specification no.:- ti/spc/psi/2x25/fc&sr/0100(...

Specification No.

TI/SPC/PSI/2x25/FC&SR/0100(……/10) Effective from:

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SPECIFICATION No.:- TI/SPC/PSI/2x25/FC&SR/0100(…/10)

GOVERNMENT OF INDIA

MINISTRY OF RAILWAYS

TECHNICAL SPECIFICATION FOR

SHUNT CAPACITOR & SERIES REACTOR EQUIPMENT TO BE USED OVER 2 X 25 KV TRACTION SUBSTATIONS

September’ 2010

ISSUED BY

TRACTION INSTALLATION DIRECTORATE RESERARCH DESIGNS & STANDARDS ORGANISATION

LUCKNOW – 226 011

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SPECIFICATION FOR: SHUNT CAPACITOR & SERIES REACTOR EQUIPMENT TO BE USED OVER 2 X 25 KV TRACTION SUBSTATIONS

SPECIFICATION No : TI/SPC/PSI/2x25/FC&SR/0100(…/10)

Amendment Number

Amendment / Revision Total pages Date of Issue

0 Re-affirmed Specification …..

PREPARED BY CHECKED BY APPROVED BY

SIGNATURE

DATE

DESIGNATION SE/TI DIR./TI-P&S ED/TI

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SPECIFICATION FOR

SHUNT CAPACITOR & SERIES REACTOR EQUIPMENT TO BE USED OVER 2 X 25 KV TRACTION SUBSTATIONS

SPECIFICATION NO. TI/SPC/PSI/2 x25/FC&SR/0100(…./10)

1. SCOPE 1.1. This specification covers design, manufacture, supply, testing and commissioning of shunt

capacitor equipment intended for outdoor installation on the 2 X 25 kV side of ac traction system on Indian Railways, for the purpose of improvement of power factor and reduction of maximum demand. It supersedes specification No. ETI/PSI/126(8/89).

1.2. This specification is technically similar to RDSO specification for Fixed capacitor and series reactor No. TI/SPC/PSI/FC&SR/0100.

1.3 The capacitor equipment shall be complete with control gear, protective relays, series reactors

and accessories necessary for its efficient operation. 1.4 All such items and accessories shall be deemed to be within the scope of this specification

whether specifically mentioned herein or not. The equipment shall be erected by the successful tenderer, therefore, the offer shall include deputing of engineers and supervisors by the supplier of equipment for adequate handling, installation, testing and commissioning to the satisfaction of Railway’s engineers at site.

1.5 All civil engineering works connected with foundations of the capacitor banks, circuit breaker,

isolator, series reactor, current & potential transformers, supporting steel structures for the equipment etc shall also be done by the contractor.

1.6 All associated items of HT shunt capacitor bank assembly like Series reactor, CT, PT, LA, CB,

isolators, protection relays & panels etc. should be procured from RDSO/CORE approved vendors.

2. GOVERNING SPECIFICATIONS 2.1 The shunt capacitor and associated items shall, unless otherwise specified herein, conform to

the latest revision of RDSO specification, Indian Standard specifications/IEC, Recommendations as indicated below and the Indian Electricity Rules, wherever applicable.

1. IS:513 Cold rolled carbon steel sheets.

2. IS:800 Code of practice for use of structural steel general building construction.

3. IS:1554 (Pt.II) PVC insulated (heavy duty) electric cable Pt.II for voltage above 1 kV.

4. IS:2099 Bushings for alternating voltages above 1 kV.

5. IS:13925 (1998) Shunt capacitor for AC power systems.

6. IS:3070 (Pt.-I) Lightning arrestor for ac systems, non-linear resistor type.

7. IS:3231 Electrical relays for power system protection

8. IS:5553 (Pt-3) Current limiting reactors and neutral earthing reators.

9. IS:5553 (Pt.-5) Tuning reactors.

10. IS:11298 (Pt.-3/Sec.1) Plastic films for electrical purpose: polypropylene films for capacitors.

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12. IS:12672 Internal fuses and internal over pressure disconnectors for shunt capacitors.

13. IEC 60871-1& IEC 60871-2 Shunt capacitor for ac systems having a rated voltage above 660V (part 1&2)

14. RDSO Specn. No.ETI/OHE/13(4/84)

Specification for hot-dip zinc coating on steel, masts, tubes and fittings, used on 25kV ac OHE

15. RDSO specn. No. ETI/OHE/18(4/84)

Specification for steel and stainless steel bolts, nuts and washers.

16. RDSO specn. No. TI/SPC/PSI/PROTCT/6070

Control and relay panel incorporating numerical type protection relays for 25kV ac traction substations.

17. RDSO specn. No.TI/SPC/PSI/MOGTLA/0100(07/10)

Metal oxide gapless type lightning arrestors.

19. RDSO Code NO.ETI/PSI/120(2/91)

Code of practice for earthing of power supply installation for 25 kV a.c., 50 Hz. Single phase traction system.

2.1.1 In addition to above, the following RDSO specifications are presently used for various equipment

being provided over 2 x 25 kV AT feeding system. Some of the specifications mentioned below are under revision therefore purchaser shall provide the latest specifications for below items which shall have to be adhered to by the tenderer for execution of the work

1 ETI/PSI/122(3/89) Specification for 245/145/123/72.5 kV double pole and triple pole isolators.

2 ETI/PSI/123(9/93) 21.6 MVA, 220/132/110 / 66 kV/2x27 kV, single phase, 50 Hz Traction power transformer for ‘AT’ feeding system

3 ETI/PSI/124(7/95) 54 MVA, 220/2x27 kV Scott-connected power transformer for 2x27 kV ‘AT’ feeding system.

4 ETI/PSI/125(7/97) 8 or 5 MVA, 2x27 kV 50 Hz, auto transformer for 2x27 kV ‘AT’ feeding system.

5 ETI/PSI/126(8/89) 25kV shunt capacitor equipment for 2x25kV ÀT’ feeding system.

6 ETI/PSI/127(8/89) Series capacitor equipment for 2x25 kV ÀT’ feeding system.

7 ETI/PSI/128(8/89) Resonance suppressing C-R device for 2x25 kV ÀT’ feeding system.

8 ETI/PSI/129(8/89) Distance relay for 2x25 kV ÀT’ feeding system.

9 ETI/PSI/130(8/89) Delta-I type fault selective relay for 2x25 kV ÀT’ feeding system.

10 ETI/PSI/132(8/89)

25 kV double pole outdoor, vacuum interrupters for Railway switching stations for 2x25 kV ‘AT’ feeding system.

11 ETI/PSI/133(8/89) 25 kV ac double pole isolators for 2x25 kV ‘AT’ feeding system.

12 ETI/PSI/135(8/89) ÀT’ Boost up current ratio type fault locator for OHE for 2x25kV ÀT’ feeding system.

13 ETI/PSI/138(8/89) Control and relay board for 2x25 kV ÀT’ feeding system.

14 ETI/PSI/139 (12/89) 25 kV ac double pole outdoor SF6 interrupters for 2x25 kV ‘AT’ feeding system.

15 ETI/PSI/141 (10/90) Static distance protection relay with parallelogram characteristic for 25kV ac single phase, 50 Hz traction overhead equipment.

16 ETI/PSI/145(3/92) Specification for 11 kV current transformer with ratio 500/5 for 2x25 kV ‘AT’ feeding system.

17 ETI/PSI/147(3/92) Specification for 25 kV current transformer with CT ratio 100-50/5 for shunt capacitor banks in 2x25 kV ‘AT’ feeding system.

2.2 Any deviation from this specification, proposed by the tenderer for improving the performance,

utility and efficiency of the equipment, will be given due consideration provided full particulars

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of the deviation with justification are furnished. In such case, the tenderer shall quote according to this specification and the deviations, if any, proposed by him shall be quoted as alternate/alternatives.

2.3 In case of any conflict between the contents of the above IS and this specification, the stipulation of this specification shall prevail.

3. ENVIRONMENTAL CONDITIONS.

3.1 The shunt capacitor installation shall be suitable for outdoor use in moist tropical climate and in areas subject to heavy rainfall, pollution due to industry and marine atmosphere and severe lightning. The limiting weather conditions which the shunt capacitor and associated items have to withstand in service are indicated below:

1 Atmospheric temperature i. Metallic surface temperature under Sun: 75° C max. and in shade: 55 C° max.

ii. Minimum temperature: - 10° C (Also snow fall in certain areas during winter season)

iii. Maximum ambient air temperature - 500C iv. Average ambient air temperature over a period

of 24 hours - 350C

2 Maximum relative humidity 100%

3 Annual rainfall Ranging from 1750 to 6250mm

4 Number of rainy days per annum

120 days

5 Maximum number of thunder storm days per annum

85 days

6 Maximum number of dust storm days per annum

35 days

7 Atmosphere during hot weather Extremely dusty and desert terrain in certain areas. The dust concentration in air may reach a high value of 1.6 mg/m³. In many iron ore and coalmine areas, the dust concentration is very high affecting the filter and air ventilation system.

8 Coastal area The equipments shall be designed to work in coastal areas in humid and salt laden atmosphere with maximum. pH value of 8.5, sulphate of 7mg per liter, max. concentration of chlorine 6 mg per liter and maximum conductivity of 130 micro siemens/cm.

9 Basic wind pressure 200kg/sq.m.

10 Altitude Up to 1000 m above mean sea level

3.2 VIBRATIONS

The shunt capacitor installation would also be subjected to vibrations on account of trains running on nearby railway tracks. The amplitude of these vibrations which occur with rapidly varying time periods in the range of 15 to 70 ms lies in the range of 30 to 150 microns at present with the instantaneous peak going up to 350 microns.

4. TRACTION POWER SUPPLY SYSTEM (2X25 KV AT FEEDING SYSTEM) 4.1 General Scheme :

The electric power for railway traction is supplied in ac 50 Hz. single phase through 2x25 kV AT feeding system, which has a feeding voltage from the substation two times as high (2x25 kV) as

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catenary voltage (25kV). This high voltage power supplied from the traction substation through catenary wire and feeder wire is stepped down to the catenary voltage by use of autotransformers installed about every 13 to 17 km along the track, and then fed to the locomotives, In other words, both the catenary voltage and feeder voltage are 25kV against the rail, although the substation feeding voltage between catenary and feeder is 50 kV. Therefore, the catenary voltage is the same as that of the conventional 25 kV system.

4.1.1 Since the power is supplied in two times higher voltage, the 2x25 kV AT feeding system is suitable for a large power supply, and it has the following advantages, compared with conventional feeding systems.

(a) Less voltage drop in feeder circuit. (b) Large spacing of traction substation. (c) Less telecommunication interference by use of AT installed with adequate spacing.

4.1.1 4.1.2 The power is obtained from 220/2x25 kV Scott- connected or V- connected traction

transformer or 132/2x25 kV single phase transformers. The primary windings of the single phase transformers are connected to two or three phases of 132 kV, three-phase effectively earthed transmission net-work of the Electricity Board, in case of a single phase transformer or in case of two single phase transformers connected in V, respectively. On the other hand, the primary windings of the Scott-connected transformers are connected to the three phases of 220 kV three-phase, effectively earthed transmission net-work of the Electricity Board. The Scott-connected transformer and V-connected single phase transformers are effective in reducing voltage imbalance on the transmission net-work of the Electricity Board . The spacing between adjacent substations is normally between 70 to100 kms. A power supply diagram No. ETI/PSI/SK/3 & a sketch showing the general arrangement at a traction sub-station is at Appendix-I & II

4.1.3 One outer side terminal of the secondary windings of traction transformer is connected to the

catenary, the other outer side terminal being connected to the feeder. Two inner side terminals are, via series capacitors or directly, connected to each other, and their joint is solidly earthed and connected to the traction rails.

4.1.4 The load current from the substation flows through the catenary and returns to the substation

flows through the feeder. Between two adjacent ATs, the load current fed from the catenary to the locomotive flows in the rail and is boosted up to the feeder through the neutral tap of ATs at left and right sides of the locomotive.

4.1.5 At the points of substation and sectioning post, a dead zone known as neutral section is

provided in OHE to avoid a wrong phase coupling. The power to the catenary and feeder on one side of the substation is fed by one feeder circuit breaker, even if there exist two breakers for one side, and each track is controlled by an interrupter. The two breakers are used as a stand-by for each other. For maintenance work and keeping the voltage drop within limits, one or more sub-sectioning and paralleling posts (known as SSP) are introduced between traction substation and a sectioning and paralleling post (known as SP). A SSP on a double track section normally has four sectioning interrupters and one paralleling interrupter. In case of fault, the feeder circuit breaker of the substation isolates it.

4.1.6 A figure showing the principle of AT feeding system and a typical power supply diagram showing

the general feeding arrangement at a traction substation and sections of the OHE are given in the sketch at the Appendix-V.

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4.2 PROTECTION SYSTEM 4.2.1 The following relays are provided for the protection of traction transformers:

a) Differential protection. b) IDMT over current protection, (on HT& LT side) c) Restricted earth fault protection, (on HT & LT side) d) Instantaneous over current element on HT side e) Phase-failure relay (to detect a malfunction of a feeder circuit breaker)

4.2.2 The following relays are provided for the protection of OHE:

a) Distance protection Module comprising of protection against wrong phase coupling, PT fuse failure and auto reclosure.

b) Instantaneous over current protection c) Delta-I type high resistance fault relay d) Under voltage relay

4.3 2 x 25kV OHE & Traction transformer – Electric Parameters:

The OHE is made up of a stranded cadmium copper catenary of 65 sq. mm or a stranded aluminum alloy catenary of 116 sq. mm and a grooved contact wire of 107 sq. mm making up a total of 150 sq. mm or 140 sq. mm copper equivalent, respectively. As a feeder wire, a stranded aluminum alloy of 240 sq. mm. is used. The calculated OHE impedance value of AT feeding circuit (OHE: Al 116-Cu 107 sq. mm. Feeder wire: Al 240 sq. mm) for a single track line is 0.0601 + j 0.1419 ohms/km (at25kV system impedance).

4.3.1 Traction transformer

The percentage impedance of a 2x25 MVA, 220/2x25 kV Scott- connect or V- connected transformer and a 20 MVA, 132/2x25 kV single-phase transformer are 12% ( at 27 MVA base) and 12% (at 21.6 MVA base), respectively.

4.3.2 Clearance at Substations:

Normally a minimum clearance of 500 mm is provided between any live part at 25 kV and earth. 4.4 Nature of faults on the OHE System 4.4.1 OHE is subjected to frequent earth faults caused by failure of insulation, snapping of OHE and

touching the rail or earth, or loose wires carried by birds coming in contact with OHE below over-line structures, miscreant activities etc. These faults are cleared by the feeder circuit breaker which operates on any one or both of the following relays depending on the proximity of the fault.

1. Distance relay 2. Delta I type fault selective relay 3. Instantaneous over current relay

4.4.2 Inadvertent coupling of two phases between adjacent substations at the neutral section or at

intermediate switching stations in case of extended feed, causes short circuit. This is cleared by tripping of one of the feeder breakers at the two ends through “Wrong phase coupling relays”

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4.5 Short Circuit level :

The source impedance for different grid supply voltages based on a three phase symmetrical short circuit level are generally between 2000 and 10000 MVA depending upon the proximity of the traction substation to the generating station. The actual values of fault levels which are depending upon the location of the traction substation shall however be furnished by the Railways in the particular specification attached with the tender papers.

4.6 Nature of load on the 2x25 kV system : 4.6.1 Traction load is of frequent and rapidly varying nature and may fluctuate between no-load and

overloads. The system is also subject to frequent short circuits due to earth faults. It is difficult, therefore, to forecast precisely the load cycle of traction service because of the non-uniform pattern of traffic, which is different on different days.

4.6.2 The conventional AC electric locomotives are fitted for conversion of ac to dc, with single phase bridge-connected silicon rectifiers with smoothing reactor for feeding the dc traction motors. The ripple current is in the region of 25 to 40%, which introduces harmonics in the 25kV power supply. There are some locomotives based on thyristor control, which are having higher harmonics generation. The typical percentages of harmonics present in the traction current with diode rectifier and the Thyristor locomotives are as follows :

Current harmonics (%) with

Rectifier Thyristor

3rd harmonics (150 Hz) 15% 23%

5th harmonics (250 Hz) 6% 14%

7th harmonics (150 Hz) 4% 10%

These are the typical values and measurements have indicated that these can be higher at lower loads and lower at higher loads.

4.6.3 The average power factor of electric traction and multiple unit trains generally varies between

0.7 and 0.8 lagging without compensation.

4.6.4 In big yards and loco sheds, a number of locomotives stand idle with only the load of their auxiliaries drawing higher reactive power. The load power factor is, therefore, rather low.

4.6.5 In addition to above IR is having locomotives and EMU’s fitted with 3-phase drives having regenerative braking capabilities.

5. TECHNICAL SPECIFICATION 5.1 Rating and other particulars

The capacitor bank installation shall be designed for the following ratings and other particulars. i) System - 2x2kV AT Feeding system ii) Nominal system voltage - 25kV (phase to earth) ii) Possible variation in the - 19.0 to 27.5 (Sometimes touching30kV) traction supply voltage iii) Equipment voltage class - 52 kV iv) Rated frequency - 50 Hz ± 3% v) Average power factor of the - Between 0.7 and 0.8 lagging (the exact

traction system value to be indicated in the tender)

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vi) Desired power factor after - 0.9 lagging installation of the capacitor bank

vii) Harmonics in the system - Please see clause 4.7.2 viii) The Standard ratings of HT capacitor bank and reactor shall be as under:

5.1.1 The complete HT capacitor bank (with 13% series reactor) shall have to be designed in two

exactly similar parts. One bank shall be between traction wire and rail (earth) while other bank shall be connected between Feeder wire and the rail. As minimum standard capacitor bank rating with 5, 220 kVAR and 8 kV capacitor units comes to 1100 kVAR @ 40 kV, minimum rating of a HT capacitor bank shall be 2200 kVAR (@ 40kV) and in multiples of it thereof. Refer to Appendix -III for constitutional of shunt capacitor equipment.

Capacity of bank in kVAr

at 40 kV

Xc(Ω) XL(Ω) Xc’(Ω) Capacity of bank in kVAr

at 25 kV

I at 25 kV (in Amps)

Rated current of reactor (in

Amps)

In the multiple of 220 kVAr

KV2 x 1000 kVAr

0.13 x Xc 0.87 x Xc KV2 x 1000 Xc’

KVAr at 25 kV 25

I at 25 kV x 1.3

2200 727.27 94.55 632.73 988 39.51 51

4400 363.64 47.27 316.36 1976 79.02 103

6600 242.42 31.52 210.91 2963 118.53 154

8800 181.82 23.64 158.18 3951 158.05 205

Note: Losses of the reactor shall be guaranteed at the rated current

NOTE: To cater for manufacturing tolerances of both capacitance and inductance, the maximum and

minimum frequencies shall be taken as 53 Hz and 47 Hz respectively. 5.2 Resonant condition and inrush current :

The rating of the capacitor bank shall be such that it does not resonate with source impedance including transformer impedance and series reactor (parallel resonance). It shall also not resonate with the series reactor (series resonance) at any of the harmonic frequencies. It shall also be ensured that the inrush current of the capacitor bank does not exceed the maximum guaranteed value. Calculations shall be furnished with the tender in respect of the inrush current, surge voltage and series/parallel resonant frequencies.

5.3 Capacitor Unit :

5.3.1 Rating of the capacitor unit of the bank shall be 220 kVAr, 8 kV. The individual capacitor units of

the bank shall be of All polypropylene (APP) self-contained, outdoor type provided with double bushing protected by internal element fuses. Each capacitor unit shall be built up of number of elements having a dielectric of plastic film (polypropylene) between the aluminium foils as electrode. The bushings shall be of porcelain and shall be jointed to the case by welding or other approved technique (except soldering). The minimum value of creepage distance for bushings shall be 25mm per kV of appropriate class. The bushing shall be in accordance with IS-2099-

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1986 & IS- 5621-1980 and shall be got routine & type tested from a reputed laboratory like CPRI, ERDA or another for which approval of RDSO may be obtained. The bushing shall also withstand a torsional effort at the terminal stud, not less than 20 Nm.

The capacitor elements shall be assembled in a stack closely fitted into the container in order to reduce the amount of free impregnation fluid. The container shall accommodate changes in fluid volume due to variation in the temperature. Each individual unit shall consist of a number of elements connected in series parallel arrangement. Each element shall be protected by means of an internal fuse connected in series. The capacitor unit shall be capable of withstanding transient over currents of high frequency and amplitude occurring at the time of their switching in the circuit. Each capacitor unit of 220 kVAr shall have at least 15 Parallel elements in each series group so that failure of 40% of elements in a series group shall not give rise to more than 10% over voltage on healthy parallel units. Each capacitor unit shall satisfactorily operate continuously at rated voltage and shall withstand 30% over current (rms value) due to over-voltages and harmonics. The unit shall also satisfactorily operate with traction harmonic currents as indicated in clause 4.7.2. Depending upon the actual capacitance value, which may be maximum of the 1.15 time the rated capacitance Cn, the maximum current may reach 1.5 times the rated current.

5.3.2 The Polypropylene film conforming to IS: 11298 shall be checked for proper thickness, roughness, breakdown voltage besides its physical appearance.

5.3.3 The capacitors shall be impregnated with non-PCB (Polychlorinated-Biphenyl) impregnation fluids which have excellent electrical characteristics, low toxicity, low bio-accumulation and are bio-degradable.

5.3.4 The aluminium foil used shall be of very high purity and free from materials like rolling oil and

such other defects. The thickness of aluminium foil used shall not be less than 5 microns. 5.3.5 The container of each capacitor unit shall be leak and moisture-proof. The capacitor containers

shall be made of CRCA steel sheets of drawing quality generally as per IS: 513. The nominal thickness of steel shall be 1.6 mm. The inside surface of the container in contact with the impregnating fluid shall not be painted and shall only be degreased and made rust-free. The steel surfaces exposed to weather shall be given a primer coat of zinc-chromate and two coats of light grey enamel paint as per shade 631 of IS: 5.

5.3.6 Internal element fuse for capacitor units shall comprise very high-grade quality special alloy

wire. The raw material for fuse shall comprise fuse wire, pressboard and insulating paper. These fuse wire shall be checked for tolerance in dimension and uniformity in finish and also for compatibility with the impregnating fluids. The element fuse shall be current limiting type, which shall operate in a very short duration to isolate the faulty elements.

5.3.6.1 The fuse shall be capable of carrying both nominal current continuously and inrush current. It

shall operate safely at the minimum available energy and should not explode while discharging maximum available energy.

5.3.6.2 The construction of the internal fuse shall be such that the residue of fuse operations shall not contaminate the impregnating liquid.

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5.3.6.3 The internal fuse shall be so designed that fuse operation under the worst conditions will not cause a fire inside the unit. The internal fuse shall be designed and tested as per IS: 12672 and test results furnished with each capacitor unit.

5.3.7 Each capacitor unit shall be provided with a directly connected internal discharge device to drain

the residual voltage from the crest value of the rated voltage to 50 volts or less within ten minutes of disconnection of the capacitor from the source of supply.

This device shall be made from carbon resistors without lacquer coating.

5.4 Series reactor (Harmonic suppression reactor) :

A series reactor shall be provided to limit the inrush current and surge voltage at the time of switching ‘ON’ of the capacitor bank. The switching surge voltage shall not exceed 70 kVp. The series reactor, which is also meant to filter a part of the harmonics generated by the traction loads shall have inductive reactance (XL) equal to or greater than 13% of capacitive reactance (XC) of the capacitor bank. The series reactor shall be non-shielded, outdoor type, natural air-cooled, air cored, dry insulated type. The reactor shall be rated for the maximum current including harmonic currents that would flow through the capacitor bank under operating conditions mentioned in Clause 4.7.2 The reactor shall be so designed that the variation in milli-henry value due to manufacturing tolerance is less than + 3% The maximum losses in the reactor under rated current shall be approximate to 5 kW ±10% for capacitor bank with kVAr ratings up to 5000 kVAr at 25 kV. The material composition of the reactor shall be aluminium. The reactor shall be tested for temperature rise test at maximum continuous current.

5.4.1 The successful tenderer shall provide complete system details of series reactor and HT capacitor bank e.g. KVAr, XL, XC, Current, Voltage etc. to the manufacturer of series reactor (OEM).

5.4.2 Reactors should be designed to facilitate easy lifting and provided with lifting eyes or similar provisions to allow safe & rapid installation.

5.4.3 Lifting and handling instructions shall be furnished by the reactor manufacturer. In case of heavy

reactors, special crating and transport precautions shall be taken by the reactor manufacturer to keep stresses in the reactor within safe levels.

5.5 Basic insulation level :

The basic insulation level of the complete capacitor bank and other associated equipments. i.e. shunt capacitor, circuit breaker, current & potential transformers, series reactor and isolator shall be as follows :

i) 1.2/50 microsecond impulse withstand voltage (peak) : 250 kV ii) One-minute wet power frequency withstand voltage (rms): 105kV

5.6 Protection : 5.6.1 The offer shall include design and supply of a comprehensive protection scheme for the

equipment offered by the tenderer. Full details including relay characteristics of the protection scheme offered for the capacitor bank, series reactor, circuit breaker shall be fully explained in the offer giving necessary calculations and diagrams.

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5.6.2 The protective relays offered shall be properly coordinated with the existing scheme of

protection indicated in sketch attached at Appendix-IV 5.6.3 The protection system for shunt capacitor bank shall include protection against over current,

overload, over voltage, under voltage and unbalance current protection.

i) Over current relay with inverse definite minimum time (IDMT) element with suitable settings.

ii) Over voltage relay – over voltage protection against system over voltages shall be provided with an inverse time characteristics with suitable settings. The over voltage relay shall be energized from a potential transformer connected to the main bus bar on the incoming side of the circuit breaker controlling the capacitor bank. If required an interposing voltage transformer (IVT) of suitable ratio shall be used for matching the capacitor over voltage withstand characteristics.

iii) Under voltage relay – In conjunction with the timer to enable the capacitors to discharge

before reclosure. The relay provided for this purpose shall be connected to the bus potential transformer and have high resetting ratio. Also a time delay relay shall be included with adjustable setting of 0 to 10 minutes to provide a time lag before the breaker can be reclosed. However, this relay would not be required if a timer is included in the closing circuit of its associated breaker to prevent its reclosing within 10 minutes.

iv) The capacitor bank shall be protected by means of unbalance current protection. The capacitor

bank shall be connected as a bridge and an unbalance sensing current transformer provided. The current transformer ratio shall be chosen so that even one capacitor element failure can be detected. The relay used shall be a harmonic insensitive over current relay with fixed time delay characteristic. The time delay shall be set at approximate 0.1 sec. Calculations shall be furnished to establish that unbalance protection shall operate before the over voltage limits as given in Clause No. 5.3.1 are exceeded.

v) Each capacitor element shall be protected by means of internal fuse. The fuse shall be

connected in series with each capacitor element inside the capacitor unit to limit the effects of dielectric failures. If a puncture of dielectric occurs, only one element shall be disconnected and the capacitor unit continues to operate. While selecting the fuse rating, it would be necessary to choose proper time-current characteristics which in turn significantly depends upon the cross section and circumference e of the fuse. Fuses chosen shall have adequate thermal capability and comply with relevant IS: 12672.

5.6.4. The tenderer may propose any other protection which they consider in their experience to be

superior for the installation and shall give full justification for the same.

6. General arrangement of capacitor bank and associated equipment

6.1 The capacitor bank shall be of outdoor type, mounted on steel rakes for connection to the 25kV bus through single pole isolator and circuit breaker. The capacitor bank shall consist of groups of individual capacitor units, connected in series-parallel combination to deliver the rated output, at normal rated system voltage, rated frequency and other system conditions detailed elsewhere. The number of parallel units in each series group shall be selected so as to satisfy the conditions in clause No. 5.3.1. the capacitor bank shall be supplied complete with mounting steel rack assembly, interconnectors between units, insulators, suitable earthing lugs including

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terminal connectors (but without connecting jumper to 25kV bus) and other material required to make the bank complete in all respects for its satisfactory operation.

6.2 Mounting arrangement 6.2.1 The capacitor bank and the series reactor shall be suitable for mounting on steel racs which in

turn shall be mounted on a concrete plinth with suitable base frames. The racks shall be complete with rack insulators and other hardware.

6.2.2 The tenderer is free to suggest any other arrangement for mounting the capacitor bank and reactor which is considered economical without sacrificing the safety of the personnel working in traction substation. Full details of such arrangements shall be furnished with the tender.

7. Control panel

The control panel having the relays for the capacitor bank shall be supplied and installed by the tenderer in the control room of unattended remote control traction substation as per RDSO specification No. TI/SPC/PSI/PROTCT/6070 or latest.

8. Current transformer and potential transformer:

Current and potential transformers for the protection of capacitor bank shall be supplied by the tenderer as per RDSO specification No. ETI/PSI/90(06/95) and TI/SPC/PSI/PTS/0990 respectively. However, in case of unbalance current protection, current transformer shall be of metering class. Full technical particulars of such transformers shall be furnished in the offer.

9. Protection against lightning surges:

A separate lightning arrestor shall be provided to protect the capacitor bank against lightning surges as per RDSO specification No. TI/SPC/PSI/MOGTLA/0100. The lightning arrestor shall be metal oxide gapless type 42 kV class having 10 kA discharge current. The lightning arrestor shall be designed to withstand the full energy discharge from the capacitor bank to which it is connected.

10. Earthing:

Earthing arrangements shall be provided for capacitor bank installation in accordance with RDSO Code No. ETI/PSI/120(2/91) Code practice for Earthing of power supply installation for 25kV, ac, 50 Hz, single phase traction system.

11. Painting:

All steel structures exposed to weather shall be given primer coat of zinc chromate and two coats of light grey enamel paint to shads No.631 of IS: 5. One additional coat of paint shall be given at site by the manufacturer.

12. Fasteners:

All fasteners of 12 mm diameter and less exposed to atmosphere shall be of stainless steel and those above 12 mm dia shall be preferably of stainless steel or mild steel hot dip galvanized to RDSO’s specification No. ETI/OHE/18(4/84). The material of the stainless steel fasteners shall conform to IS: 1570 (Pt.V) Grade 04 Cr 17Ni 12 Mo 2.

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13. Testing of capacitor equipment: 13.1 General: 13.1.1 Once a purchase order is placed for supply of capacitor equipment the designs and drawings

shall be furnished to the purchaser/Director General (Traction Installation) Research Designs and Standards Organisation , Lucknow, as the case may be within the period stipulated in the order. Only after all the designs and drawings have been approved for prototype tests and a written advice given to that effect, the successful tenderer/manufacturer take up manufacture of the prototype of the shunt capacitor equipment. It is to be clearly understood that any change or modification required by the above authorities is to be done in the prototype shall be done expeditiously, not withstanding approval having already being given for the designs and drawings. Such change or modification shall be incorporated in the drawing as indicated in clause 15.6.

13.1.2 Prior to giving a call to the Purchaser/Director General (Traction Installation) Research Designs and Standards Organisation, Lucknow, hereafter written as DGTI-RDSO for inspection and testing of the prototype the successful tenderer/manufacturer shall submit a detail test schedule consisting of schematic circuit diagrams for each of the test and the number of days required to complete all the tests at one stretch. Once the schedule is approved, the tests shall invariably be done accordingly. However during the process of type testing or even later, the purchaser reserves the right to conduct any additional test(s), besides those specified herein, on any equipment/item so as to test the equipment/item to his satisfaction or for gaining additional information and knowledge. In case any dispute or disagreement arises between the successful tenderer/manufacturer and representative of the Purchaser/ DGTI-RDSO, during the process of testing as regards the procedure for type tests and/or the interpretation and acceptability of the results of type tests, it shall be brought to the notice of the purchaser/ DGTI-RDSO, as the case may be, whose decision shall be final and binding. Only after the prototype shunt capacitor is complete and ready in each and every respect, shall the successful tenderer/manufacturer give the actual call for the inspection and testing with at least fifteen days notice for the purpose.

13.1.3 In the event of the test not being carried through to completion at one stretch for any reason attributable to the successful tenderer/manufacturer and it is required for the representative of the Purchaser/ DGTI-RDSO, to go again or more number of times to the works of the successful tenderer/manufacturer or other place(s) for continuing and/on completing the tests on the prototypes of the equipment, the successful tenderer/manufacturer shall reimburse to the purchaser/ DGTI-RDSO, shall be paid through a demand draft to the concerned account officer of the purchaser/ DGTI-RDSO, as shall be advised to the successful tenderer/manufacturer.

13.1.4 The following type tests shall be carried out on the prototype shunt capacitor equipment at the

works of the successful tenderer/manufacturer in the presence of the representative of the purchaser/ DGTI-RDSO and the tests for which facility does not exist at firms premises shall be conducted at a reputed testing laboratory in accordance with the relevant specifications and reports shall be submitted to RDSO.

13.2 Type tests on shunt capacitor equipment : 13.2.1 The following type tests shall be carried out on the prototype capacitor unit as per IS: 13925

(part-I): 1998 and shall be carried out in the sequence given below:

1. Test for output and capacitance (as per clause No.14) 2. Voltage test between terminals(as per clause No.16)

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3. AC Voltage test between terminals and container(as per clause No.17) 4. Measurement of tangent of dielectric loss angle(as per clause No.15)

The measured value of the dielectric loss angle. (tan δ) shall not exceed 0.0002 5. Test of discharge device (as per clause No.18) 6. Sealing test (as per clause No.19) 7. Thermal stability test (as per clause No.20)

The change in capacitance before and after the thermal stability test shall not exceed 2% 8. Capacitor loss tangent (tan δ) measurement at elevated temperature (as per clause

No.21) The measured value of the dielectric loss angle (tan δ) shall not exceed 0.0002

9. Lightning Impulse voltage test between terminals and container(as per clause No.22) and

10. Short circuit discharge test (as per clause No.23) The capacitance shall be measured before the capacitor discharge test and after the voltage test and the change in capacitance shall not exceed 2%

13.2.2 Special test on capacitor unit with internal fuses :

The special discharge test shall be performed to check the mechanical strength of internal fuses and discharge resistors with the capacitor unit as per the sequence given in the diagram:

1. Low voltage capacitance measurement. 2. DC Voltage test (4.3 Vn 10 sec.) 3. Direct discharge from 1.7 Vn. 4. Low voltage capacitance measurement. 5. Capacitance and loss measurement (Vn) (Vn=rated voltage of capacitor)

In addition to the above, voltage test (between terminals and case) and discharge resistor test shall also be carried out.

Note: Above tests as mentioned in clause No. 13.2.1 & 13.2.2 shall be repeated at the time of

renewal of vendor registration with RDSO. 13.3 Routine test on shunt capacitor:

The following test shall be carried out as routine tests and shall be carried out on each unit as per IS: 13925 (part-I): 1998:

1. Visual Examination (as per clause No.13) 2. Sealing test (as per clause No.19) 3. Test on output and capacitance (as per clause No.14) 4. Voltage test between terminals (as per clause No.16) 5. AC Voltage test between terminals and container (as per clause No.17) 6. Test of efficacy of discharge device (as per clause No.18); and 7. Measurement of tangent of dielectric loss angle (as per clause No.15).

13.4 Acceptance tests on shunt capacitor:

The routine and/or type tests or some of them may be repeated by the purchaser by mutual agreement between the purchaser and the manufacturer. The following acceptance tests on shunt capacitor shall be carried out as per IS: 13925 (part-I): 1998 and in the sequence given bellow:

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1. Visual examination (as per clause No.13) 2. Test on output and capacitance (as per clause No.14) 3. Voltage test between terminals (as per clause No.16) 4. AC Voltage test between terminals and containers(as per clause No.17) 5. Test for efficiency of the discharge device (as per clause No.18) 6. Measurement of tangent of dielectric loss angle (as per clause No.15) 7. Sealing test (as per clause No.19)

13.5 Endurance test :

This test shall only be carried out as a type test on the first prototype capacitor unit in accordance with the procedure laid down in IEC publication 871-2 and repeated if any changes will be made in design.

13.6 Type tests on series reactor:

13.6.1 The following type tests shall be carried out on the prototype units as per IS: 5553 (parts 3 &

5) and shall be carried out in the sequence given below:

1. Measurement of winding resistance 2. Measurement of insulation resistance 3. Measurement of Impedance at continuous current, 4. Measurement of loss 5. Separate source voltage withstand test, 6. Temperature rise test at rated continuous current, 7. Lightning impulse test. 8. Measurement of Q-factor

Note: Above tests shall be repeated at the time of renewal of vendor registration with RDSO.

13.6.2 Routine tests on series reactor :

The following routine test shall be carried out on each unit of series reactor as per IS:5553 (parts 3 & 5)

1. Measurement of winding resistance, 2. Measurement of insulation resistance, 3. Measurement of impedance at continuous current, 4. Measurement of loss, 5. Separate source voltage withstand test, 6. Induced over-voltage withstand test or lightning impulse test and 7. Measurement of Q-factor.

13.6.3 The Short time current test and measurement of impedance at short time current shall only be

carried out as a type test on the first prototype reactor unit in accordance with the procedure laid down in IS: 5553 (parts 3 & 5) and repeated if any changes will be made in design.

13.7 Test on control panel :

Following checks and tests shall be carried out on the control panel: i) Visual checks:

General check of control board in respect of construction, wiring, provision of various equipments and relays.

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ii) Operation tests: Operation tests on all the equipments, switches and tests to prove correctness of wiring of various circuits including indications, alarms, operation of relays and annunciation.

iii) Power frequency high voltage withstand test: Voltage test on the panel with all equipments and wiring for a withstand voltage of 2000V (rms) to earth for one minute.

iv) Insulation resistance tests: Measurement of insulation resistance of the complete panel wiring, circuit by circuit, by using 1000V megger.

13.8 Following tests shall be jointly conducted at site alongwith representative of Railways/purchaser

to verify the performance of the complete capacitor bank installation:

i) Rise in voltage due to capacitor bank connection: At different loads, the voltage at the 25kV busbar shall be recorded for 24 hours each with and without the capacitor bank. The rise in voltage due to the capacitor bank shall be assessed from these observations.

ii) Test on protection system: This test shall be carried out by simulating the faults conditions and observing the relay operation.

iii) Harmonic analysis: The harmonic analysis of current and voltage waveform shall be carried out by the tenderer with and without capacitor bank in circuit.

iv) Surge Voltage measurement: The surge voltage shall be measured by the tenderer at the time of switching in the capacitor bank. This shall be done for 20 times; the voltage peak shall not exceed 70 kVp in any case.

13.9 Schedule of pre-commissioning tests:

The schedule of pre-commissioning tests on the capacitor units, reactor and the complete bank, control & relay panels circuit breakers and other items shall be mutually agreed upon and between the successful tenderer and the purchaser.

13.10 The HT capacitor unit and series reactor shall be inspected by OEM before being commissioned. A certificate to this extent that the installation is fit for commissioning shall be taken from the Original Equipment Manufacturers.

14.0 Capitalization of losses:

In evaluating the offer, the price of capacitors and series reactor with higher watt losses/KVAr shall be compared by increasing the prices by capitalization of additional losses by the formula given in Appendix-VII. The tenderer shall for this purpose clearly indicate the losses in watts per kVAr rating of the capacitor bank and separately for the series reactor at rated voltage.

14.1 The losses of the capacitor bank shall be made up of the losses per capacitor unit (including

fuses and discharge device) multiplied by the number of units in the bank. The overall losses of a capacitor unit shall be as low as possible and shall not be more than 0.2 watt/KVAr.

15.0 Technical data and drawings:

15.1 The tenderer shall furnish guaranteed performance data, technical and other particulars for the equipments offered in the proforma at Annexure-A. Technical details of the protection

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employment together with detailed calculation or the ratings of the equipment shall also be furnished with the tender.

15.2 The information furnished in Schedule of guaranteed technical performance, data and other

particulars shall be completed in all respects. If there is any entry like “shall be furnished later” or blanks are left against any item, the tender is not likely to be considered as such omissions cause delays in finalizing the tender.

15.3 The tenderer shall specifically indicate in a statement attached with his offer, his compliance

with each clause and sub clause of this specification. If any vague remarks on any clause or sub-clause of this specification is given by the tenderer, then the tender submitted by him is not likely to be considered. A separate deviation statement shall be furnished with the offer drawing attention to the clause(s) where the tenderer seeks deviation giving detailed remarks/justification thereof. If there are no deviations, a ‘NIL’ statement shall be furnished.

15.4 The tenderer shall furnish the following calculations with their offer:

a) Detailed calculations for rating of capacitor bank, series reactor, inrush current, transient over voltage, parallel and series resonant frequencies.

b) Calculations for protection scheme offered. c) Calculations to establish that unbalance protection shall operate before the over voltage

limits as given in Clause 5.3.1 are exceeded. d) Calculations for design of supporting frame, fixing arrangement and foundation.

15.5 The successful tenderer shall be required to submit for approval the following detailed

dimensioned drawings as per Indian Railways Standard in sizes of 210mmx297mm or any integral multiples thereof: a. Outline general arrangement drawing of the capacitor bank installation indicating overall

dimensions, clearance and location of equipments/fittings (all the 3 views) name and rating plate with diagram of connections (one in English and the other in Hindi)

b. Outline general arrangement of series reactor including cross-sectional views in both plan and elevation; rating and diagram plate and core lifting arrangement.

c. Schematic and wiring diagram. d. Supporting frame with details of fixing arrangement and foundations along with calculation

for their designs. e. Arrangement of capacitor bank showing series reactor, circuit breaker, isolator, lightning

arrestor, current/ potential transformers. f. Details of capacitor bank showing series parallel arrangement of capacitor units. g. Arrangement of core winding and magnetic path of series reactor. h. General arrangement of circuit breaker showing mounting arrangement and overall

dimensions.

15.6 After approval of designs and drawings by Director General (TI), RDSO, Lucknow the tenderer shall manufacture an acceptable prototype of shunt capacitor equipment as per approval drawings. The prototype inspection shall be carried out by the representative of RDSO. The bulk manufacturing shall be taken up only after approval of prototype by Director General (TI), RDSO, Lucknow.

15.7 Routine inspection shall be carried out by the representatives of Indian Railways at the

manufacturer’s works.

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15.8 After approval, six copies of approved drawings along with two sets of reproducible prints shall be supplied to each consignee(s). Besides, two copies of drawings along with one set of reproducible prints and a soft copy in Auto-cad shall be supplied to Director General (Traction Installation), Research Designs and Standards Organisation. Lucknow (India).

15.9 The successful tenderer shall supply 10 copies of Instruction/Maintenance Manual for the

capacitor bank and series reactor installation and its fittings and accessories, to each consignee(s) and 2 copies to Director General (Traction Installation), Research Designs and Standards Organisation, Lucknow (India)

16. Additional Particulars:

The tenderer shall visit the traction sub-station location, if necessary, and collect any additional data/details required for the design of the capacitor bank and the series reactor/surge suppression equipment. It would be the responsibility of the tenderer to visualize the problems and understand the system conditions before evolving a suitable design.

17. Erection Testing and Commissioning:

17.1 The successful tenderer shall carry out the installation and commissioning of H T capacitor bank and series reactor under the supervision of competent engineers of the Original equipment Manufacturers (OEM) of HT capacitor bank as well as series reactor, which shall be subjected to the specified pre-commissioning tests at site in the presence of the Railway engineer. Necessary arrangement/ coordination in this regard shall be done by successful tenderer. For this purpose prior intimation regarding the date and location of the tests shall be given by the purchaser to the successful tenderer.

17.2 Proper packaging, handling & storage of the capacitor bank and reactor shall be ensured by the successful tenderer and manufacturer to avoid any damage to equipment during transportation, storage and installation at site. The successful tenderer shall fully adhere to handling instructions issued by manufacturer of capacitor/reactor and suitable capacity machinery shall be used for this purpose if required.

18. Spares:

The tenderer shall furnish along with his offer a list of spares, with cost, recommended by him for maintenance of capacitor bank installation for a period of 2 years.

19. Training of Indian Railways’ Engineers:

The offer shall include the training of two engineers or technicians of the Indian Railways free of cost at manufacturer’s works in India and at the traction substation of a railway system or other public utility where capacitor bank installations of similar/identical design are in operation. The total duration of training for each engineer/technician shall be 2 weeks of which approximately 1 week will be at the manufacturer’s works and 1 weeks on a railway system or other public utility. The cost of travel to the country of manufacture and back will be borne by the Indian Railways. Other details shall be settled at the time of finalizing the contract or purchase order.

20. Warranty:

Each HT capacitor bank including reactor and all equipment supplied against a purchase order/contract, in which this specification is quoted, irrespective of origin (imported or indigenous) shall be guaranteed for trouble free and satisfactory performance for a period of 42

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months from the date of supply or 36 months from the date of commissioning at the substation on Indian Railways, whichever period is shorter. Details of warranty/guaranty clause, the extent of responsibility on other relevant aspects shall be included in purchase order or contract. The tenderer shall furnish detailed terms and conditions in this regard in his offer.

21. The supplier shall supply Digital, portable battery operated capacitance meter with range of 200

p.f. to 2000 μF accuracy class 0.1% of full scale reading. Guaranteed for satisfactory operation for 18 months from the date of commissioning of the capacitor bank. One such unit shall be supplied for one capacitor bank location. The display shall be 0.5” LCD type 3-1/2 digit with minimum capability of one digital place reading space in decimal point for each range.

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Annexure to Specification No. TI/SPC/PSI/2X 25/FC&SR/0100(…/10)

SCHEDULE OF GUARANTEED PERFORMANCE TECHNICAL AND OTHER PARTICULARS. *****

‘A’ - Capacitor Unit

S.N. Description Unit of Measurement

01. Maker’s name

02 Country of manufacture

03 Manufacturer’s type designation

04 Location of capacitor bank (outdoor/indoor)

05 System voltage KV

06 Rated voltage of unit as per IS: 13925 KV

07 Maximum voltage (rms), which the capacitor unit can withstand continuously.

KV

08 Rated frequency Hz

09 No. of phases No.

10 Upper limit of temperature category Deg.C

11 Capacity of individual unit at rated voltage of unit. KVAr

12 Capacity of capacitor bank at 25 kV KVAr

13 i) Rated continuous current ii) Maximum continuous current including harmonics iii) Maximum inrush current at the instant of switching in.

Amps Amps Amps

14. Basic insulation level of unit a) Power frequency voltage withstand b) 1.2/50 microsecond impulse withstand voltage

KV(rms) KV(peak)

15. Basic insulation level of complete capacitor bank a) Power insulation voltage withstand b) 1.2/50 microsecond impulse withstand voltage

KV(rms) KV(peak)

16. Transient current withstand capacity. KA

17. Constructional details of capacitor unit. i) Dielectric material and its thickness

a) Tensile strength b) Percentage elongation c) Shrinkage d) Dielectric break down voltage

ii) Foil material and thickness iii) Impregnating liquid used and it’s properties.

a) Tan Delta b) Break down voltage c) Flash point d) Acidity e) Volume resistivity.

iv) Discharge resistors. v) Internal fuses

V/micron

18. Total max. losses per kVAr/unit at rated 25 kV voltage and rated 50 Hz frequency (In accordance with clause 14.2)

Watts

19. Capacitor Unit i) No. of elements in series ii) No. of elements in parallel

No. No.

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20. Capacitor bank i) Capacitance of bank ii) No. of series groups iii) No. of parallel units in each group

Micro Farad No. No.

21. Internal fuse i) Type of internal fuse elements of capacitor unit ii) Length of fuse element iii) Cross section of fuse element iv) Circumference of fuse element v) I 2t characteristics. vi) Time factor (t) of internal fuse element

mm sq.mm mm Sec.(under max. energy condition) Sec. (under Min. energy condition)

22 Discharge device. i) Type ii) Location iii) Time interval between de-energisation and re-energisation. iv) Residual voltage after an interval of 10 minutes of de-

energisation

Minutes. Volts.

23 Bushings: i) Maker’s name ii) Governing specification iii) Wet-1 minute power frequency voltage withstand. iv) Impulse voltage withstand 1.2/50 micro-second full wave. v) Creepage distance in air vi) No. of bushings in each unit

KV(rms) KV(peak) Mm No.

24. Overall dimensions i) Capacitor Unit ii) Complete capacitor bank

25 Weight per unit Kg.

26. Weight of the complete bank. Kg.

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’B’ Control and Relay panel.

1. Name of manufacturer and address 2. Overall dimensions and weight L - mm W - mm H - mm Weight- kg 3.

i) Color of the panel ii) Color of the mimic

4. Details of switches provided and their make. 5. Annunciations provided. 6. Size of wires used for:

i) Control circuit ii) Indication circuit. iii) General wiring. iv) Potential and current transformer circuits v) Heating circuit vi) Light circuit

7. Method of cable entry. 8. Details of instruments, if any, provided.

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‘C’ Protective Relays for Capacitor Bank

a) Over-current protection

i) Type and make of relays offered. ii) Setting range of current available.

b) Over-voltage protection

i) Type and make of relay offered. ii) Setting range available.

c) Unbalance Protection

i) Setting range available on current operated relay. ii) Calculations to show over voltage on other capacitor units due to successive element

failures. iii) Details (Type , Make and setting range) of current operated relay. iv) Values of unbalance currents at which alarm & trip signals shall be given.

d) Under Voltage protection

i) Type and make of relay used. ii) Resetting ratio of the under voltage relay. iii) Type and Make of the time delay relay. iv) Setting range of the undervoltage relay. v) Setting range of the time delay relay.

NOTE : This tenderer should be complete with three sets (one with each copy) of technical literature and pamphlets of the relay used.

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‘D’ Series Reactor

S.N. Description Unit of Measurement

1. Name of manufacturer and country

2. Governing specification

3. Type of reactor

4. Rated system voltage KV

5. Rated voltage KV

6. Rated current A

7. Maximum continuous current including harmonics A

8. Rated kVAr KVAr

9. Rated frequency Hz

10. Inductance of series reactor mH

11. Rated impedance Ohms

12. Parallel & Series resonant frequencies of the system Hz (Parallel) Hz(Series)

13. Class of insulation

14. Maximum temperature rise: - i) At continuous current ii) At 130% loading

Degree C Degree C

15. Basic insulation level: - i) Power frequency voltage withstand ii) 1.2/50 microsecond impulse withstand voltage

KV(rms) KV(Peak)

16. Value of the peak surge voltage generated at the time of switching in of shunt capacitor (calculations shall be appended)

KV

17. Rated inrush current A

18. Short time current and specified duration KA

19. Designed Q-factor at a specified frequency.

20. Overall dimensions of the series reactor mm x mm x mm

21. Total weight of the series reactor Kg.

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‘E’ – Instrument Transformers (a) CURRENT TRANSFORMER:

S.N. Description Unit of measurement

1. Name of the manufacturer and country

2. Governing specification’

3. Manufacturer’s type designation


5. Rated primary current A

6. Rated secondary current A

7. Rated frequency Hz

8. Rated burden VA

9. Rated transformation ratio

10. Accuracy class

11. Rated accuracy limit factor

12. Current error at rated primary current %

13. Phase displacement at rated primary current Minute

14. Composite error at the rated accuracy limit primary current %

15. Rated short time thermal current (for one second) KA(rms)

16. Temperature rise with rated load and with specified overload over a maximum ambient air temperature of 50 degree C. a) of oil by thermometer b) of winding by resistance (secondary)

Degree C Degree C

17. Porcelain housing a) Name of manufacturer b) Governing specification c) Voltage class d) Rated current e) Minimum creepage distance in air f) Weight

KV A mm Kg

18. Core particulars a) Type of core b) Maximum flux density at rated primary current c) Minimum knee point (emf) voltage d) Exciting current at knee point (emf) voltage

T V

19. Winding particulars a) Type of primary winding b) Current density in primary winding at rated current c) Resistance of secondary winding at 75 deg.C d) Class of insulation

i) Primary winding ii) Secondary winding

20. Overall dimensions of CT: Height Length Breadth

mm mm mm

21. Total weight of CT Kg

22. a) Is the CT of sealed construction with nitrogen gas at the top? b) Pressure or amount of Nitrogen gas. c) Pressure relief device provided or not.

Yes/No

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b) POTENTIAL TRANSFORMER

1. Name of the manufacturer & country

2. Governing Specification

3. Manufacturer’s type designation


5. Rated frequency VA

6. Rated burden VA

7. a) Rated primary/secondary voltage KV/volt

b) Transformation ratio

8. Rated voltage factor

9. Rated insulation level a) One minute wet p.f. withstand voltage b) 1.2/50 micr-second impulse withstand voltage

KV KVp

10. Accuracy class

11. Maximum temperature rise after continuous full load operation a) Oil by thermometer b) Winding by resistance

Degree C Degree C

12. Porcelain housing a) Name of manufacture b) Governing specification c) Voltage class d) Creepage distance e) Weight

KV mm Kg

13. Overall dimensions Height Length Width

mm mm mm

14. Total weight of potential transformer with oil Kg

15. Whether the PT is of sealed construction with nitrogen at top or not Yes/No.

16. Pressure release device provided or not Yes/No

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APPENDIX-I

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APPENDIX-II

General Arrangement Drawing of Traction Substation for 2 x 25 kV AT Feeding system

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APPENDIX-III

Constitution of Shunt capacitor

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APPENDIX- IV

Schematic Diagram of Shunt capacitor Bank

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APPENDIX-V

Principle of AT feeding System

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APPENDIX-VI

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APPENDIX-VII TO

SPECIFICATION NO.: TI/SPC/PSI/2X 25/FC&SR/0100(…/10) (Referred to Clause 14)

Formula: K = Present worth in Rupee

D = Annual cost of power losses

i = Rate of compound interest on unit basis @ 7% per annum.

n = Expected service life of capacitor bank in years.

PL = Power losses

T = Tariff i.e. cost of energy in Rupee per kwh.

The capitalized values for capacitor bank shall be computed as under:

K = D {(1 + i)n - 1} i (1 + i)n

Where, D per watt = 365 x 24 x T 1000 = 8.76 T thus K = 8.76 T x (1 + i)n - 1 i (1 + i)n Hence the capitalized value in Rupees for power losses = K x PL

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specification no.:- ti/spc/psi/2x25/fc&sr/0100(...

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