diagram, sectional drawings

Terminal drawings and other drawings with all dimensions indicating compartmentscutouts, drill holes etc., for all the panel boards to the Consultant

b) Front and rear view of all switch boards indicating Switch Gear arrangements of

Various feeders/starters giving its location numbers and tag numbers for each as persingle line diagram.

c) Typical control schematic diagram for each type giving type designation to bereferred on Single line diagram

d) Switch board foundation/fixing details with all dimensions and details of shipping

sections.

e) All the catalogues, manuals pertaining to each and every ACB, MCCB, PLC, Meters,

CTs etc should be sent along with the panel boards.

f) Bill of Materials used in panels indicating the make of each items

g) Manufacturers and service providers address, contact person, contact no etc., has tobe sent to us for all the components.

GENERAL:

The gland plates shall be left undrilled and of 3mm thick

Inter panel partitions / barriers in sheet steel are required to be provided.

Busbar joint shrouds are required to be provided , so that it can be easily removedand refitted.

All internal wiring shall be done with crimping type lugs and all terminals are to beidentified / feruled properly.


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All vacant compartments above 100mm to be provided with earth strip.

Danger labels on rear doors shall be provided.

Necessary terminals has to be provided for BMS interface at all Panels.

Data sheet shall be referred for specification of the ACB & MCCB to be used inpanels.

No alterations drill holes welding etc., are to be done at site after the panel boardsare received from the factory.

The LT panel board shall comply with all rules & regulations as per CEIG norms andany modifications pointed out by them or any other statuary agencies during theirinspection also to be carried at free of cost before commissioning.

The LT Panels Degree of Protection : IP 52

COMMISSIONING:

The supplier shall render the service of his supervisor during the Installation andcommissioning of the panels at free of cost.


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1.0 GENERAL :

1.1 SCOPE ( D.G. SET ) :

This specification covers the design, construction features, manufacture and performance ofemergency diesel generator. The scope includes supply, installation, testing andcommissioning of D.G. set along with fuel pipe line, exhaust pipe insulation, pipe supportstructure, silencer, day tank, Synchronize panel etc in respect manner up to the satisfactionlevel of client.

1.2 CODES AND STANDARDS :

The design, manufacture and performance of the diesel generator and accessories shallcomply with all currently applicable statutes, regulations and safety codes in the localitywhere the diesel generator will be installed and with the latest applicable codes andstandards. Nothing in this specification shall be construed to relieve vendor of this

responsibility.

2.0 DESIGN & CONSTRUCTION :

2.1 GENERAL :

2.1.1 The diesel engine offered shall be of the regular production models of the manufacturer forindustrial applications and already type tested either at the manufacturers works or outside.The type test report shall be furnished to the purchaser for his review if so desired.

In case the proposed engine model has not been type tested, vendor shall furnish with theoffer, a reference list of its existing industrial installation and at least three of these engines,should have completed, 3800 hours of running at site.

2.1.2 Unless otherwise specified in the equipment data sheets, the diesel engine shall be providedwith class A1 governing as per the latest edition of B.S. 5514.

2.1.3 The Cyclic irregularity of the diesel engine for direct coupling to an electric generator,angular deviation of A.C. generators given by diesel engine for parallel operation, and theengine governor speed droop characteristics, shall be restricted to the values specifiedunder the latest edition of B.S. 5514.

2.1.4 The vendor shall be responsible for carrying out torsional analysis of the dynamic system asspecified in the latest edition of British Standard-5514. The results in the form of a report shallbe submitted to the purchaser for scrutiny and reference, if desired.

2.1.5 Vendor shall provide the flexible exhaust connections to connect the engine exhaust to theexhaust piping. The required size of the exhaust piping should be clearly specified by thevendor.

2.1.6 The common base plate for mounting the diesel engine and the driven equipment as well asthe flexible coupling, shall be supplied by the vendor.

2.1.7 Vendor shall indicate in the bid, the IS Noise Level rating of the diesel engine with the offeredexhaust silencer, which should not exceed more than 95 db at 3 Mtrs. distance.

TECHNICAL SPECIFICATIONS FOR DIESEL GENERATOR SET


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2.2 ENGINE STARTING :

2.2.1 Diesel engines shall be capable of starting without the use of cold starting aids so long theambient temperature at the site is not below 4 c.

2.2.2 Where the diesel engine is specified / offered with battery starting arrangement, the startermotor shall be capable of starting the engine without having to disengage the driven machinewith the help of a clutch. Where the diesel engine is equipped with a dual starter thesynchronizing switch and the corresponding wiring / connection with the starter motor shallbe provided by the vendor.

In case of diesel engines driving the engine mounted battery charging alternator, the Vendorshall also provide automatic battery charging equipment suitable for taking power from supplyauthoritys power source and mounted on a free standing type of a panel.

The battery charger as specified in the equipment data sheet, shall be capable of delivering acurrent equal to 100% of the 20 hour discharge rate of the battery and also equipped withcharging rate selector device.

2.2.3 As specified in the data sheets, the diesel engine is required to start / stop automatically, thevendor shall provide the necessary controls ( automatic - cum -manual ) in the engine paneland the interconnecting wiring and piping from the panel to the engine and startingequipment. A pilot lamp shall be provided in the line side of the starting equipment circuit toindicate that the controller is in the automatic position. In the event the engine does not startafter three attempts have been made, the controller shall stop all further cranking andoperate the audio-visual alarm. A D.C. motor driven lubrication pump with timer suitablyinterlocked with the starting system shall be provided by the vendor. Whenever the unit isarranged for automatic shut down, a running period time set for a specific time interval, shallbe provided.

2.3 ENGINE COOLING :

2.3.1 Vendor shall supply complete cooling system. If it is water cooled, the vendor shall submitwater softening plant for the same.

2.4 ENGINE FUEL SYSTEM :

Engine fuel system shall be complete in all respects but not limited to following :

2.4.1 The daily service fuel tank shall be equipped with shielded level gauge, strainer and a handhole of not less than 150mm diameter, besides the required fuel connections and a drainplug. One tanks of 990 ltrs. Capacity to be provided.

2.4.2 The inside surfaces of the fuel tank and the float tank shall be coated with Enamel Red or Blackof I.C.I. or its equivalent and the outside surface to be given two coats of the oil resistant primer

paint. The fuel tank shall be hydrostatically tested at a pressure not less than 0.35 Kg./Cm.

2.4.3 Electrically operated fuel oil transfer pump to transfer oil from barrels to day tank shall also beprovided.

2.4.4 All piping, valves, fittings and supports inside D.G. house shall be part of supply.


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2.5 ENGINE EXHAUST SYSTEM :

The exhaust system should be designed based on exhaust gas analysis and as perprevailing CPCB norms. Necessary steel structure should be designed and erected forrequired height of stack. Guaranteed emission levels should be submitted toclient/consultants.

3.0 INSPECTION & TESTING :

3.1 The inspector-representing Purchaser shall have entry to the plant while and wherever workfor the equipment is being performed.

3.2 The vendor shall have the responsibility of providing purchasers representative with allrequisite facilities / equipment for carrying out satisfactory testing.

3.3 The diesel engines shall be tested in the presence of purchasers representative accordancewith latest edition of B.S. 5514 or any other equipment standard as agreed to with thepurchaser before the finalization of order.

3.4 The routine load and fuel consumption test shall be of the 4 hours. It should be carried out at100%, 50% & 25% loads as per mutually agreed time (at extra cost).

3.5 Unless otherwise specified, 10% overload provision shall be kept while setting the fuel stopfor the site running.

3.6 The engine control panel/s after assembly and wiring, shall be functionally tested in thepresence of the clients / consultants representative.

4.0 ALTERNATOR :

4.1 This specification define the requirements of design, manufacture, testing and supply of selfexcited emergency generator complete with automatic voltage regulator, control panel,generator breaker and other accessories as specified in the material requisition.

4.2 Unless otherwise specified the emergency generator shall be supplied complete with :

a ) Brush less excitation system complete with AVR.

b ) Electric panel including control cubicle and associated auxiliary devices, relay panel andgenerator breaker battery and charger.

c ) Air inlet and outlet for generator cooling (inlet shall be oriented to suit local plant layout ).

d ) Lifting arrangement for the machine.

e ) Foundation frame complete with foundation bolts and base frame.

f ) Lube oil system integral with the prime mover lube oil system.

g ) Spares for commissioning.

h ) Spares for two years of operation and maintenance. (Quote separately)

i ) Any other part / accessories not specifically mentioned above but considered necessaryfor safe and reliable operation.


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5.0 CODES AND STANDARDS :

Unless they are in variance with the clause of this specification the diesel engine drivengenerator and their components shall comply with the latest edition of the applicablestandards listed below :

IS : 2253 Designation for type of construction and mounting arrangement of rotatingelectrical machines.

IS : 4691 Degree of protection providing by enclosures of rotating electricalmachinery.

IS : 4728 Terminal marking of rotating electrical machines.

IS : 7132 Guide for testing 3 Ph. Sysn. Machines.

IS : 5422 Turbine type generators.

IS : 4889 Methods of determination of efficiency of rotating electrical machines.

IS : 1271 Insulating materials for Electric machinery and apparatus in relation totheir thermal stability service, classification.

IS : 4722 Specification for rotating electrical machines.

IS : 2516 A.C. circuit breakers.

6.0 DESIGN AND CONSTRUCTION :

6.1 The alternator design shall meet the requirement specified in data sheet and shall be suitablefor the site conditions specified therein.

6.2 The alternator shall be mounted on a common base frame together with the prime moverunless otherwise agreed. The generator shall be provided with necessary lifting hooks andtwo earth terminals for connection to main earth grid.

6.3 The alternator winding shall be class H/F insulation with temperature limitation.

6.4 The stators windings shall be brought out to six insulated terminals in two separate terminalboxes. The alternator shall therefore, be provided with three separate terminal boxes. Thealternator shall, therefore, be provided with three separate terminal boxes i.e. for the line andneutral stator connection and for control connection. The terminal box for the line terminalshall have sufficient space for the termination of cable size specified in data sheet. Theneutral box shall in addition to the space for neutral earthing cable shall have sufficient roomfor the current transformers used for the protection of the generator. Star connection shall beformed in the neutral side of terminal box. The terminal box for control cable shall containproperly marked terminals for all internal equipments e.g. embedded temp. detectors etc. Allterminals shall be stud type. The terminal boxes shall be complete with lugs and doublecompression type cable glands. Current transformers shall be as specified in data sheet.

6.5 All parts and accessories shall be suitable to withstand stresses due to over speed / overload/ short circuit conditions specified.


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6.6 Bearings shall be double shielded and prelubricated. Grease in the bearing enclosure shallprovide additional lubrication to bearings as wel as provide sealing against dust andmoisture.

6.7 The alternator shall be air cooled unless otherwise agreed, alternator enclosure shall be asspecified in data sheet.

6.8 The direction of rotation of the rotor of the machine shall be compatible with that of the primemover. A clear indication of the direction of rotation shall be given on either end of themachine.

6.9 Space heaters shall be installed within the enclosure, location and max. surface temperatureof the heaters shall be such that no damage can be caused to any insulation. Heaters shallsuitable for operation on a single phase 240v AC supply unless otherwise specified.

A suitable double pole switch shall be mounted on or adjacent to the stators frame orenclosure for the manual switching off of the heaters.

6.10 Field winding shall have class F insulation with excellent electrical and mechanicalproperties. The field winding shall be capable of operating at a field voltage of 125% of ratedload field voltage for at least one minute starting from stabilised temperatures at a ratedconditions.

6.11 A rating plate of corrosion resistant material shall be fixed on the generator frame and shallgive the following information :

a ) Manufacturers name.

b ) Serial Number, Type and frame reference

c ) Rated output in KVA & KW

d ) Rated power factor, frequency and voltage

e ) Rated stators current and speed in Rev. / Min.

f ) Class of insulation

g ) Phase rotation ( CW or CCW )

h ) Customers indent no.

i ) Year of manufacture

j ) Weight rotor and stators in Kg.

7.0 EXCITATION SYSTEM :

The generator shall be provided with brush less type solid state excitation system withautomatic voltage regulator. The excitation system shall include the automatic voltage

regulator, AC exciter and rotary rectifier. The field of the exciter shall be fed from the statorswinding through a suitable transformer and AVR. AC voltage generated in the AC excitershall be rectified by the rotary rectifier assembly and fed to the main field circuits. The rotorwindings of the AC exciter, the rectifier assemble, main field winding of the generator andother accessories on rotor part shall be rigidly fastened to the shaft and the connection withdifferent items shall be anti-loosening type.

The exciter capacity shall be at least 20% more than the maximum requirement at any time.The exciter winding shall be insulated with class F insulation.


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Automatic solid state voltage shall be provided with the following features as a minimum.

- Under frequency protection.

- Short circuit protection.

- Manual voltage control switch with adjuster.

- Cross current compensation for parallel operation.

- Voltages build up circuitry.

- Stators current limiter.

- Field current l imiter.

The current and potential transformers required to feed the AVR from the generator terminalshall be adequately rated.

8.0 SYSTEM OPERATION :

The emergency generator set shall normally be in an unattended area. The control systemshall operate in fail-safe mode and shall include all controls and protection necessary for the

safe operation of the package. The generator set shall function as per one of the followingschemes :

- Manual start in service mode.

- Manual test mode.

9.0 GENERATOR CONTROL PANEL :

9.1 The local generator control panel for the generator set shall comprise of the following unlessotherwise specified in the attached data sheet.

a ) Automatic voltage regulator.

b ) Metering equipments.

c ) Indicating instruments.

d ) Local Air circuit breaker for DG set.

Any other accessory require to make the generator set operational as a package shall beincluded in scope of supply. If required the generator control panel shall be split into variousfunctional sections vi. protection, metering and control, regulation etc.

The generator breaker shall also be part of the control panel unless otherwise specified. Thebreaker rating shall be as specified in the drawing. The protective relays in the Gen. Controlpanel shall act to trip this breaker on fault conditions unless otherwise specified. This breakeralso serves the purpose of local isolation.

All motor starters for generator set auxiliaries shall be DOL type.

9.2 The panel shall be free standing, metal enclosed, dust and vermin proof type with a hingeddoor and having a degree of protection IP 51 as per IS : 2147 unless otherwise specified.Power and control equipment shall be segregated inside the panel as far as practicable. Themaximum height of the operation handle/ switches shall not exceed 1000 mm. and theminimum height not below 300 mm. All hardware shall be corrosion resistant and bolts, nutsand washers shall be made of galvanised zinc passivated of cadmium plated high quality


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TECHNICAL SPECIFICATIONS FOR DG CONTROL PANEL SUITABLE TO SYNCHRONIZE

LOAD SHARING FACILITY

The Control Panel shall have AMF cum Auto Synchronizing of DG Sets with Auto Load Sharing facility

for Diesel Generating Sets .

The Panel/s shall be totally enclosed dust tight & vermin-proof, floor mounted, compartmentalized type,fabricated from processed 14 / 16 gauge CRCA Sheet Metal. The Panel shall have gland plate atbottom/top for input and out going cable terminations.

The panel shall be fitted with following instruments and pre-wired with coded flexiblecopper cable withferrule numbers for easy identification & maintenance.

The DG Control Panel suitable forAMF, Auto Synchronizing & Auto load sharing facilityshall be scientifically designed, manufactured and supplied as mentioned below.

The Control Panel shall be supplied with Imported Microprocessor based, D.G. Set -

Controller programmed for complete Controls of Engine & A.C. Generator and completeMonitoring & Protection of Engine & A.C. Generator.

The controller shall also have AMF/Manual/Test/Load dependent Start/Stop, Auto/ManualSynchronizing, Auto active & reactive Load Sharing and Soft load transfer capability with AMFfacility.

AMF CONTROL:

The controller can sense loss of mains i.e. if the mains voltage & frequency is unhealthy(beyond the set limit) & initiates the Engine Start Cycles after monitoring adjustable blackoutdelay time. In case of the DG Set not being started, it again attempts to start the DG Set tillthree attempts. On successful starting of the DG Set it monitors the Generator power supply andtransfers the load to DG Set ensuring the interlocking. In case of DG Set fails to start, it locksout further starting attempt and initiates the starting failure alarm.

When power supply resumes back, the Unit monitors the healthiness of the same for adjustabletime and then-after it transfers load back to the mains and stops the DG Set after cooling downtime and remains ready as Stand-by.

LOAD DEPENDENT AUTOMATIC START/STOP CONTROL:

For Multiple DG Sets, the controller can be programmed for automatically starts of additional DGSet/s when load exceeds set percentage of rated load of operating DG Set/s. It also control to

unload the DG Set/s when the load falls below the set limit and stops the DG Set after adjustedcooling down time and remains ready as Stand-by.

Control Monitoring Protection & Synchronizing:

The Panel shall be fitted with Imported Microprocessor based, State-of-art technology D.G.Set -Digital Control Package duly programmed for complete Digital Controls comprising of Control,Monitoring & Protection of Engine & A.C.Generator, Manual & Load Dependent Auto Start/Stop, Auto

/ AMF 2x250 KVA DG SETS WITH AUTO STARTING, AUTO SYNCHRONIZING & AUTO


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Synchronizing, Auto active & reactive Load Sharing and Soft load transfer capability. The unit shall alsohave AMF facility and can be expanded for Grid Synchronizing. The specification & facility are asmentioned below:

Specification:- Voltage Input 3-phase, Star or Delta wire, Range 50-60Hz, 110-480V V AC- Current Input 3-Phase, 5Amp.at Max. Load. Burden 1.25VA per phase at 5A.- Load sharing within +/- 5%- Auxiliary Voltage - DC 16-32V- Operating Temperature: Minus 40 to 70Deg.C.- Key Pad Operator Interface- Compatible for PC Interface- Confirms to EN 55011: 1991,IEC 1000

Operator Interface & Display

The unit shall have- Key-Pad for scrolling display data, configuration & control with Key for Up-Down, Enter, Escape

etc.

- LCD window display for monitoring various parameters as detailed bellow

Control, Monitoring & Protection For Each Engine:Control:- Engine Pre-Glow (Pre-heating)- Fuel Solenoid Control- Engine Starter Control- KVA Controlled Cool-down Timer- Engine Auto Start/Stop (AMF)

Monitoring (Digital):- Battery Voltage Monitoring- Speed Monitoring

- Engine hours

Protection (Digital):- Low Lub Oil Pressure- High Water Temperature- Battery Voltage (Over/Under)- Over Speed- Under speed

Control, Monitoring & Protection For Each Generator (Alternator):

Control:

- ACB monitoring

- Dead Bus Monitoring- ACB Closing- ACB Tripping

Load maganger Monitoring (Digital):- Voltage- Ampere- Frequency- KW on R, Y, B, and Total on three phase.


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- KWh- KVA R, Y, B, and Total on three phase.- PF- KVAr

Protection (Digital):- Under Voltage (27) Trip, with adjustable range of rated Voltage & with adjustable Timer to Trip

the generator for persistent under voltage.- Over Voltage (59) Trip, with adjustable range of rated Voltage & with adjustable Timer to Trip the

generator for persistent over voltage.- Under Frequency (81U) Trip, with adjustable range & with adjustable Timer to Trip the generator

for persistent under frequency.- Over frequency (81O) Trip, with adjustable range & with adjustable Timer to Trip the generator

for persistent over frequency.- Reverse Power (32) Trip, with adjustable range & with IDMT characteristic to trip the generator

for persistent Reverse Power.- 3 Pole Over Current (51) Trip, with adjustable range & with IDMT characteristic to trip the

generator for Over Current.- Loss of Excitation (40)

- Synchronizing Check Relay- CDV62 or equivalent relay- Differential protection relay- Restricted Earth Fault relay- Above relay should be descriptive relaySynchronizing:

Auto Synchronizing (Digital):

- Auto sequencing- Digital single processing- Phase, Frequency and Voltage Match- Built-in sync check relay

- Adjustable Frequency Matching Window- Adjustable Phase Angle Window- Adjustable Voltage Matching Window- Adjustable Stability and Phase Gain- Voltage Match Relay Output Control- Internal dead bus and relay sensing control- Manual voltage adjustment for manual synchronizing- Manual speed adjustment for manual synchronizing- Display of synchronizing while parameters i.e. phase angle, Voltage difference, and Frequency

difference.

Manual Synchronizing:

- The Microprocessor unit shall have in built Manual digital Synchronoscope

Load Sharing & Load Control (Digital):- Real (KW) Load Control- Isochronous Load- Sharing- Reactive (KVAr) Load Control- Isochronous Load- Sharing- Adjustable Droop for Manual Synchronizing


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- Adjustable Load Pulses Sensitive- Load Ramping- Adjustable Low and High Power Limit- Load depended Start/Stop with Auto Synchronizing.

Mains Control:- The unit/s shall also have facility to monitor the mains (Grid) power for auto start/ Stop

facility (AMF) to start the D.G.Set on failure of Mains power. The unit shall have followingmonitoring & Protection of Mains

Electrical (Mains):

- Under Voltage (27) with adjustable range of rated Voltage & with adjustable Timer to monitorMains supply & trip Mains breaker for persistent under voltage.

- Over Voltage (59) with adjustable range of rated Voltage & with adjustable Timer to monitorMains supply & trip Mains breaker for persistent over voltage.

- Under Frequency (81U) with adjustable range of rated Frequency & with adjustable Timer tomonitor Mains supply & trip Mains breaker for persistent under Frequency.

- Over frequency (81C) with adjustable range of rated Frequency & with adjustable Timer to

monitor Mains supply & trip Mains breaker for persistent Over Frequency.

Annunciations / Indications:

- The fault annunciation for each Engine & Electrical fault shall be displayed in the LCD window ofmicroprocessor unit with event recording facility.

Power Circuit / Breaker:

- Electrically operated Air Circuit Breaker with Under Voltage / Shunt Release, 240V AC Motor,Closing Coil

- Set of PVC sleeved copper Busbar

- set of CTs (5P10) for metering cum protection

24V DC Battery Charger(common) :Comprising of:- DC Ammeter (Analog type - 72 sq. mm.)- DC Voltmeter (Analog type - 72sq.mm.)- Selector Switch of Trickle / Boost / Off- Transformer / Rectifier - Trickle/ Boost/Off Selector switch

Set Of Push Buttons and Selector Switch:

- Set of Push Buttons for each DG Set:- Emergency trip (Mushroom - lockable type)- D.G. ACB Close- D.G. ACB Trip- Engine Start/Stop- Set of Selector Switches for each DG Set:- Auto / Test / Manual/Off Selector Switch- D.G. Selector Switch- Voltage Raise


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- Voltage Lower

Miscellaneous:- Set of Control Fuses- Set of control relay/ aux. connectors.- Indicating & Rating Name Plates- Mounting Base Channel

- Set of Control Cable connectors- 1No. Audio Alarm Hooter - Name Plates

A.M.F Cum Auto Synchronization CONTROL PANEL

SCOPE OF SUPPLY

AUTO- SYNCHRONIZING PANEL

Operation of Panel:

1.Manual Mode :The DGs can be started & Breakers can be closed from the Panel itself.

2.AMF i) Start :In AMF mode , as soon as a command will Come from Mains failurepanel both the DG Sets will Start automatically, synchronize automatically& load Sharing will be done automatically.

ii) Stop: As the command will be removed from the Main Failure panel both theCircuit Breakers of DG incomer Will open & the DGs will stop afterprogrammable cool Down cycle.

Note : In case of any trouble in relay, each DG set should be able to run on Individual modewith & without Synchronous Panel.

This panel shall be suitable for Auto-Synchronizing Panel of 2 X250 KVA DG Sets


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TECHNICAL DATA SHEET FOR DIESEL GENERATOR SET

Sr. No. Particulars Description

1.0 Prime mover Diesel Engine

2.0 Quantity required 2 No.

3.0 Service Standby source at outdoor location

5.0 RPM 1380

6.0 Voltage 415 V TPN, 3%

7.0 Voltage variation / regulation

Steady state - slow variation

In load (0.0% to 100% at P.F. 0.8)

1% or less

8.0 Voltage deep (sudden loadapplication 0.0% to 100% at P.F.0.8)

-5%, recovery time - 0.25 sec.

9.0 Frequency 50 Hz.

10.0 Frequency variation / regulation 0.5 Hz.

11.0 Temperature rise Class 'F' used as Class 'B'

12.0 Alternator Insulation Material VPI Insulation preferred

13.0 Flywheel Required

14.0 Vibration damper Required ( fluid type only )

15.0 Fuel pump air cleaner Required

16.0 Fuel pump Required

17.0 Oil filter, fuel filter etc. Required

18.0 Lub oil pump Required

19.0 24 V DC electrical systemconsisting of SMF lead acidbattery set and suitable charger

Required

20.0 Safety controls Required

21.0 Residential type Silencer Required

22.0 Acoustic Hood Required

23.0 AMF/Sync. panel with breaker Required

24.0 Coupling Required

25.0 Instrument panel consist of

a ) Starter switch with key

b ) Lub oil temp. gauge

Required

Required

Required

4.0 Rating 250KVA


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c ) Water temp. gauge

d ) Lub oil pressure gauge

e ) Tacho cum Hour meter

Required

Required

Required

26.0 Fuel tank Required

27.0 Battery charger Required ( Electronics float & boosttype )

28.0 Engine testing

a ) At shop

b ) At site

Required

Not Required

29.0 Tool kits Required

30.0 Literature (Two sets each)

a ) Operation & maintenancemanual

b ) Parts catalogue / list

Required

Required

31.0 Cable Box & KWH meter Box Bypass cables required as per SLD, box should be suitable sizedfor same

Note :

1. The engine H.P. should be selected so as to achieve required KW rating to be generated at sitecondition considering no deration.

2. D.G. set should be able to start by push button starting or AMF panel.

3. The engine test shall be witnessed by the clients representative.

4. The engine should have automatic belt tensioning arrangement for battery charging alternatorsystem.

5. The engine should be fitted with sump oil drain pump fitted on the engine itself.

6. Engine should preferably be only four stroke and with air to air after cooler.

7. Engine should be preferably from the engine manufacturers who maintains quality - assuranceto international standard of ISO 9001.

8. Engine should be fitted with electronic governor only.


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9. DATA SHEET TO BE FURNISHED BY THE BIDDER FOR DIESEL GENERATOR SET


1.0 DIESEL ENGINE & AUXILIARIES

(DESIGN FEATURES)

1.1 Name of manufacturer

1.2 Rating standard BHP

1.3 Engine rating at site

1.4 Maximum engine rating at site

1.5 Derating factors

a) Altitude

b) Inlet air temperature

c) Humidity

d) Others

1.6 Period of maximum engine rating

1.7 Operating speed

1.8 No. of strokes per cycle

1.9 No. of cylinders

1.10 Arrangement of cylinders

1.11 Rotation direction (Viewed fromalternator end)

1.12 Compression ratio

1.13 Super charging air pressure atrated speed

1.14 Firing order (Viewed from powertake-off end)

1.17 Fuel system injector pressure

1.18 Fuel system booster pumppressure

1.19 Lub. oil temperature at pump inengine sump

1.20 Lub. oil pressure at pumpdischarge

1.21 Minimum level of lub. oil

1.22 Fuel oil system

1.22.1 Type

1.22.2 Filters :


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a) Type

b) Number

c) Location

1.22.3 Day tank :

a) Capacity

b) Material

c) Location

1.22.4 Grade of fuel oil to be used

1.23 Lub. oil system

1.23.1 Type

1.23.2 Filters :

a) Type

b) Number

c) Location

1.23.3 Lub. oil tank (sump) :

a) Capacity

b) Material

c) Location

1.23.4 Grade of lub. oil to be used

1.23.5 Lub. oil pump :a) Type

b) Capacity

1.23.6 Lub. oil cooler :

a) Type & heat transfer area

b) Oil inlet and outlet temperature

1.23.7 Lub. Oil change period

1.24 Jacket water system :

1.24.1 Type

1.24.2 Quality of water to be used

1.24.3 Quantity of water (Mtr.cu./hr.)

a) Engine cooling circuit

b) Lub. oil cooler

c) Turbo charged cooler


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1.24.4 Make up tank :

a) Capacity

b) Material

c) Location

1.25 Air intake system :

a) Intake filter type

b) Location

1.25.1 Total air quantity required :

a) For engine

b) For cooler

c) For charging

1.26 Exhaust gas system :

1.26.1 Manifolds :

a) Location

b) Size

c) Construction

d) Material

1.26.2 Exhaust silencer :

a) Type

b) Locationc) Quality of exhaust gas

1.27 Minimum loading of D.G. sets uptowhich it can be operatedeconomically

1.28 Period between major overhauling

1.29 Starting time of D.G. sets

1.30 List of all auxiliaries with ratings

1.31 List of spare parts for 2 yearsmaintenance period

2.0 GENERATOR ANDACCESSORIES :

2.1 Name of the manufacturer

2.2 Design rating

2.3 Continuous output rating at siteconditions


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2.4 Maximum rating

2.5 Power factor

2.6 Rated voltage and time taken to

reach full voltage

2.7 Method of Excitation andregulation

2.8 Rated current per phase

2.9 Speed

2.10 Frequency

2.11 Insulation class :

a) Stator

b) Rotor

c) Exciter

2.12 Temperature rise above ambient(by thermometer)

a) Stator

b) Rotor

c) Core

2.13 Generator parameters :

a) Synchronous reactance

b) Transient reactancec) Sub-transient reactance

d) Zero sequence reactance

e) Negative sequence reactance

f) Resistance of field winding atoperating temperature

g) Resistance of stator winding atoperating temperature

h) Maximum circuit current

i) Duration for which D.G. set canwithstand above

2.14 Cable Box

3.0 PERFORMANCE GUARANTEE :

3.1 Net electrical output at site afterengine derating factors andauxiliary power requirements havebeen taken into account


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3.2 Fuel oil consumption (actual) :

a) load

b) load

c) Full load

3.3 Lub. oil consumption at rated load(actual) per engine hour operation

3.4 Jacket water temperature IN toengine.

3.5 Jacket water temperature OUTfrom engine.

3.6 Lub. oil temperature IN to engine.

3.7 Lub. oil temperature OUT from

engine.3.8 Vibration and noise at rated

output.

3.9 Generator efficiency :

a) load

b) load

c) Full load

3.10 AMF compatibility

3.11 Generation cost per unit including

fuel oil cost, lub oil cost,maintenance & spares costsupporting with calculation

3.12 Engine life in hours

4.0 WEIGHT SCHEDULE :

4.1 Weight of engine with fly wheelincluding standard accessories

4.2 Weight of generator with exciter

4.3 Weight of common base frame

4.4 Heaviest single piece to be

handled during erection andmaintenance and its weight

5.0 DIMENSIONS :

5.1 After engine and generator areassembled

5.2 Maximum dimensions of the singleitem to be transported


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6.0 OTHER DATA :

6.1 Foundation requirements

6.2 Any other special requirement at

site for operation / installation?

6.3 Clearances required at site

6.4 Air changes required for DG room

7.0 DRAWINGS (WITH OFFER) :

7.1 General arrangement showinginternal layout and exhaust system

7.2 Generator control panel GA

8.0 DOCUMENTS (WITH OFFER) :

8.1 Relay catalogues indicating all

features and settings


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SCOPE

Supply, erection, testing and commissioning of standard make distribution boardsconforming to relevant Indian standards (IS 8623) and specifications given below.

GENERAL

Distribution Boards Shall Consist Of Following.

MCBs and ELCBs of reputed make and designed capacity, which shall conformto IS 8878 latest.

Neutral strip/earth strip for connecting all distribution point neutral/earth wires ofguest room.

Two numbers brass bolts and nuts on DB base for its earthing.

Cable conduit entry boxes on top and bottom as per design drawing.

However the specifications herein after described shall take precedence over theabove wherever this specifications call for a higher standard of material or workmanship.The distribution boxes shall be of standard factory make and flexibility shall be given tomount MCBs and ELCBs of any make.

CABINET DESIGN

Distribution boards shall be of totally enclosed type with dust and vermin proofconstruction. The enclosure shall be made of steel sheet of 18G. The steel sheet shallbe treated with a rigorous rust inhibition process before fabrication. The distributionboards shall consist of Earth Leakage/Miniature Circuit Breaker as in-comer and required

number of miniature Circuit Breakers as outgoing. The distribution boards shall be withtop and bottom cable/conduit entry. The incoming and outgoing shall be rated asspecified on the drawings and schedule; and both shall be totally isolated from oneanother. The cabinet shall be spray enameled to required colour shade finish. Theinterior components of the DB shall be mounted on Din Rails, mounted on the studsprovided inside the cabinet. A cover made of hylam sheet, or spray enameled 16G steelsheet, shall be provided over the cabinet, with slots for operating knobs or breakers.

The cabinet shall be equipped with 16/18G inside hinged front door having a spring latchand lock over flanged door. Cabinets shall have detachable gland plates at both top andbottom made out of 16/18G. The hinged type door shall be with U shape edge toprovide square type compressed rubber gasket.

The construction of the hinges shall be to enable the door to swing open by not less than150. In addition to this, the hinged design shall permit doors being completely removedwhenever necessary.

11. GENERAL REQUIRMENT OF MCB DISTRIBUTION BOARDS


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MINIATURE CIRCUIT BREAKERS (MCB)

Miniature Circuit Breakers shall be quick Make and Break type, and shall conform to relevantIndian Standards. The housing shall be heat resistant and shall have high impact strength.MCBs shall be flush mounted and shall be provided with trip free manual operating lever andON and OFF indications. The contacts shall be provided with magnetic and thermalreleases for short circuit and over current. The device shall have a common trip bar in thecase of DP and TPN Miniature Circuit Breakers.

MCB for ratings upto 125 Amps shall be available in 1,2,3 or 4 pole versions. MCB casingshall be made of self-extinguishing material tropicalised treatment 2 (relative humidity) 95%at 55C).

MCB shall comply with IS 8828-1996/IEC 898 1995.

It shall be suitable for use in frequency range 40Hz to 60Hz and shall accommodate AC/DCsupply according to requirements.

Arc chutes should be provided for effective quenching of arc during operations and faultconditions.

It shall have trip free mechanism and toggle shall given positive contact indication.

It shall have trip free mechanism ad toggle shall given positive contact indication.

It shall be suitable for mounting on 35mm DIN rail/surface mounting.

Line supply may be connected to either top or bottom terminals i.e. there shall be no lineload restriction.

Degree of protection, when the MCB is flush mounted, shall be IP40.MCB & shall besupplied with clamping terminals fully open.

Contact closing shall be independent of the speed of the operator.

MCBs operating temperature range shall be 20 deg C to + 60 deg C.

The characteristics should be in accordance with IS 8828 1996. The breaking capacity ofthe MCB shall be 10kA and energy limiting class3.

The rated impulse voltage of the MCB shall be greater than 4kV.

The MCB shall be capable of being used as Incomer circuit breaker and shall be suitable foruse as an isolator.

Contact closing shall be independent of the speed of the operator.

Electrical endurance of the MCB shall be greater than 4kV.

Power loss per pole shall be in accordance with IS 8828-1996 and the manufacturer shallfurnish the same.In case of multipole MCBs in a single location (DB), it shall be possible to remove MCBwithout having to disturb other MCBs in the vicinity.

C curve type MCB should be used for lighting & power loads.


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RESIDUAL CURRENT CIRCUIT BREAKER (RCCB)

RCCB shall comply with IS 12640-1988 /IEC1008. It shall be available in 2 pole and 4 poleversions and threshold sensitivities (non-user adjustable) of 30m A, 100m A 300mA &300mA with inbuilt time delay of 200mS for discrimination with downstream ELCB, ifspecified in schedule of quantities. Tropicalisation: treatment 2 (relative humidity 95% at55C).

The current rating shall be from 25A to 125A. Ratings ad sensitivities shall be as specified inschedule of quantities.

It shall be operationally independent of line voltage.

There shall be clear identification of earth fault or overload/short circuit fault on the RCCB.

The RCCB shall not given nuisance tripping due to transient over voltages (lightening, linedisturbances or other equipment).

The RCCB should preferably be Si class type (should be suitable for SMPS loads i.e.unaffected by the D.C pulsated components present if any in the circuit), and should not givenuisance ripping. Details to be furnished confirming suitability.

The short circuit withstands capacity of the RCCB without the associated shortcircuit/overload protection should preferably be 6kA.

A test device should be incorporated to check the integrity of the system and trippingmechanism.

Terminals should ensure easy termination of cables and should provide covers to shieldincoming and outgoing terminals with IP20 degree of protection.

The RCCB should be suitable for DIN rail mounting.

INDICATING LAMPS

Type : Panel mounting Protected LED types.(I.e. protection is provided againstElectromagnetic interference & overVoltage)Standard applicable : IEC 947-5-1Electric shock protection : class 2(IEC 536)Degree of protection : IP 65 9(IEC 529)Diameter : 22mm

Voltage : 230V AC

.


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PUSH BUTTONS

Type : Manually operatedSpring return type.

Standard applicable : IEC 947-5-1

Electric shock Protection : class 2 (IEC 536)

Degree of protection : IP65 (IEC 529) Rated Insulation Voltage : 600V

Rated Impulse voltage : 6Kv

Diameter : 22mm

Type of mounting : snap type

Color of actuator : Start PB GreenStop PB Red

Test PB BlackReset PB Yellow

Contact configuration : I NO or I NC

Contact rating : AC -15, 3A, 240V

TERMINALS

Distribution Boards shall be provided with a terminal block for neutral and earthterminations of adequate size. The terminal block shall be so located as to preventcrowding of wires in the proximity of live parts.

DIRECTORY

Distribution Boards shall be provided with a directory indicating the areas of loadsserved by each Circuit Breaker, the rating of breakers, size of conductors, etc. Thedirectory shall be mounted in metal holder with a clear plastic sheet on inside surfaceof the front door. A suitable size Danger plate indicating voltage grade shall also befixed inside the DB front cover.

INSTALLATION

Distribution Boards shall be wall surface mounted or recess mounted as required andat the locations shown on the drawings. The Boards shall be fixed on 30 x 40 x 6mmangle iron framework and bolts for surface installation. All the cables/conduits shallbe properly terminated using glands/grips/check nuts, etc. Wiring shall be terminatedproperly, using crimping lugs/sockets and PVC identification ferrules. No bareconductor shall be provided inside the board.

Distribution boards shall be bonded to the earthing system at least at two pointsusing brass bolts and lugs.


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Scope:

Supply, installation, storing, laying, fixing, jointing, terminating, testing and

commissioning of Medium Voltage PVC sheathed Armoured Aluminium ConductorCables XLPE insulated, cores laid-up with Polypropylene central filler and tape, extrudedPVC inner sheathed, GI wire/strip armored and PVC outer sheathed overall confirming toIS 1554 part I 1988 with latest amendments and specifications given below, laid in builtup trenches, directly buried underground, on cable trays, in pipes, clamped directly towall or Structures.

Type

Medium voltage cables shall be aluminium conductor, XLPE insulated, PVC sheathedand steel wire flat armoured or steel tape armoured construction. The cable shall havestranded, sector shaped aluminium conductors for cables of 4 Sq.mm size and above.

The cables shall be rated for a voltage of 650/1100 Volts.

Core Identifications shall be provided with the following colour scheme of XLPEinsulation

Single Core: Red/Black/Yellow/Blue Two Core: Red and Black Three Core: Red, Yellow and Blue 3 or 4 Core: Red, Yellow, Blue and Black

Conductor

Conductors are made from electrolytic grade aluminium/copper conforming to IS:8130,are compact circular or compact shaped, solid/stranded circular.

No of strands to be provided for circular compacted or shaped conductor to achieve

better-compacted conductor.

Sl.no Size in Sqmm copper Aluminium

1 1.5 3 ----

2 2.5 3 ----

3 4 7 3

4 6 7 3

5 10 7 7

6 16 7 7

9. GENERAL REQUIRMENT OF M.V. CABLES - (XLPE)


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Sl.no Size in Sqmm copper Aluminium

7 25 7 7

8 35 7 7

9 50 7 7

10 70 to 150 19 19

11 185 to 300 37 37

12 400 to 500 61 61

13 630 to 1000 91 91

Insulation

XLPE cables use specially made from high-grade cross-linked polyethylene for insulationby extrusion process.

OPERATING CHARACTERISTIC

Max. Conductor temp. for continues operation 90 deg CAmbient air temp. 40 deg CStandard ground temp. 30 deg CThermal resistivity of soil 150 deg C Cm/WThermal resistivity 350 deg C Cm/WDepth of laying 75 CmMinimum bending radius 12D

Max. Conductor temp. during SC 250 deg CMaximum ambient,air temp 85 deg C

LT-XLPE Main features

Longer life as compared to conventional PVC cables

Higher conductor temperature rating i.e. 90 deg C

Higher emergency overload capacity 120 deg C

Max. temperature limit under short circuit conditions for LT-XLPE cables is 250deg C

Insulation resistance is excellent & superior to identical PVC cables.

High corrosion resistance in polluted atmosphere.

Better properties of resistance to chemical and corrosive gases.

Low installation cost because of lightweight, dimension and are far more flexible.

Better properties to withstand vibrations, hot impacts.

Jointing of cables is easier and quicker.


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Inspection

All cables shall be inspected upon receipt at site and checked for any damage duringtransit and shall be supplied with complete manufacturers test certificates. At any costthe cables shall not be accepted without test certificate.

Storing

All the cables shall be supplied in drums, with manufacturers seal. On receipt of cablesat site, the cables shall be inspected and stored in drums with flanges of the cable drumin vertical position.

Joints in Cables

The Contractor shall take care to see that all the cables received at site are apportionedto various locations in such a manner as to ensure maximum utilization and avoidance ofcable jointing. This apportioning shall be got approved by the Consultant before thecables are cut to lengths.

Where joints are unavoidable, the Consultant shall be approved the location of suchjoints and marking shall be done with suitable tags.

TESTING OF CABLES

TESTS

The cables shall be tested in accordance with the IS: 694/1554/7098. The tests shallinclude

PVC insulated cables (for voltage up to 1100V:IS 694

PVC insulated cables (heavy duty): IS 1554 Part I.

Cross-linked polyethylene insulated PVC sheathed cables: IS 7098 Part I.

Cable Insulation Tests shall be conducted between phases and between phase andearth for each length of cable, before and after jointing. As such all phase cables maybe checked before being laid for above tests. On completion of cable laying work, thefollowing tests shall be conducted in the presence of the Consultant/Employer.


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Construction tests

Test for conductor and compaction. For copper conductor:

1. Persulphate test for tinned copper only2. Annealing test

Test for aluminium conductor:1. Tensile test2. Wrapping test3. Annealing test4. Resistance test for both copper and aluminium

Test of eccentricity of insulation.

Test for thickness of insulation

Test for laying up along with Polypropylene tape and fillers.

Virgin material test for PVC insulation.

Test for thickness of inner sheath

Test for armouring and armour coverage which should be more than 95%

Test for thickness of outer sheath

Insulation Resistance Test (sectional and overall)

Continuity resistance test.

Sheathing continuity test.

Cable size, sequential and manufacturers identification marking on the outer sheath.

Earth test.

All tests shall be carried out in accordance with relevant Indian Standard Code ofPractice and Local Electricity Rules. The Contractor shall provide necessary instruments,equipment and labour for conducting the above tests and shall bear all expenses inconnection with such tests. All tests shall be carried out in the presence of theConsultant/Employer.

CABLE TRAYS, ACCESSORIES AND TRAY SUPPORTS

Cable racks / trays shall either be run in concrete trenches or on overhead supports,supported from building steel, floor slab etc.

Cables shall be clamped to the cable trays at regular intervals.


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CONDUITS, PIPES AND DUCTS

The Contractor shall supply and install conduits, pipes and ducts as per requirement. Allaccessories / fittings required for making the installation complete, including but notlimited to, ordinary and inspection tees elbows, checkouts, male and female reducersand enlarges, wooden plugs, caps, square headed male plugs, nipples, gland sealingfittings, junction boxes, pull boxes, conduits, outlet boxes, splice boxes, terminal boxes,glands, gaskets and box covers, saddles and all steel supporting work shall be suppliedby the Contractor. Conduit fittings shall be of the same material as the conduits.

Flexible metallic conduits shall be used for termination of connections to equipment suchas motors or other apparatus to be disconnected at periodic intervals. Flexible metallicconduits shall also be used for termination of connections to level switches, levelelectrodes, limit switch, pressure, pressure switches etc.

Conduits or pipes shall run along walls, floors, and ceilings, on steel supports, embeddedin soil, floor, wall or foundation, in accordance with approved layout drawings.

Exposed conduit shall be adequately supported by racks and clamps or straps or byother approved means. Conduit supports shall be erected square, and true to line andgrade with an average spacing of one support for every 2 meters of conduit length.

Each conduit run shall be marked with its designation.

All installed conduits shall have their ends temporarily closed by caps, wooden plugs, orother approved means until cable is pulled. Closures shall be made in such a way thatthey do not get dislodged easily.

When one or more cables are trained through a conduit, conduit size shall be such that

the total cross sectional area of the cable does not exceed 60% of the internal crosssectional area of the conduit.

The Contractor shall be responsible for boning of metal pipes or conduits in which cableshave been installed to the main earthing system. Joints, metal sheath and armour ofcables shall be bonded to the earth system in an approved manner. The entire systemof conduit after installation shall be tested for mechanical and electrical continuitythroughout and permanently connected to earth by means of a special approved type-earthing clamp efficiently fastened to the conduit. Gas or water pipes shall not be usedas an earth medium.


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10. GENERAL REQUIRMENT OF CABLING SYSTEM

GENERAL

The cabling system covers the design as per relevant national / international

standards. It shall be responsibility of contractor to work out a detailed layout for the

complete plate cable system. The layout drawing shall be furnished for the approval

of Engineer before commencement of installation including cable trays, cable trays,

cable racks, accessories, tray supports, conduit etc.

CABLE LAYOUT

The following points shall be noted while planning cabling system for the plant

Inside the building either cable tray or cable trench shall be planned as per cabling

requirement.

Laying of Cables

Cables shall be laid as per the specifications given below:

Cables - Outdoor Trenches

Cables shall be laid in outdoor trenches wherever called for. The depth of the trenchesshall not be less than 900 mm (11KV) and 1050mm(22 & 33KV), below the final ground

level. The width of the trenches shall not be less than 450 mm. However, where morethan one cable is laid, a coaxial distance of not less than 150 mm shall be allowedbetween the cables. The trenches shall be cut square with vertical sidewalls and withuniform depth. Suitable shoring and propping may be done to avoid caving-in of trenchwalls. The floor of the trench shall be rammed level. The cables shall be laid in trenchesover rollers placed inside the trench.

The cable drums shall be laid unrolled in the direction of the arrow marked on the drumfor unrolling.

Wherever cables are bent, the minimum-bending radius shall not be less than 12 timesthe diameter of the cable. After the cable is laid and straightened, it shall be coveredwith 80 mm thick layer of sand. The cable shall then be lifted and placed over the sandcushion. Over this, 300 mm thick layer of sand shall be covered and a course of cableprotection tiles or RCC troughs shall be provided to cover the cables by 50 mm on eitherside. Remaining trench shall be backfilled with earth and consolidated as original.Cables shall be laid in hume pipes/stoneware pipes at all road crossings and in GI pipeat the wall entries. Cable route markers to be provided as per standards.

Excess debris shall be removed from site with free of cost


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Cables - Indoor

The cables laid indoors should be laid on slotted angle steel cable trays supported onM.S. angles. The cable trays should be routed above false ceilings wherever provided.

Suitable clamping with straps and saddles shall be used for keeping the cables inposition. Spacing between the cables shall not be less than the overall diameter of thecable.

The cables on wall surface from panel board up to angle iron shall run in galvanizedsteel pipes of adequate size.

The Cables run inside concrete trenches shall be supported on cable trays and shall beneatly arranged and clamped.

The Cable entries through pipes from outside to inside the building shall run in GI pipes

and shall be sealed water tight with approved type of sealant to avoid water entering thebuilding.

LAYING OF CABLESCables shall be laid as per the specifications given below:

CABLES - OUTDOOR TRENCHES

Cables shall be laid in outdoor trenches wherever called for. The depth of the trenches

shall not be less than 900 mm (11KV) and 1050mm (22&33KV) , below the final ground

level. The width of the trenches shall not be less than 500 mm. However, where more than

one cable is laid, a coaxial distance of not less than 450 mm shall be allowed between the

cables. The trenches shall be cut square with vertical sidewalls and with uniform depth.

Suitable shoring and propping may be done to avoid caving-in of trench walls. The floor ofthe trench shall be rammed level. The cables shall be laid in trenches over rollers placed

inside the trench.

The cable drums shall be laid unrolled in the direction of the arrow marked on the drum for

unrolling.

Wherever cables are bent, the minimum-bending radius shall not be less than 12 times the

diameter of the cable. After the cable is laid and straightened, it shall be covered with 150

mm thick layer of sand. The cable shall then be lifted and placed over the sand cushion.

Over this, 450 mm thick layer of sand shall be covered and a course of cable protection tilesor burnt brick shall be provided to cover the cables by 50 mm on either side. Remaining

trench shall be backfilled with earth and consolidated as original. Cables shall be laid in

hume pipes/stoneware pipes at all road crossings and in GI pipe at the wall entries. Cable

route markers to be provided as per standards

Excess depress shall be removed from sit at free of cost


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INSTALLATION OF CABLES

(a)The contractor shall install, test and commission the cabled specified in the technicalspecification in accordance with Contractors drawings and approved by the Engineer.

Cables shall be laid directly buries in earth, or cable racks, in build up trenches, on cabletrays and supports, in conduits and ducts or bare on walls, ceiling etc. as per approveddrawing. Contractors scope of work includes unloading, laying, fixing, joining, bending, andterminating of the cables. The Contractor shall also supply the necessary materials andequipment required for joining and terminating of the cables.

All apparatus, connections and cable work shall be designed and arranged to minimizerise of fire and any damage, which might be caused in the event of fire. Wherever cablespass through floor or wall openings or their partitions suitable bushes of an approved typeshall be supplied and put into position by the contractor. If required by the Engineer, theContractor shall seal the cables into the bushes using fire-resisting materials to prevent thespreading of fire through each partition.

Inspection on receipt, unloading, storage and handling of cables shall be in accordancewith IS: 1255 and other Indian Standard Codes of Practice.

Standard cable grips and reels shall be utilized for cable pulling. I unduly difficult pullingoccurs, the Contractor shall check the pull required and suspend pulling until furtherprocedure has been approved by the Engineer. The maximum pull tension shall not exceedthe recommended value for the cable measured by the tension dynamometer. In general,any lubricant that does not injure the overall covering & does not set up undesirableconditions of electrostatic stress or electrostatic charge may be used to assist in the pullingof insulated cables in conduits and ducts.

After pulling the cable, the Contractor shall record cable identification and date pulledneatly with waterproof ink on linen tags and shall securely attach such identification tags.Identification tags shall be attached to each end of each cable with non-corrosive wire. Thesaid wire must be non-ferrous material on single conductor power cable. Tags may furtherbe required at intervals on long runs of cable son cable trays and in pull boxes. Cable andjoint markers and RCC warning covers shall be provided wherever required.

Sharp bending and kinking of cables shall be avoided the bending radii for various typesof cables shall not be less than those specified below:

I.11 kV XLPE Multicore armoured cables: 15 times the overall dia of the cable.

II.650/1100V XLPE insulated cable. : 10 times the overall dia of the cables.

If shorter radius appears necessary, no bend shall be made until clearance andinstructions have been received from the Engineers Representative.

Power and control cables shall be laid in separate cable racks/trays.


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Where groups of HV, LV and control cables are to be laid along the same route, suitablebarriers to segregate them physically shall be employed.

When power cables are laid in the proximity of communication cables, minimumhorizontal and vertical separation between power and communication cables shall benormally 600mm, but in any case not less than 450mm for single core cables and 300mm for

Multicore cables. Power and communication cables shall as far as possible, cross at rightangles to each other.

Where cable cross roads and water, oil, gas or sewage pipes, the cables shall be laid inreinforced spun concrete or steel pipes. For road crossings the pipe for the cable shall beburied at not less than one meter depth

Cable laid in ground shall be laid on a 50mm riddled earth bed. The cables shall then becovered on top and at their sides with riddled earth to a depth of about 150mm. This is thengently up to a depth of about 100 mm above the top of uppermost cable covers which areplaced centrally over the cables. The protective cable covers for LV cables may be ofearthenware and for HV cables of reinforced concrete. The specification of protective covers

shall be generally as per Appendix C of IS: 1255. the RCC covers shall have one hole ateach end, to tie them to each other with GI wires to prevent displacement. The trench is thenback filled with the excavated soil and well rammed in successive layers of not more than300 mm in depth, with the trenches being watered to improve consolidation wherenecessary. To allow for subsidence, it is advisable to allow a crown of earth not less than 50mm in the center and tapering towards the sides of the trench.

Each cable shall be pulled into the particular conduit and shall be taken from theparticular reel designated for the run. All cables shall be neatly trained without interlacing. Inhand holes, pull boxes or junction boxes having any dimension over 1000mm, all conductorsshall be cabled and/or racked in an approved manner care shall be taken to avoid sharpbending or stressing cable beyond manufacturers recommendations in pulling. Cable shall

be protected at all times from mechanical injury and from absorption of moisture atunprotected ends.

In each cable run some extra length shall be kept at a suitable point to enable on or twostr

technical specifications for electrical work

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