11 kv vcbs and readout

8/4/2019 11 Kv VCBs and Readout

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TECHNICAL SPECIFICATION

FOR

11 kV, 12 PANEL BOARD

VACUUM TYPE SWITCHGEAR


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TECHNICAL SPECIFICATION FOR 11 kV SWITCHGEAR PANELSVACUUM TYPE

1.0 SCOPE:

This specification covers the design, manufacture, assembly, testing atmanufacturer's works before despatch, supply and delivery F.O.R.

destination as per schedule of requirement (Annexure 'I') of VacuumType, 12 Panel 11 kV Switch boards having normal current rating of1250 Amps. with rupturing capacity of 350 MVA.

2.0 STANDARDS:2.1 The circuit breakers shall conform to the latest revisions with

amendments available at the time of testing of relevant standards,rules and codes, some of which are listed herein for ready reference.

Sr.No.

STANDARD TITLE

1 IEC-56 Specification for alternating current circuitbreakers

2 IS-5578 & 11333 Making and arrangement for switch gear bus-bar main connection and auxiliary wiring.

3 IS- 2147 Degree of protection provide for enclosures for low voltage switch gear.

4 IS- 13118 Specification for circuit breakers.

5 IS- 3427 Disconnectors of circuit breaker & their interlocking .

6 IS-2099 High voltage porcelain bushings.

2.2 Equipment meeting with the requirement of any other authoritative standards,which ensure equal or better quality than the standard mentionedabove shall also be acceptable. if the equipment offered by thebidders conforms to any other standards , salient points of differencebetween the standards adopted and the specific standards shall beclearly brought out in relevant schedule . Four copies of suchstandards with authentic English Translations shall be furnishedalongwith the offer.

3.0 CLIMATIC CONDITIONS :

The equipment is required to operate satisfactorily under the followingsite conditions :

3.1 Max. temperature 500C3.2 Min. Temperature -2.50C3.3 Max. relative humidity 100%3.4 Min. relative humidity 26%3.5 Average number of rainy days per Nearly 120 days

annum.3.6 Average annual rainfall 900mm3.7 Average number of dust storm days 35

per annum.


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3.8 Isoceraunic level 453.9 Max. wind pressure 195 kg/Sq.mt.3.10 Altitude above mean sea level Less than 1000

mts.4.0 TYPE & RATING:

The panels 11 kV switchgear panels shall comprise of 11 kV Vacuum Typecircuit breakers, instrument panels and instrument transformers etc. suitablefor indoor use. The equipment shall be totally enclosed in a metal cladcubicle, dust and vermin proof with necessary isolation arrangement. Eachpanel shall be easily extensible on either side and should be complete withnecessary internal copper connections, small wiring, L.T. fuses andsupporting frame work with bolts to secure it to the floor. The Circuit Breakersshould be draw out type in horizontal position.

Principal parameters

The breakers shall have the following ratings :4.1 Type Vacuum

4.2 No of poles 3

4.3 Nominal system voltage 11 kV

4.4 Highest system voltage 12 kV

4.5 Rated frequency 50 +/- 1.5 Hz

4.6 Rated continuous current 1250 Amp for incoming & 400 Amp rating at an ambient for outgoing feeders.

temp. as specified inIS : 13118-1991(Latest edition)

4.7 Symmetrical breaking 350 MVAcapacity

4.8 Impulse withstand test 75 kV (Peak)voltage

4.9 One minute power 28 kV (rms)frequency withstandtest voltage

4.10 Short time current Not less than 18.4 kA currentrating corresponding to 350 MVA for 1 sec.

4.11 System neutral Solidly earthed.


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5.0 GENERAL DESIGN OF SWITCHGEAR PANELS :

5.1 OPERATING MECHANISM :The vacuum type circuit breaker shall be draw out type & trip free. TheVCBs shall be suitable for operation from 220 V DC auxiliary supply.The operating mechanism shall be motor operated spring chargedtype. There shall be provision(s) for manual charging of closing spring

and emergency hand trip. The motor used for the purpose will besuitable for 240 V AC as well as for 220 V DC . The operatingmechanism shall work satisfactorily at 85 % - 110 % of rated supplyvoltage. The VCB shall have 2 normally open & 2 normally-closedauxiliary contacts over & above the ones required for various control &supervision circuits.

5.2 INSTRUMENT PANELS :

Each unit shall have its own instrument panel provided at the top &complete with small wiring connections from relays, instrument

transformers, metering instruments, indicating instruments, selectorswitches & circuit breaker control switch.

All wiring shall be carried out by using stranded single annealed copperconductor insulated with poly vinyl chloride insulation suitable for 650 Vservice and in accordance with IS:732-1963. CT/PT circuit shall usewire of not less than 4.0 mm2 cross-sectional area whereascontrol/alarm/supervision circuit shall use wire of not less than 2.5 mm2

cross-sectional area. All wires will be continuous from one terminal tothe other and, also will have no Tee-junction enroute. The connectionsshall be securely made with the help of connecting lugs duly crimpedon to the copper conductor.

The meters and relays shall be mounted in a convenient position so asto be readily accessible for inspection or repair. The terminal boardprovided in the instrument panel of VCBs will be made of mouldeddielectric having brass studs, washers, holding nuts & locking nuts. Allholding nuts shall be secured by locking nuts. The connection studsshall project 6 mm from the lock nut surface. NO OTHER TYPE OFTERMINAL BOARD IS ACCEPTABLE.

The panels shall have a degree of protection of IP-4x. The leads frommetering CTs shall be directly terminated at TTB & there from at theKWH meter with a provision to seal TTB and KWH meter. The said CTleads will be concealed to prevent their tempering enroute. Similarly PTleads from secondary box of the PT to TTB & there from to energymeter including inter panel PT leads will also be concealed to preventtheir tempering. The mode & extent of concealing the metering leadsof CTs & PTs to prevent their tempering (by unscrupulous operatingpersonnel) will be discussed & mutually agreed upon with thesuccessful bidder(s). TTB used on the instrument panel should besuitable for front connections.


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Earthing of current free metallic parts or metallic bodies of therelays/switches mounted on the instrument panel and metal enclosedswitchgear shall be done by a suitably sized copper conductor. Earthbus made of 25x3 mm bare copper flat will be extended through entirelength of 11 kV switch-board with suitable provision to connect it to thesub-station earth at the extremities. The earthing arrangement willmeet with the requirements laid down in IS : 3427 read with its latest

amendment.

5.3 VACUUM INTERRUPTER :The Vacuum interrupter of 12 kV minimum 25 kA short time currentrating, 2000 Amp. normal current rating capable of withstandingminimum 100 full short circuit operations as per test duty 1 to 5 of IEC-56. Vacuum Interrupters for incomers as well as outgoing shall be ofsame type. These vacuum interrupters shall bear warranty for 5 yearsof free replacement from the date of commissioning and shall be ofapproved make only.

5.4 INSTRUMENT TRANSFORMER :The secondary voltage & current rating of the instrument transformersshall match with the metering or protective equipment. The CTs shallhave ratio & accuracy class as mentioned in the schedule ofrequirement. The CTs shall be wound/ring type in accordance with theirratings. The terminal boards associated with differential CTs, REF CTs& over current / earth fault protection CTs will be of disconnecting typehaving short circuiting facility & thus facilitate secondary testing ofconcerned protective relay without disturbing the associated smallwiring. Inter- changeability of housing of CTs from one panel to anothermust be ensured.

A resin cast potential transformer of ratio (11000/3)/(110/3) voltshaving 100 VA output per phase with accuracy class 1.0 as perISS : 3156 (part-II)-1965 shall be provided on the incoming side ofeach panel set and shall be star/star connected.

The neutral point of star connected secondary windings of instrumenttransformers shall be earthed to the main earth bus referred to in theconcluding paragraph of clause 5.2. Multiple earthing of any instrumenttransformers shall be avoided.

5.5 BUS - BARS :

All the panels shall be provided with one set of 3 phase 1250 Amps.heat shrunk PVC sleeves insulated Main electrolytic copper bus barsfor all switchboards and shall be connected in a separate moisture andvermin proof sheet metal chamber. The cross sectional area of busbar should however not be less than 1200 mm2 per phase. Thebus-bars connections & insulator supports shall be mechanically strung& rigidly supported so as to withstand the stresses generated by

vibrations, variations in temperature and due to severe short circuits.


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The bus bars shall be heat shrunk PVC sleeves insulated type andsupported on insulators at short intervals keeping adequate clearanceas per IE rules between bus bars and earth. However the minimumclearance between phases and phase to earth should not be less than95mm. The bus bar chamber shall be provided with inspection coverswith gaskets & bus bar shutters. Provision shall be made for future

extension of bus bar & switch board.

5.6 LIMIT OF TEMPERATURE RISE :

The temperature rise of the current carrying parts shall not exceed thepermissible limits above the ambient temperature as per relevantstandards (latest edition). However, the reference maximum ambienttemperature may be taken as 450C.

5.7 BUSHING INSULATORS:These shall comply with the latest issue of IS : 2099 in all respects.

5.8 DISCONNECTORS OF CIRCUIT BREAKER & THEIR INTERLOCKS

All disconnectors (isolators) of the 11 kV VCBs & interlocks betweendifferent pieces of apparatus provided for reasons of safety & forconvenience of operation of switchgear shall meet with the requirementof IS : 3427-1969 read with its latest amendment. Efficient mechanicalinterlocking shall be provided to meet the following conditionsi) It shall be possible to insert/withdraw the breaker only after

circuit breaker has been opened.ii) It shall be possible to insert/withdraw the breaker only when it is

fully open position as well as it is in Isolated/test position.iii) It shall not be possible to remove the breaker until the moveable

plug unit having secondary connections has been withdrawn.iv) It shall not be possible to replace in position moveable plug unit

unless the circuit breaker has been racked in.v) Provision of shutters or locks shall be made to prevent access to

bus bar chambers and receptacles when the circuit breaker iswithdrawn.

vi) Provision shall be made for locking the circuit breaker closingmechanism in open position.

5.9 CABLE BOXES:

Each 11 kV incoming VCB shall be provided with cable terminationarrangement suitable for receiving 2 sets of cable each comprising 3nos 630 mm2, 11 kV single core XLPE, outer PVC sheathed cables.However cable boxes complete with jointing kits & sealing materialsuitable for receiving 1 set of cable each comprising 3 nos 630 mm2, 11kV single core XLPE, outer PVC sheathed cables shall be supplied foreach incomer. The 11 kV capacitor controlling VCB shall be providedwith cable boxes suitable to receive 2 sets of 3 core, 11 kV XLPE PVC

Sheathed cables of size upto 185 mm2

(panel with CT ratio 300-150-


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75/5 A). The 11 kV station transformer VCB shall be provided withcable boxes suitable to receive 3 core, 11 kV, XLPE cables of size upto50 mm2 (panel with CT ratio 60-30/5 A). Each cable box shall havevertical entry from below. These cable boxes shall be complete in allrespects including cable glands of requisite size. The cable boxesshould only be either heat shrinkable or push on type. The cable boxesfor outgoing panels are not in the scope of this specifications.

5.9A Earthing TruckOne no. earthing trolley should be provided for each incomer panel.Earthing trolley must be full fault make type device which is capable ofmaking fault at 46.2 KA(peak) and carry 18.4 KA for one second. Theearthing truck for incoming panel must be so designed that it isimpossible to earth a live circuit.However manufacturers offering this astandard inbuilt feature of Breaker Trolley is also acceptable

5.10 SUPERVISI ON SCHEME :5.10.1 Instrument panels on each of the 11 kV VCB covered by this

specification shall be provided with the following indicatinglamps/relay:-

Circuit breaker òpen' GreenCircuit breaker `close' RedAuto trip WhiteCircuit breaker spring charged BlueFor monitoring of trip circuit both in pre-close and post- close positionof the circuit breaker, 1 no. automatic trip circuit supervision relay willbe provided on each of the 11 kV (incoming) instrument panel. In caseof trip circuit becoming faulty, the operation of this relay shall beaccompanied by visual and audio annunciation in accordance withclause 5.10.1 of the specification.

However, the trip circuit of each of the 11 kV outgoing / capacitor / Stn.VCB will be monitored òn demand' with the help of an indicating lamp& a push button both when the VCB is òpen & closed'. The lamp willbe àmber' coloured.

Circuit breaker `close' & òpen' lamps will be wired so as to be on 240V AC under `normal' condition. These lamps will be switched over to

220 V DC automatically in the event of failure of 240 V AC supply.Each of 11 kV (incoming) instrument panel will be equipped with asuitable relay for the purpose.

5.11 ALARM SCHEME :

5.11.1 NON TRIP ALARM SCHEME :

Each of 11 kV (incoming) panel will be provided with a non-trip alarmscheme comprising suitable auxiliary relay (rated for 220 V DC), acceptpush button, reset push button & a buzzer. It will cater to non-trip


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condition such as trip circuit faulty & PT secondary fuses blow `off'. Thenon-trip alarm scheme will meet with the following requirements:-

i) The closing of an initiating contact shall actuate a buzzer andwill be accompanied by a flag indication on the concernedauxiliary relay.

ii) The closing of an initiating contact shall glow a lamp which willnot reset until the fault has cleared.

iii) It shall be possible to silence the buzzer by pressing `accept'push button. If after cancelling the alarm but before resetting thevisual signal, the same fault persists the buzzer shall besuppressed.

iv) If after canceling the alarm but before resetting visual signalsome other fault takes place, the alarm accompanied by flagindication on appropriate auxiliary relay shall take place.

v) If after canceling the alarm and after resetting the visual signal,the same fault appears or some other fault take place, thealarm, flag indication and non-trip lamp indication shall reappearas usual.

vi) The non-trip alarm acceptance shall be by means of a pushbutton and resetting of visual signal may also preferably be donethrough a push button.

vii) Means shall be provided for test checking the lamp and alarmcircuit at frequent intervals.

viii) The equipment shall be suitable for 220 Volts DC operation.

5.11.2. TRIP ALARM SCHEME :

Trip commands due to operation of protective relay on any of 11 kVVCB constituting the switchboard will trip the concerned VCB. Itsauxiliary contact will actuate a bell (provided in each of the 11 kVincoming VCB) & will be cancelled by the associated circuit breaker

control handle. Auto trip lamp will glow on the concerned 11 kV VCB &there will be flag indication on the concerned protective relay.

5.12 PT FUSE FAIL ALARM SCHEME :

Each of the 11 kV (incoming) instrument panel is to be provided with arelay to monitor the fuses on the secondary side of 11 kV metering PT.The failure of any of secondary fuse on the 11 kV PT will beaccompanied by visual & audio indication in accordance with clause5.10.1 of the specification. None of the 11 kV outgoing/capacitor/Stn.VCB will be provided with fuses & inter-circuit PT leads may run from

one bus wire board to the other.


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5.13. METERING SCHEME :5.13.1 Each of the 11 kV VCB will be provided with a suitably sealed ammeter

(additional dials, if any, required to cover all the taps of the CTs shallbe included at the time of bidding) with a selector switch facilitatingmeasurement of phase currents as well as unbalance current. The coilof ammeter shall be rated for 5 Amp. The instrument shall be of moving

iron spring controlled type of industrial grade `A' classification havingaccuracy class 1.0 & shall conform to IS:1248(1968).

5.13.2 Each of the 11 kV (incoming) VCB will be provided with a suitablysealed voltmeter with a selector switch. The selector switch shallfacilitate the measurement of phase to phase & phase to neutralvoltage of all the three phases one by one. The coil of the voltmetershall be rated for 110 V (phase to phase). The instrument shall be ofmoving iron spring controlled type of industrial grade `A' classificationwith accuracy class 1.0 & shall conform to IS:1248(1968).

5.13.3 Each of the 11 kV VCB except the 11 kV capacitor VCB will beequipped with a three-phase four-wire Electronic KWH meter. The

KWH meter shall be rated for 5 A CT secondary and 110 V/3 (phaseto neutral) available from 11 kV PT mounted on each of the incomingVCB. The instrument shall be iron-cored dynamometer type havingaccuracy class 1.0.

5.13.4 Each of the 11 kV (incoming) VCB will be provided with a power factormeter. The PF meter having a range of 0.5Lag - one - 0.5lead shall beof 2 element type suitable for use on three phase three wireunbalanced system. It shall be rated for 5 A CT secondary & 110 V(phase to phase) available from 11 kV PT mounted on each of the 11kV incoming VCB. The instrument shall be iron-cored dynamometertype having accuracy class 1.0.

N.B. Routine test certificates of all the indicating & integrating instrumentswill be submitted alongwith the routine test certificates of 11 kVswitchgear.

5.14 CONTROL SCHEME :

5.14.1 The instrument panel of each of the 11 kV VCB will be equipped with acircuit breaker control handle of pistol grip type with spring return toneutral position and having bell alarm cancellation contacts. Thecontrol handle shall be so designed that after being operated to `close'a VCB the operation can not be repeated until the control handle hasbeen turned to `trip' position making it impossible to perform twoclosing operation consecutively.

5.14 .2 The rating of the control handle shall be suitable for the duty imposedby the closing and opening mechanism of VCB. The moving and fixedcontacts shall be of such a shape & material to ensure good contact


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and long life under service operating duty. All contacts shall be readilyrenewable.

5.14.3 The number of contacts in the control handle will be decided by thebidder keeping in view the requirements of this specification. Two pairsof contacts shall be kept spare. The total number of contacts proposedto be provided shall be stated in the bid.

5.14.4 Safety against inadvertent operation due to light touch on the controlhandle shall be ensured.

5.15 PROTECTION SCHEME :

5.15.1 FOR INCOMING PANELS :

Each incoming instrument panel shall be provided with a single polerestricted earth fault relay suitable for 5 A CT (Secondary) with asetting range of 10 % to 40 % of 5 Amp.( Strictly in steps of 5%). In

case, the bidder offers voltage-operated REF relay, the same shall betechnically justified with aid of sample calculations which will also forma part of the instruction manual for the said relay. The relay shall behoused in draw out flush mounting case. The back up protection shallbe in the form of a combined over current and earth fault relay(two overcurrent and one earth fault). This shall be triple pole having InverseDefinite Minimum Time (IDMT) characteristics with a 3/10 time currentcurve i.e. the relay operating time shall be 3 second at 10 times theplug setting at TMS 1. The outer element of the relay shall bearranged for over current protection and shall have a setting range of50-200 % of 5 A (The relay for station transformer shall have a settingrange of 20-80 % of 5 A) and adjustable in suitable equal steps bymeans of a plug board. The central element shall be used for earthfault protection with a setting range of 20-80 % of 5 A adjustable insuitable equal steps by means of a plug board (for station transformerpanels, the setting range shall be 10-40% of 5 A ) Each of the threeelements shall be fitted with shunt reinforcing unit with hand resetoperation indicator.

5.15.2 FOR OUTGOING FEEDERS PANELS :

Each outgoing feeder panel shall be provided with a triple pole IDMTLtype combined over current and earth fault relay (two over current andone earth fault element) conforming to the technical specification statedin the clause : 5.14.1 above and one set of triple pole instantaneousrelay (high set element) in the form of two over current and one earthfault element.

The outer element of the relay shall be arranged for over currentprotection and shall have a setting range of 500-2000 % of 5 A (Therelay for station transformer shall have a setting range of 200-800 % of5 A) and adjustable in suitable steps.


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The central element shall be used for earth fault protection with asetting range of 200-800 % of 5 A (The relay for station transformershall have setting range of 100-400 % of 5 A) adjustable in suitablesteps.

The relay shall have low transient over reach with a high pick-up/ dropof ratio. The relay will be connected in series with the triple pole

combined over-current and earth fault relay referred to above and shallbe so wired so as to take this (instantaneous) out, if so desired by thepurchaser at any time during operation of the equipment.

5.15.3 FOR CAPACITOR PANEL:Each capacitor panel shall be provided with the following relays forprotection of capacitor banks :-

i) Triple pole non-directional IDMTL type combined over current &earth fault relay (two over current & one earth fault element)conforming to the technical specification stated in clause 5.14.1

above.ii) 1 no. inverse time over voltage relay with setting range 100 % to

130 % of 110 V available from 11 kV PT mounted in the 11 kV(incoming) VCB alongwith auxiliary transformers(for externalmounting) of ratio 110/103.5 to 116.5 V ( in steps of one volt) tobe used for compensating the error of over voltage relay.

iii) 1 no. inverse time under voltage relay with setting range of 50 %to 90 % of 110 V (phase to phase connections).

iv) 1 no. neutral displacement rely with settings 5.4, 7.5, 12.5 & 20volts and to be fed from open delta winding of three phase(11000//3/(110//3) Volts. Residual voltage transformer (Residualvoltage transformer is not a part of this specification). Thebidders offering relays with different settings than above shalltechnically justify their offer.

v) 5 minute timer to ensure that the capacitor bank is fullydischarged once it has been switched "OFF" before it can beswitched "ON" again.

N.B. All protective relays covered by the specification shall be ofelectromechanical, draw out type mounted on the front of eachinstrument panel in a flush pattern case. The relay shall conform to IS :3231(latest edition) and will be suitable for 220 V DC auxiliary supply.The relay cover & case shall be dust proof, water proof & vermin proof.Operating indicators shall be provided on all protective relays/ on theirimmediate auxiliary units to indicate the type of fault &phase / phases involved. It shall be possible to reset the operationindication without opening the relay case. The routine test certificatesof all protective & auxiliary relays will be submitted alongwith routinetest certificates of 11 kV switchgear covered by the specification.


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5.16 D.C. FAIL ALARM SCHEME :

A suitable relay for monitoring the DC supply to the 11 kV switchboardshall be mounted on each of the 11 kV incoming instrument panel. Theoperation of DC fail scheme shall be accompanied by visual (indicatinglamp on the instrument panel) & audio (ringing of hooter) annunciation.

It shall be possible to silence the hooter by pressing the `accept' pushbutton while the lamp shall continue to glow till the fault has beenattended to & DC supply restored. A DC fail `Test' push button may beprovided to test the lamp circuit of the scheme.

6.0 TEST

All routine tests shall be carried out in accordance with IS : 13118-1991(latest edition thereof).

6.1 TYPE TESTS

The equipment offered should be type tested. Type test report shouldnot be more than seven years old, reckoned from the date of bidopening, in respect of the following tests, carried out in accordancewith ISS-13118/IEC-56, from Govt./ Govt. approved test house, shallbe submitted along with bid:

i) Impulse with-stand voltage tests.

ii) Power frequency voltage dry & wet tests on main circuits.

iii) Short circuit with stand capability tests.

iv) Mechanical endurance tests.

v) Temperature rise test.

However Mechanical endurance tests and Temperature rise testconducted at Firms works in the presence of representative of any ofthe SEBs/State Power Utilities shall also be acceptable.

The remaining type test report as per clause 6.0 of ISS-13118/IEC-56shall be submitted by the successful bidder with in three month fromthe date of placement of Purchase Order. These type test reports will

also be from Govt./ Govt. approved test house & shall not be more thanseven years old reckoned from the date of placement of order.

Voltage transformers & current transformers shall comply with the typetests as stipulated in the latest version of IS : 3156 & IS: 2705respectively. The reports of all type tests conducted shall be supplied.The 11 kV VCB & associated CTs & PTs shall be subjected to routinetests as specified in the latest version of the relevant ISS in thepresence of purchaser's representative, if so desired by the purchaser.The routine test certificates of bought out components such as relays,

switches, indicating instruments & KWH Meter will also be presented to


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HVPNL's inspecting officer who will forward them to the purchaseralongwith his inspection report for the main equipment. All test reportsshould be got approved from the purchaser before despatch ofequipment.

7.0 DRAWINGS :In addition to any other drawing which the tenderer may like to furnish

to explain the merits of his proposal, following drawings shall besubmitted with the tender in quadruplicate :

i Principal dimensional details of 11 kV Switchgear.

ii General arrangement of 12/14 Panel 11kV switchboardincluding its foundation details.

iii Schematic drawings of control, metering & protection circuits inrespect of 11kV incoming VCB, 11kV outgoing VCB includingstation transformer VCB & 11 kV capacitor VCB alongwith

detailed write-up.

iv Drawing showing height of 11 kV bus bars & arrangement of busbars

v Vacuum interrupter drawing.

Four copies of the descriptive literature in respect of 11 kV switchgear,relays, KWH meters, voltmeters, ammeters, selector switches etc.proposed to be used shall also be supplied.

The successful bidder shall submit within four weeks the above drawingsin quadruplicate on A-3 size paper to the C.E./Design & Procurement,Sub-Station Design Directorate, HVPNL, Power Colony, Panchkula forapproval. The purchaser shall communicate his comments/approval on/tothe drawings to the successful bidder within a period of four weeks. Thesupplier shall, if necessary, modify the drawings & resubmit four copies ofthe modified drawings for purchaser's approval within two weeks from thedate of receipt ofpurchaser's comments. The modified drawings will be approved within 15days of their receipt by the purchaser. After receipt of purchaser'sapproval to drawings, a set of reproducibles of approved drawings & five

sets of all the approved drawings and operating manuals containing,erection, operation & maintenance instructions per 11 kV switchboard shallbe supplied to CE/D&P, S/Stn. Design Dte., HVPNL, Power Colony,Panchkula for use by various agencies of the purchaser. However, one setof drawings and operating manual will be despatched alongwith each 11kV switch board. The 11 kV switchgear will not be fabricated withoutgetting the drawings approved from the purchaser.

In order to ensure timely receipt of all the drawings, literature &reproducibles etc., the purchase section of D&P organisation will issuedespatch instruction for despatch of 11 kV switchgear.


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8.0 SPECIAL TOOLS :

The tenderer shall separately quote for a set of special tools, if sorequired, for erection and maintenance of the switchgear panels.

9.0 DEVIATION FROM SPECIFICATION :

Should the tenderer wish to deviate from the provisions of the specificationeither on account of manufacturing practice, or any other reasons, he shalldraw attention to the proposed point of deviation in the tender and submitsuch full information drawing and specification so that merits of hisproposal may be fully understood. The specification shall be held bindingunless the deviation have been fully recorded as required above.

10.0 TRAINING FACILITIES :VOID

11.0 GUARANTEED AND OTHER TECHNICAL PARTICULARS :

These particulars shall be furnished strictly as per Annexure-A. Anydeviation from this specification shall be clearly brought outseparately.

12.0 STANDARD MAKE(S) OF RELAYS/OTHER FITMENTS :

The makes of relays/switches/other fitmens may be restricted to asdepicted in Annexure B.


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ANNEXURE -'I'SCHEDULE OF REQUIREMENT

1. VACUUM TYPE 14 PANELS, 11 kV SWITCH BOARDS AND EACH

SWITCH BOARD COMPRISING OF THE FOLLOWING :-1.01. 1 NO. INCOMING PANEL EQUIPPED AS BELOW :

-1 No. Triple pole 350 MVA, 11 kV 1250 A draw out type vacuum circuit

breaker fitted with arc control device, interlocks, auxiliary switchesisolating contacts, emergency hand trip device, mechanical `ON' & `Off'indicator and motor operated spring charged mechanism.

-1 Set Bus bars 3 phase 1250 A. Cable termination arrangement located atthe rear of the unit for receiving 2 set of power cables each comprising3 no. single core 630 mm2 11 kV XLPE PVC sheathed cables &complete in all respect. Cable boxes with jointing kits etc. as per clause5.9 of the specification.

-3 No. CTs of ratio 900-450/0.577-5 A with first core for differential protectionhaving a minimum knee point voltage equal to 40 RCT (neglecting leadresistance) and the 2nd core for REF protection having a minimumknee point voltage of 92(RCT)V on 900 A tap where RCT secondarywinding resistance. These CTs shall conform to accuracy class PS ofISS:2705 (Part-IV) and shall have Magnetising current as low aspossible but in no case exceeding the value corresponding to class 5 Pof IS:2705 (Part-III).

-3 No. CTs of 900-450/5 A of 15 VA output and 5P10 accuracy for overcurrent and earth fault protection

-3 No. CTs of 900-450/5 A of 15 VA output, accuracy class 1 & ISF less than 5for metering instrument.

-1 No. 3 phase star/star connected resin cast voltage transformer of ratio11000/%3 /110/%3 volts having 100 VA output for phase withaccuracy class 1.0 as per IS: 3156 (Part-II)1965 complete with HT & LTfuses, isolating plugs and sockets for HT & LT copper connectors,current limiting resistances.

-1 set Vermin and dust proof fitments.

-1 NO. INSTRUMENT PANEL MOUNTED ON TOP AND EQUIPPED ASBELOW:

-1 No. Ammeter with selector switch as per clause : 5.13.1 of thespecification.


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-1 No. Voltmeter with selector switch as per clause : 5.13.2 of thespecification.

-1 No. KWH meter with TTB as per clause : 5.13.3 & 5.2 of the specification.

-1 No. PF meter with TTB as per clause : 5.13.4 of the specification.

-1 Set Triple pole combined over current and earth fault IDMTL relay as perclause : 5.15.1 of the specification.

-1 No. Single pole restricted E/F relay as per clause : 5.15.1 of thespecification. This relay will have one of its main contacts used forinter-tripping the H.V. transformer controlling circuit breaker.

-1 No. Tripping relay with hand reset contacts suitable for 220 V DC auxiliarysupply.

-4 No. Indicating lamps with fittings to indicate breaker `open', `close', `autotrip' & spring charged as per clause 5.10 of the specification.

-1 No. Automatic trip circuit supervision scheme as per clause 5.10 of thespecification.

-1 No. PT fuse alarm scheme as per clause 5.12 of the specification.

-1 No. DC fail alarm scheme as per clause 5.16 of the specification.

-1 No. Circuit breaker control handle as per clause 5.14 of the specification.

-1 No. Alarm equipment for non-trip & trip fault annunciation as per clause5.11.1 & 5.11.2 of the specification.

-1 No. Cubicle illumination lamp with door operated ON/OFF switch.

-1 No. 15 A power socket with switch.

-1 No. Anti-condensation tubular space heater suitable for connection to 240V AC supply with a thermostat & a miniature circuit breaker.

1.02 6 N0. OUTGOING FEEDER PANELS EACH COMPRISING OF :

-1 No. Triple pole 400 A, 350 MVA 11 kV circuit breaker fitted with Arc controldevices, interlock arrangement, auxiliary switches, isolating contacts,emergency hand trip device, mechanical ON & OFF indicator & motoroperated spring charged mechanism operate at 220 V DC.

-1 Set Bus bars 3 phase 1250 A.


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-3 No. CTs of ratio 300-150/5-5 A with first core of 15 VA output & 5P10accuracy for O/C & E/F protection & second core 15 VA output &accuracy class 1.0 for metering.

-1 No. Anti-condensation tubular space heater for connection to 240 V AC

supply with a thermostat & a miniature circuit breaker.-1 Set Vermin proof & dust proof fitments.-1 No. Instrument panel mounted on top & equipped as below :--1 No. Ammeter with selector switch as per clause : 5.13.1 of specification.

-1 No. KWH meter with TTB as per clause : 5.13.3 & 5.2 of the specification.

-1 set Triple pole combined 2 O/C & 1 E/F IDMTL relay supplemented withtriple pole instantaneous relay (high set element) in the form of 2 O/C &1 E/F as per clause : 5.14.2 of the specification.

-1 No. Tripping relay with hand reset contacts suitable for 220 V DC auxiliarysupply.

-4 No. Indicating lamps with fittings to indicate breaker `open', `close',`auto-trip' & 'spring charged' as per clause 5.10 of the specification.

-1 No. Indicating lamp with fittings & push button switch to indicate trip circuithealthy in pre-close & post-close conditions as per clause : 5.10 of thespecification.

-1 No. Circuit breaker control handle as per clause : 5.14 of the specification.

-1 No. Cubicle illumination lamp with door operated ON/OFF switch.

-1 No. 15 A power socket with switch.

-1 No. Anti-condensation tubular heater suitable for connection to 240 V ACsupply with a thermostat & a miniature circuit breaker.

1.03 2 NOS. OUTGOING FEEDER PANELS:-

Similar to item 1.02 but with following cable box/CTs :-

-3 No. CTs of ratio 200-100/5/5 A with first core of 15 VA output & class 5P10accuracy for O/C & E/F protection & second core of 15 VA output &accuracy class 1.0 for metering.


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1.04 1 NO. PANEL FOR CAPACITOR BANK :

The capacitor controlling breaker should be suitable to meet all conditionsrequired for capacitor operation & should be suitable for controllingcapacitive current upto 400 A at 11 kV which is equivalent to 7.5 MVARapprox. & equipped similar to item No. 1.02 except KWH meter but with the

following changes/additions :

-2 No. Trifurcating main cable box for receiving 3 core XLPE, PVC sheathed cableupto 185 mm2 size and complete with cable glands and jointing kits etc. asper clause : 5.9 of the specification.

-3 No. CTs of ratio 300-150-75/5 A output & 5P10 accuracy for over current &earth fault protection.

- Protection scheme including closing circuit interlock timer shall be as perclause : 5.15.3 of the specification.

1.05 1 NO. STATION TRANSFORMER FEEDER PANEL :

Similar to item No. 1.02 but with the following cable box & CTs :-

-1 No. Trifurcating main cable box for receiving 3 core XLPE cable upto 50 mm2

size & complete in all respect as per clause : 5.9 of the specification.

-3 No. CTs of ratio 60-30/5-5 A with first core of 15 VA output & class 5P10accuracy for O/C & E/F protection & second core of 15 VA output &accuracy class 1.0 for metering.

1.06 1 No. INCOMING PANEL EQUIPPED EXACTLY IDENTICAL TO ITEM 1.01DETAILED ABOVE

NOTE : The two incoming panels at Sr. No. 1.01 & 1.06 shall be placed at thetwo extreme ends of the switch board. Provision shall be made to splitthe 14 panels boards into two parts each having an incoming panel atits end with complete non-trip alarm, trip alarm & protection schemes.


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ANNEXURE-'A'

SCHEDULE OF GUARANTEED AND OTHER TECHNICAL PARTICULARS

1. Maker's name & country of manufacturer.2. Type3. Nominal system voltage4. Highest system voltage

5. Frequency6. Normal current ratings

a) As ref. ambient temp.as per relevant standard.

b) At site conditions.

7. Symmetrical breaking capacity.

8. Asymmetrical breaking capacity

9. a) Symmetrical breaking currentb) Short time current rating for 1 sec.

10. Making capacity.

11. 1.2/50 Micro second impulse wave withstand test voltage.

12. One minute power frequency withstand test voltage.

13. No. of poles

14. No. of breaks in circuit per pole.

15. Length of break per phase.

16. Opening time

17. Making time

18. Arc duration

19. a) Type and material and main contactsb) Material & thickness of plating of contacts.

20. Type of arcing contacts and/or arc control device.21. a) Whether the circuit breaker is trip free ?

b) Whether it is with lock out preventing closing ?

22. Nominal voltage of closing mechanism.

23. Power required to close circuit breaker at nominal voltage.

24. Minimum clearance in aira) Between phases.b) Between the live parts and earth


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25. Minimum clearance in vacuuma) Between phasesb) Between live parts & earth

26. Total weight of complete breaker

27 Dimensions and mounting details

28. Standard to which conforms

29. Details of reference drawings attached.

B. INSTRUMENT TRANSFORMERS :

i) CURRENT TRANSFORMERS :

a) Name of manufacturer.

b) Rated primary current

c) Rated secondary current

d) Rated transformation ratio

e) V.A. oputput at rated current & accuracy

f) Class of accuracy.

g) Rated over current factor with time in seconds.

h) Type of CTs(whether wound or bar type)

i) One minute power frequency withstand test voltage.

j) 1.2/50 micro second impulse withstand voltage.

k) Standard to which conform.

ii) VOLTAGE TRANSFORMER :(i) Name of manufacturer.

(ii) Rated primary voltage

(iii) Rated secondary voltage

(iv) Rated burden

(v) Class of accuracy

(vi) Rated voltage factor and time

(vii) One minute power frequency withstand test voltage.

(viii) 1.2/50 micro second impulse withstand test voltage.

(ix) Standard to which conform.


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C. RELAYS :(i) Name of manufacturer.

(ii) Type & make

(iii) Setting range

(iv) Other details

(v) Standard to which conform

D. BUS BAR1. Material

2. Normal current rating

3. Nominal area per phase

4. Shape.

5. Type of insulation.

E. VACUUM INTERRUPTER BOTTLE1. Name of manufacturer.

2. Whether imported or indigenous.

3. Manufacturer's type, normal Amps. &rupturing capacity for vacuum bottlesused on incoming panel.

4. Manufacturer's type, normal Amp. &rupturing capacity for vacuum bottlesused on outgoing panel.

5. Manufacturer's type,. normal Amps.& rupturing capacity for vacuum bottlesused on capacitor control panel.

6. Degree of vacuum inside the vacuum interruptors.

7. Short time rating of vacuum bottles.

8. Number of full short circuit operation,as per test duty 1 to 5 of IEC-56 whichthe vacuum bottles offered can safely withstand.

9. Whether the vacuum bottles used onincoming and outgoing panels are sameor different.

10. Whether the operating mechanism isimported or indigenous.

(SIGNATURE OF SUPPLIER)


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ANNEXURE -'B'

STANDARD MAKE (S) OF RELAYS/FITMENTS

1. RELAYS -ALSTOM/EASUN REYROLLE/ABB

2. BREAKER CONTROL SWITCH -KAYCEE/ALSTOM/RECOM

3. AMMETER/VOLTMETER/SELECTOR -KAYCEE/RECOMSWITCH

4. AMMETER/VOLTMETER/POWER -AE/IMP/MECOFACTOR METER

5. WATT HOUR METER -SIMCO/AE/ABB/ENERCON/L&T/SECURE

6. PUSH BUTTONS -ALSTOM/KAYCEE/VAISHNO

7. INDICATING LAMPS WITH LENSES -ALSTOM/KAYCEE/VAISHNO

8. CABLE TERMINATION KITS -DENSON/M-SEAL/CAB SEAL

9. CABLE GLANDS -DENSON/M-SEAL/COMET

10. PANEL WIRING -ECKO/PHOENIX

11. HOOTER/BUZZER/BELL -ANCHOR/KAYCEE

11 kv vcbs and readout

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