csc-xx

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E:\WEBSITE_DATA_2012\Tech_Spec\27.12.12\CSC Approved Tech Spcn 33 KV C&R Panels With Group Control Of 2 T-Fs, R-III 17712.Doc of 20

Specification No. CSC-XX-R-III/DH/UH/P&D/2012-2013

TECHNICAL SPECIFICATION

FOR

33 kV CONTROL & RELAY PANEL

Issue Month: November, 2012 Common Specifications Committee

(CSC approval date 26.9.2012) UHVN & DHBVN

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TECHNICAL SPECIFICATION OF INDEPENDENT 33KV TRANSORMER AND FEEDER

CONTROL AND RELAY PANELS FOR 33KV SUB STATION & FOR GROUP CONTROL OF

2 Nos. OF 33/11 KV TRANSFORMERS

1. SCOPE:

The specification covers the design manufacture, testing before dispatch, supply &

delivery along with associated sundries to complete the job. A control and relay panel shall

include the following:

a) Protective and auxiliary relays required for the protection of transformers and lines.

b) Indicating instruments with necessary switches

c) Control switch for the remote control of 33 KV circuit breaker.

d) Supervision equipment

e) Mimic equipment

f) Alarm equipment

g) Terminals, wiring ferrules, fuses, links and sundries to complete the job.

2. STANDARDS:

All material and equipment shall comply in every respect with the requirements of the

latest edition of the relevant standards as specified here. Equipment meeting with any other

internationally recognised standards will be acceptable.

Protective relays IS: 3231

Indicating Instruments IS: 1248

Mimic colour shades IS: 1961

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3. CLIMATIC CONDITIONS:The equipment/material to be supplied against this specification shall be suitable

for satisfactory operation under the following climatic Conditions

i) Location At various locations in the stateof Haryana

ii) Max ambient temperature (deg.c) - 60

iii) Min ambient air temperature (deg. c) -5iv) Max average daily ambient temperature (deg. c) 40

v) Max. yearly weighed average ambienttemperature (deg. C)

32

vi) Max. altitude above mean sea level (Meters) 1000

vii) Minimum Relative Humidity (%age ) 26viii) Max. Relative Humidity (%age) 95ix) Avg. no of Rainy days/ year 120

x) Avg. annual rainfall 900mmxi) Maximum wind pressure 195 Kg./mm Sq.

The equipment shall be for use in moderately hot and humid tropical climate, conducive to rustand fungus growth.

4. SYSTEM PARTICULARS AND AUXILIARY SUPPLIES:

4.1 33KV voltage supply will be 3 phase, 50 Hz.

4.2 Wherever the neutral is provided on the power transformer, the same will be solidly

earthed.

4.3 A.C. supply at the 33KV sub-station for which the C&R panels against this

specification are required will be 415/240 Volts, 3 phase, 4wire, 50Hz+ 3% variation.

4.4 D.C. supply available at the sub stations for which the C&R panel against this

specification are required will be 24 Volts, 2 wire available from the sub-station battery.

The supply may have + 10% variation.

5. TEST SHEETS:

Guaranteed test sheets as per Annexure ‘A’ will be submitted by the tenderer alongwith

the tender. Relevant literature will be supplied for proper appreciation of the offered

equipment.

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6. SPARE PARTS:

The cost of the following items may be quoted separately so that the same bepurchased as spares, if considered necessary.

6.1 Triple pole IDMTL type over current relay with instantaneous attachments, non-

directional combined over current and earth fault relay, auxiliary relays (used in the

alarm scheme) semaphore relays used on the panel.

6.2 Control handle used on the panel for the remote control of circuit breaker.

6.3 Ammeter & Voltmeter used on the panel.

6.4 INDICATING LAMPS, BELL BUZZER:

At list of spare parts recommended for 5 years of normal operation shall be furnished

with the tender. Actual quantities to be ordered shall be determined by the purchaser.

7. DEPARTURE FROM SPECIFICATION:

Should the tenderer wishes to depart from the provision of this specification either on

account of manufacturing practice or for any other reason, he will draw special attention to the

proposed points of departure in his tender and submit such full information, drawing and

specifications as will enable the merit of his proposal to be appreciated.

In the event of supplier’s drawings, specifications and tables etc., disagreeing with this

specification during the execution of contract, this specification shall be held binding unless the

departures have been fully recorded and agreed upon by purchaser as required above.

8. DRAWING:In addition to any other drawings which the tenderer may like to enclose to explain the

merits of his proposal, the following drawings shall be enclosed with the tender in quadruplicate:

i) Major dimensional drawing of each of the three types of C & R panel.

ii) Feeder circuit protection scheme.

iii) Transformer circuit protection scheme in respect of both types of transformers C &R

panel.

Within 15 days after the date of issue of firm order together with other essential technical

particulars( by the purchaser), the supplier shall furnish 4 copies each of the

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dimensional drawings, schematic drawings and wiring drawings of C&R panels for

purchaser’s approval, enabling him to determine that the design proposed can be

satisfactorily fabricated. The purchaser shall have the right to require the supplier to

make any other change in the design, which may be necessary in his opinion to make

the equipment conform to the stated provisions of the specification without additional

cost to the purchaser. Approval by the purchaser of the supplier’s drawings shall not be

held to relieve the supplier of any part of the contract obligation to meet all the

requirements of this specification.

9. ILLUSTRATED AND PRINTED LITERATURE:

Two copies each of the descriptive and printed literature in respect of all instruments

switches and relays used on the offered panels shall be supplied alongwith the tender.

10. PLACE OF MANUFACTURE & INSPECTION:

The tenderer shall state in his tender the place(s) of manufacture, testing and inspection

of the various portions of the work included in the tender.

The purchaser or his duly authorized agency shall have access to the supplier’s works

at any time during working hours for the purpose of inspecting the manufacture of material,equipment etc., and the supplier shall provide the necessary facilities for inspection.

11. TESTS:

The following tests shall be carried out at the manufacturer’s works after complete

assemble of control and relay panel board and the test report of such tests supplied in

quadruplicate for approval of CGM/MM, DHBVN / UHBVN before despatch of equipment: -

i) Checking of wiring circuits and their continuity.ii) One minute applied voltage test for all equipment on panels and wiring.iii) Insulation resistance of complete wiring, circuit by circuit with all equipments

mounted on the panel.iv) Checking the operation of protective relays.

All instruments, auxiliary relays and protective relays used on the panels shall comply

with the latest edition of relevant Indian/Other internationally acceptable standards and routine

test certificates for the same supplied and got approved from the purchaser.

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Type test reports relating to all protective relays as per relevant standards shall be

submitted by the tenderers alongwith their tender for reference of the purchaser.

The type test reports should not be more than five years old reckoned from the date of

bid opening. The type tests should be got carried out from the Govt./Govt. approved NABL

accredited test house as per relevant ISS.

Immediately after finalisation of the programme of acceptance/routine testing, the

supplier shall give sufficient advance intimation (at least 15 days notice for Indians suppliers and

30 days notice for Foreign supplier) to the purchaser to enable him to depute his representative

for witnessing the tests.

12. FAKE INSPECTION CALL

The manufacturer shall be responsible to pay penalty of Rs 20,000/- for each

occasion at which the fake inspection call has been made or the material is rejected during

testing/inspection by the authorized agency/representative of the Nigam. This penalty would

be in addition to the expenses incurred by the Nigam in deputing the Inspecting Officer,

carrying out such inspection

13. INSTRUCTION BOOKLETS: Operating, testing, commissioning and maintenance instructions in English language

covering all the protective and auxiliary relays and instruments shall be put under a common

cover and six such sets shall be supplied free of cost at least one month before despatch of the

C&R panel.

13. REPRODUCIBLE DRAWINGS:

The supplier shall supply one set of full size reproducible of dimensional drawings,

schematic drawings and wiring diagrams of the three types of control and relay panels against

the contract either on tracing cloth or on synthetic paper enabling easy multiplication of prints as

and when required by the purchaser. The supplier will also supply six sets of drawings for each

type of C&R panels, each set consisting of dimensional schematic and wiring diagrams of the

panels.

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14. PACKING AND TRANSPORT:The supplier shall be responsible for suitable packing of all the material and marking on

the consignment so as to avoid any damage during the transport and storage and to ensure

correct despatch to the destination.

15. MARKING:The following particulars shall be marked distinctly and permanently on every relay

preferably in a position visible from the front.

(a) Manufacturer’s name or the make by which he may be identified.

(b) Manufacturer’s type reference.

(c) Rated current, rated voltage or both.

(d) Frequency.

(e) Particulars of auxiliary equipment.

(f) Setting indication.

(g) Manufacturer’s serial Number.

(h) Country of manufacture.

Relays must be marked with ISI certification mark.

Meters shall have markings as per ISS 1248-1983 or latest version thereof/equivalent

IEC.

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PART-II TECHNICAL PARTICULARS

1. GENERAL DESCRIPTION OF CONTROL & RELAY PANEL:

The control and relay panel shall consist of separate cubicle with side covers made of

sheet steel and complete with internal wiring, terminals, ferrules and illumination with door

operated ‘OFF’ and ‘ON’ switch. The cubicle shall be suitable for floor mounting with its bottom

open and shall be completely dust and vermin proof. The cubicle shall be of suitable height with

adequate depth and width so as to afford comfortable working area inside the panel for testing

staff. Each cubicle shall be fitted with flush mounted steel hinged door and lock at the back and

all the equipments (control, supervisory, metering and protective) will be mounted in front. The

supply shall include the channel base, suitable grouting bolts, nuts, locknuts, washers etc.

alongwith the panels.

The individual panels shall have provision for extension at both ends so as to form a

board as per the requirement.

2.

SUPERVISION SCHEME:

Each of the control and relay panel against the specification shall be fitted with the

following supervision lamps: -

Circuit breaker close: Red.

Circuit breaker open: Green.

Auto-trip: Amber.

Trip circuit healthy: White.

(Monitoring both when

Breaker is OFF/ON)

All lamps except circuit breaker close and circuit breaker open indicating lamps shall be

rated for 24 volt D.C. The lamps shall have low wattage consumption and shall provide a

comfortable viewing.

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Circuit breaker close and circuit breaker open indication lamps will be suitable for 220V

AC. Glass/plastic lens of appropriate colour shall be screwed into the front of the lamp

body.

An engraved label indicating the purpose of the lamp shall be provided with each lamp.

In the initial supply 20% of the lamps actually used on the switch board and 10% of lamp

lenses of various colours shall be supplied loose to serve as spares.

3. ALARM SCHEME:a) Alarm scheme for t rip alarm due to electr ical faul ts :

Trip commands due to operation of protective relays including Buchholz relay and

winding temperature trip contacts will actuate bell and will be cancelled by the circuit

breaker control handle. Auto trip lamp will glow on the panel and there will be flag

indication on the concerned protective relay/auxiliary relay of the panel.

b) Alarm scheme for non tr ip alarm: This scheme will conform to the following:i) The closing of an initiating contact shall actuate a buzzer and will be

accompanied by a flag indication on the concerned auxiliary relay.

ii) The closing of an initiating contact shall glow a lamp, which will not reset until the

fault has cleared.

iii) It shall be possible to silence the buzzer by pressing ‘accept’ push button,. If

after canceling the alarm but before resetting the visual signal, the same fault

persists the buzzer shall be suppressed.

iv) If after canceling the alarm but before resetting the visual signal some other fault

takes place then the alarm accompanied by the flag indication on the concerned

auxiliary relay shall take place.

v) If after canceling the alarm and after resetting the visual signal, the same fault

reappears or some other fault takes place, the alarm flag indication and non-trip

lamp indication shall reappear as usual.

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vi) The non-trip alarm acceptance shall be by means of a push button and resetting

of visual signal may also be done through a push button.

vii) Means shall be provided for test checking the alarm and lamp circuits.

viii) The equipment shall be suitable for 24 D.C. operation.

3.1 Four ways for the annunciation of non-trip alarm on transformer panels with the following

description shall be provided:

TRASFORMER PANELS:1) Buchholz alarm

2) Winding temperature alarm

3) Oil temperature alarm

4) OLTC oil surge relay & low oil alarm

3.2 Four ways for annunciation of trip & alarm on T/F panels with following description shall

be provided:

I ) Buchholz trip

2) Winding temperature trip

3) Oil temperature trip.

4) OLTC oil surge relay trip.

N.B.: 33 kV transformer panels meant for the group control of 2 Nos. 33/11 kV transformers

shall be provided with necessary auxiliary relays for independent annunciation of the non-trip

alarms (such as Buchhloz’s alarm, winding temperature & Oil temperature alarm, OLTC Oil

surge relay & Low Oil alarm etc)., trip (such as Buchhloz’s trip, winding temperature, Oil

temperature trip & OLTC Oil surge relay trip etc.) conditions of transformer.

4. MIMIC SCHEME:4.1 Suitably painted mimic diagram will be reproduced on the panels. Automatic semaphore

indication for indicating OPEN and CLOSE position of circuit breakers, isolators and

earth switches shall be suitably incorporated in the mimic diagram as per Sketch-

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I(enclosed). The operating coil of the semaphore relays shall be suitable for use on

24VD.C.

4.1 Following colour scheme shall be used for mimic representation on the panels against

this specification:

Voltage panel Colour Shade No. (according to ISS-1961)33KV Brilliant green 221

11KV Signal 537

5. METERING SCHEME:

Voltmeters & Ammeters on all the panels against the specification shall be of square,

flush mounting type. The line panels shall be mounted with both voltmeter & ammeter,

whereas the transformer panel shall have only the ammeter.

5.1 Voltmeter shall be accompanied by a suitable selector switch facilitating the

measurement of voltage between phase to phase and between phase to neutral. The

voltmeter coil shall be rated for 110 Volts between phase to phase obtainable from the

secondary of potential transformers. The instrument shall be of moving iron spring

controlled type grade ‘A’ classification with an accuracy class of 1 and shall conform to

IS: 1248- 1983, IS:2419-1963 (latest version there of) or relevant BIS, IEC or ASA

standard.

5.2.1 Suitably sealed ammeter to cover CTs ratio shown in sketch-I shall be accompanied by

a selector switch facilitating the measurement of phase currents as well as the

unbalanced current in the neutral. The ammeter coil shall be rated for 5 Amp. The

instrument shall be of moving iron spring controlled type of industrial grade ‘A’

classification with an accuracy class 1 and shall conform to IS: 1248-1983, IS: 2419-1963 (latest version thereof) or relevant BIS/ I.E.C or ASA standard

6. CONTROL SCHEME AND CONTROL SWITCHES:

It shall be possible to close the breaker from the control room. For this purpose controlswitches with built in key free locks having pistol grip type or handles of the spring return toneutral position type with alarm (cancellation) contacts shall be provided for operation of circuitbreakers.

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7. PROTECTION SCHEME:

7.1 TRANSFORMER PANELS:Triple pole over current relay IDMTL type with high set elements For Over Current

protection a triple pole inverse definite minimum time lag over Current relay with a setting range

of 50%-200% (of 5Amp Rating) and also fitted with high set elements of 500%-2000% of 5A for

instantaneous clearance of faults within the transformer(s) shall be provided on each of the

transformer control and relay panel.

For restricted earthfault protection to 33KV winding of the power transformer, an

instantaneous balanced earth fault relay shall be provided on each of the transformer C& R

panel. The relay shall have a setting range of 10%-40% of 5Amp. & shall be complete with 50Hz

circuit & stabilizing resistance.

Note: R.E.F. protection is not required for the transformer having capacity 5 MVA & below.

7.2 LINE PANEL: Triple pole combined over current and earth fault relay:-Triple pole combined over current and earth fault relay consisting of outer two over

current elements having setting range 50% to 200% of 5Amp having IDMTL characteristics and

inner earth fault element having setting range of 20-80% of 5Amp having IDMTL characteristic

shall be provided on each of the 33KV line panel.

7.3 TRANSFORMER DIFFERENTIAL PROTECTION (FOR CAPACITY 10 MVA &

ABOVE):

The relay shall

i. Be triple pole numerical type.

ii. Have 3 instantaneous high set differential units.

iii. Have second harmonic restraint or other inrush proof feature and be stable under

normal over fluxing condition.

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iv. Have fifth harmonic by pass filter or similar other arrangement to prevent mal-operation

of the relay under operating conditions.

v. Be suitable for rated current of 5A and include necessary ICTs for ratio & phase angle

correction.

vi. Have operating current setting sufficiently low (15% or less) so as to cover practically

the whole of the transformer against all types of faults.

vii. Have adjustable bias setting range of 20-50%. Have maximum operating time of 30milli

seconds at 5 items the rated current.

viii. Be provided with necessary terminal & links to measure current in restraining circuits &

in the operating circuits of all the phases under load without making any wiring changes.

ix. Display resolution of differential/pickup current should be 0.01A (10 MA).

8. SMALL WIRING:8.1 All the wiring shall be of switchboard type consisting of single tinned annealed copper

conductor insulated with polyvinyl chloride insulation suitable for 660 volts service and in

accordance with IS: 732-1963 (latest version thereof).

8.2 The wiring of the following circuits shall be not less than the size specified below:

CTs and PTs circuits: 2.5 mm sq

Control alarm, supervision circuits: 1.5 mm sq.

8.3 All wires will be continuous from one terminal to the other and also will have no tee-

junction enroute. At the terminal connections, washers shall be interposed between

terminals and holding nuts. All holding nuts shall be secured by locking nuts.

8.4 Bus wires shall be fully insulated and run separately. Fuses and links shall be provided

to enable all the circuits in a panel to be isolated from the bus wire. Wherever

practicable all circuits in which the voltage exceeds 125 volts shall be kept physically

separated form the remaining wiring. The function of each circuit shall be marked on the

associated terminal board.

8.5 All wiring diagrams for the control and relay panel shall be drawn as viewed from the

back of the cubicle and shall be in accordance with ISS: 375-1963 (latest version

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thereof). Multicore cable tails shall be so bound to its cable that each wire may be

traced without difficulty.

9 TERMINAL BOARDS:

9.1 Terminals block connectors built from cells of moulded dielectric and brass stud inserts

shall be provided for terminating the outgoing ends of the panel wiring and the

corresponding tail ends of Control Cables. Insulating barriers shall be provided between

adjacent connections. The height of barriers and spacing between terminals shall be

such as to give adequate protection while allowing easy access to terminals.

9.2 Terminal blocks shall be suitable for 660 Volts service and for connection with both

copper and aluminum wires.

10. CONTROL AND RELAY CUBICLES

i) The Control and Relay Cubicles shall be made of Sheet Steel of thickness not less than10 SWG (3.251 mm) for the base frame, door frame, front & Rear portions of Cubicle &not less than 14 SWG (2.032 mm) for doors, side, top & bottom portions, in place of sheet metal of 2 mm thickness.

ii) The main REF, Differential relays, Over Current & Earth Fault relays should only be of AREVA / ABB / SIEMENS / EASUN REYROLLE / JVS make and shall be of numerical

type. However, the Auxiliary relays may be of electromechanical type.iii) The C&R Panels should be of standard dimensions as under:-

Depth = 610 mm.

Height of switch Board above base frame = 2210 mm.

Height of base frame = 102 mm.

11. FERRULES, SPACE HEATERS AND SAFETY EARTHING:

11.1 Ferrules engraved with some number and letters as indicated in the connection andwiring diagram shall be provided on the terminal ends of all wires for easy identificationof circuits for inspection and maintenance.

11.2 Tubular space heaters suitable for connection to the single phase 230 Volts A.C. supplycomplete with switches shall be provided at the bottom of each control and relay panelto prevent condensation of moisture.

11.3 Earthing of current free metallic parts or metallic bodies of the equipment mounted onthe switchboard shall be done with copper conductor of suitable size.

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12. CHALLENGE CLAUSE

The material offered/received after the inspection by the authorized inspecting officer

may again be subjected to the test for losses or any other parameter from any Testing House/in-

house technique of the Nigam & the results if found deviating un-acceptable or not complying to

approved GTP's the bidder shall arrange to supply the replacement within thirty (30) days of

such detection at his cost including to & fro transportation. In addition to this penalty @10% of

cost of the inspected lot of material shall be imposed

13. WARRANTEE PERIOD

The supplier shall be responsible to replace, free of cost, with no transportation or

insurance cost to the Purchaser, up to destination, the whole or any part of the material which in

normal and proper use proves the defective in quality or workmanship, subject to the condition

that the defect is noticed within 18 months from the date of receipt of material in stores or 12

months from the date of commissioning whichever period may expire earlier. The consignee or

any other officer of Nigam actually using the material will give prompt notice of each such defect

to the supplier. The replacement shall be effected by the supplier within a reasonable time, but

not, in any case, exceeding 45 days. The supplier shall, also, arrange to remove the defectivewithin a reasonable period, but not exceeding 45 days from the date of issue of notice in respect

thereof, failing which, the purchaser reserve the right to dispose of defective material in any

manner considered fit by him (Purchaser), at the sole risk and cost of the supplier. Any sale

proceeds of the defective material after meeting the expenses incurred on its custody, disposal

handling etc., shall however be credited to the supplier’s account and set off against any

outstanding dues of the purchaser against the supplier. The warranty for 12/18 months shall be

one time

General Manager / P&D,Cum- Member Secretary,UHBVN, Panchkula.

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PART III

PANEL DETAILS

A. TRANSFORMER PANELS:

I. Protection scheme as per para 7.1

II. A multi contact auxiliary relay suitable for 24 V D.C. for inter tripping purposes.

III. The provision of supervision scheme, alarm scheme, mimic scheme, metering scheme and

control scheme on this panel shall conform to applicable items of paras 2,3,4,5, & 6

respectively.

B LINE PANEL:

I. Protection scheme as per para 7.2

II. The provision of supervision scheme, alarm scheme, mimic scheme, metering and control

scheme on this panel shall conform to applicable items of pares 2,3,4,5 & 6 respectively

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ANNEXUR-‘A’

GUARANTEED TECHNICAL PARTICULARS OF 33 KV TRASFORMER AND FEEDER CONTROL AND RELAY PANEL & FOR GROUP CONTROL OF 2 Nos. OF 33/11 KV TRANSFORMERS

I. Indicating instruments:

1. Make

2. Type3. Size

4. VA burden

a) Current Coil

b) Potential Coil

5. Power consumption

a) Current Coil

b) Potential coil

6. IS standard grade of accuracy

7. Range of dial

8. Limits of error in effective range

9. Calibration for

a) C.T. ratio

b) P.T. ratio

10. Finish

11. Short time overload capacity.

12. Descriptive leaflet reference Nos. submitted.

13. Type & make of selector switch for ammeter.

II Circuit breaker control switches:

1. Make:

2. Type:

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3. Type of handle provided:

4. No. of position:

5. No. of contacts.

a) Normally closed

b) Normally opened.

6. Whether spring return to neutral or stay put type?

7. Type of lock provided.

8. Descriptive leaflet number submitted.

III. Semaphore indicator (for circuit breaker, isolator & earth switch)

1. Make

2. Type

3. Diameter of the disc.

4. Operating voltage

5. Burden

6. Whether latch-in type or supply failure type.


IV. Indicating Lamps:

1 Make

2 Type

3 Operating voltage.

4 Size of lens.

5 Wattage of the lamp.

6 Descriptive leaflet number submitted.

V Switch Board Wiring

1 Insulation of wiring.

2 Wiring conductor size and its material.

3 Size of wiring conductor for:

a. CT circuits.

b. PT circuits.

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c. D.C. supply circuits.

d. Other circuits.

4 Size of earthing bar for safety earthing.

5 Type of terminals used in wiring the panel.

VI Over Current & earth fault relay: 1 Make.

2 Type of relay.

3. Current coil rating.

3 Tap range.

4 Range of high set elements (wherever applicable)6 VA burden:

a. At highest Tap.

b. At lowest Tap.

7 Trip contact rating.

8 Descriptive leaflet Nos. submitted.

VII Auxi liary Relays:

1. Make.2. Type.

3. Capacity of contacts

a. Continuously.

b. For 3 seconds.

4. Operating coil VA burden.

5 Voltage operated or current operated.

6. Number of normally open contacts.

7. Number of normally closed contacts.

8. Contacts hand or self reset type.


VIII. Restricted Earth Fault Relay:

1. Make

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2. Type of relay.

3. Current coil rating.

4. Setting range

5. VA burden:

a. At highest tap

b. At lowest tap


IX. TRANSFORMER DIFFERENTIAL RELAY.

1. Make

2. Type.3. Minimum differential current at which relay operations.

4. Range & steps of bias setting

5. Operating time at twice the relay setting

6. VA burden of the relay

7. Descriptive leaflet No.

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