| 1 | Supply , installation , Testing and commissioning of outdoor type step down,copper wound, Power transformer as per IS-2026 & IEC : 60076-1 :2000, 66/11KV, 5 MVA , ONAN, 3 phase , 50 Hz, double copper wound, core type with low loss, non ageing, high permeability, prime grade, CRGO core material M4 grade or better with BIS certification, perfectly insulated and clamped to minimise noise and vibration, Delta/star vector group DYn11, ON LOAD Tap changer on HV side to vary secondary voltage from (+) 5% to (-) 10% in 12 steps @ 1.25%. The OLTC shall conform to IS 8468/IEC 60214 (Part 1& 2). The 66KV and 11 KV bare condensor type bushing oil filled shall be provided. Thermal sensors and necessary arrangment to get the data on SCADA on Modbus protocol shall be provided.The insulating oil shall be unused inhibited Type A, High Grade conforming to IS 335/ IEC-60396-2020. The transformer shall be designed with particular attention to the suppression of voltages especially the third and fifth harmonic so as to eliminate wave form distortion and any possibility of high frequency disturbances, inductive effects or of circulating currents, between neutral points of different transformer stations reaching such a magnitude as to cause to interference with communication circuits. The transformer shall have following accessories and fittings etc. all as directed.
(i) Double float Reed type Buchholz Relay(gas operated) with shut off valves at both ends, complying with IS:3637 , 50mm, with two pairs of electrically separated contacts, one pair for alarm and other pair for tripping.The angle of inclination shall be 3 to 7 degree
(ii) Oil temperature indicator 150mm diameter for top oil temperature indication with angular sweep of 270 . Range of temperature should be 0-150 C with accuracy of 1.5% (or better) of full scale deflection, with alarm and trip contact.
(iii) Winding temperature indicator about 150mm diameter for measuring the hot spot temperature of each winding [HV, IV & Tertiary (if applicable)]. It shall have angular sweep of 270 . Range of temperature should be 0-150 C with accuracy of 1.5% (or better) of full scale deflection, with electrical contacts for alarm and trip contacts.
(iv) Sheet steel weather proof Marshalling box of IP -55 construction and shall have following load disconnect switch for incoming power supply from auxiliaries, wiring and termination individualy for Buchholz relay alarm for main tank, winding temp high alarm, oil temp high alarm, tank oil level low alarm, tap change incomplete alarm, wiring and termination individually of remote trip alarm,winding temp high trip,oil temp high trip,Buchholz relay trip or sudden gas and sudden oil pressure relay trip , Cubicle illumination lamp with door switch and space heater with thermostat and ON/OFF switch
(v) Magnetic oil level gauge with low level alarm contact.
(vi) Pressure release valve (PRV) with trip contacts.
(vii) Conservator with oil filling hole with cap and drain plug and with built in diaphragm to avoid direct air contact with transformer oil & diaphragm rupture detection relay.Conservator tank shall be provided with two separate compartments( with partition barrier). One for main transformer tank and other for OLTC compartment.
(viii) Magnetic Oil level indicator 150mm dia with minimum level marking.
(ix) Thermometer pockets with thermometer.
(x) Silica gel breather with silica gel
(xi) Air Release plug.
(xii) Lifting Lugs
(xiii) Earthing terminals
(xiv) Bi-directional Rollers- 4No | 1.00 | Each |
| 2 | (xv) Anodized aluminum rating and diagram plate.
(xvi) Top filter valve
(xvii) Bottom drain -cum- filter valve.
(xviii) Jacking lugs
(xix) Insulation level KV Peak- HV-325KV and LV- 75KV
(xx) Insulation level (power frequency with stand) HV- 140KV, LV-28KV
(xxi) System fault level 31.5KA at 66KV
(xxii) Single float Bucholz relay/oil surge relay with alarm contact for OLTC
(xxiii) No load losses and load losses at rated voltage and frequency- Not more than 40 KW
(xxiv) % Impedence at 75 degree centigrade at rated current and frequency - not more than 7.15
(xxv) For electrical operation of OLTC from local as well as remote, motor operated mechanism shall be provided. The tap changer shall be provided with over-current protection in order to prevent the tap-change operation during a short circuit. The Local OLTC Drive Mechanism Box shall house all necessary devices meant for OLTC control and indication. The diverter switch or arcing switch shall be designed so as to ensure that its operation once commenced shall be completed independently of the control relays or switches, failure of auxiliary supplies etc. To meet any contingency which may result in incomplete operation of the diverter switch, adequate means shall be provided to safeguard the transformer and its ancillary equipment. The current diverting contacts shall be housed in a separate oil chamber not communicating with the oil in main tank of the transformer and the chamber shall be designed to withstand the vacuum. It shall be complete with the following:(a) A circuit breaker/contactor with thermal overload devices for controlling the AC Auxiliary supply to the OLTC motor (b) Emergency Push Button to stop OLTC operation (c) Cubicle light with door switch (d) Anti-condensation metal clad heaters to prevent condensation of moisture (e) Pad locking arrangement (or locking arrangement suitable for long term operation) for hinged door of cabinet (f) All contactors relay coils and other parts shall be protected against corrosion, deterioration due to condensation, fungi etc. (g) The cabinet shall be tested at least IP 55 protection class.
(xxvi) Remote tap changer control panel (RTCC)
(xxvii) Automatic voltage regulator relay (AVR). It shall be supplied together with the timer and under voltage relay.
(xxviii) The contractor shall submit drawing of transformer for approval of Accepting Officer within 30 days of placing of work order. | | |
| 3 | Supplying, installation, testing and commissioning of INDOOR TYPE control and relay panel for the protection and operational working of out door 66KV/11KV , 5MVA transformer and 66 KV feeder all as directed and specified by E-in-Charge . It must be manufactured by OEM of transformer or its authorised system integrator (having type test report), made up of 2mm thick MS sheet, consisting of separate vertical stationary front panel with equipment mounted thereon & having wiring access from the rear. Each cubical assembly shall be provided with double leaf doors as rear having handles with built in locking facility.The height of the panel shall not be more than 2250 mm .The control & relay board shall be on panel at front. It is responsibility of the bidder to ensure that the equipment specification and unspecified complimentary equipment required for completeness of protection & control schemes be properly accommodated in the panels. Test of relays shall be carried out based in general guide lines specified in CIGRE committee for all relays. The drg of panel shall be submitted for Approval of Accepting Officer within 30 days of placing of work order along with drg of power transformer. The drawing shall consists of all following items including any other items required for functional requirement of panel and its acessories
a. BCU C264 / Micom P3F
Rack 4U, 80 TE, IP20
front bus mother board 80TE
Power supply Vnom: 220 VDC and 230VAC / Nominal wetting voltage for 2 DI: 220 VDC - 2 serial ports
CPU275 (Type 4), with 2*Ethernet RJ45, 128Mb FlashMem, 256Mb SDRAM, 50 ppm Oscill
Front Face with LCD & LEDs (80TE) detachable up to 5m
16 DI 1 ms, 220VDC
10 DO Board (8NO+2NO/NC)
4I and 5U direct acquisition board from CT/VT Ration 5 or 10 Amp
b. Numerical relay as IEC 61850 with following features:- Two winding differential , overload Protection with 3 Nos O/C elements with setting range (50-200%)of 1A, E/F protection with setting range (10-40%) of 1 A, REF protection, over flux protection over volatge and under voltage protection tripping logic disturbance recorder,LBB (Break failure protection)
c. Supervision Relay - (AC Supply Supervision) 200ms<drop off time<400ms, 4contacts, Available ratings: 110, 220 VDC
d. Supervision Relay - (DC Supply Supervision) 200ms<drop off time<400ms, 4contacts, Available ratings: 24, 48,110, 220 VDC
e. DC CHANGEOVER RELAY
f. Supervision Relay - (Trip Circuit Supervision) ; 200ms<drop off time<400ms, 2 contacts, Available ratings: 24, 48,110, 220 VDC
g. Tripping Relay - with electrical hand contacts & following flag; High Burden. Operating time<10ms (8 Contacts), Available ratings: 24,48,110, 220 VDC. All tripping relays can have a high or a low burden configuration. Auxiliary Relay - with S/R contacts & H/R flag; Operating time<20ms. (8 Contacts), Available ratings: 24,48,110, 220 VDC
h. VOLTAGE SELECTION RELAY
Tripping Relay - with E/R contacts & following flag. High Burden. Operating time<10ms..(8 Contacts), Available ratings: 24, 48,110, 220 VDC. | 1.00 | Each |
| 4 | j. Discrepancy switch multi modeI with built in LED lamp and flasher relay, 220V DC supply -DCS-65x65mm, Knob size: 45mm Dia
k. Semaphores 36 mm without LED
l. Annunciator - micro controller based, Aux. Volt :88 - 285V AC/DC, Annunciator In-Built Inside Annunciator & Internally Wired] Window size : 72X34MM options:AC & DC fail annunciation , repeat relay, relay card,RS485 Communication on MODBUS protocal
m. Multi function meter, CT/PT SEC: 1A/110V CT/PT Primary: User programmable Multi function meter 3phase 3 element 4 wire, Class: 0.5, CTR: user programmable/1A, PTR: user programmable/110V, comm: MODBUS via RS485 , auxilary voltage :(100-250V) DC
n. Analog Ammeter - 96 mm sq , Class :1.0
o. Voltmeter selector switch, 6 position (RY-YB-BR-RN-YN-BN)
p. Auxillary Contractor 220VDC, CAD32MD COIL :220V DC contacts : 3 NO & 2 NC contact rating : 10 Amp
q. Auxiliary Relay - with S/R contacts & H/R flag.Operating time<20ms. (4 Contacts ), Available ratings: 24, 48,110, 220 V DC
Miniature relay, Auxillarycontacts: 4(C/O), Auxillary supply 220V DC
r. Relay test block
(s) LRS/LBB IN/OUT SWITCH
LR-2P-20W-SP-LA-25A - TYPE: Stayput, 20 WAYS, 2 positions lockable at all positions, circuit label :local * remote, handle: Pistol , 4 + 4 Contacts, Non-Lockable selector switch 8 ways, 2 positions, stayput, with pistol grip handle t. Auxillary plug in type relays with change over contacts , high speed trip relay , MCBs, Electric hooter 110v DC, Digital multi function meter to show three phase current and voltage, power factor, frequency, three phase energy with SCADA compatable, LED indicator lamps and with standard parameters. illumination lampwith ON/OFF with door switch, Space heater with thermostat and toggle switch, Earth bus and terminal blocks,Three pin 15A socket with ON/OFF switch complete all as specified and directed by Engr-in-Charge. | | |
| 5 | Notes for item No. 01 & 02 :
(i) Any item specifically not mentioned but requred technically for proper functioning is deemed to be included in quoted rates
(ii) The routine test on transformer shall be carried out at OEM premises by rep of Accepting Officer along with rep of contractor before dispatch. The Contractor shall poroduce type test report of similar capacity power Transformer or nearest standard size capacity available.
(iii) The drg of transformer shall be submitted by contractor to Accepting Officer for approval before procurement. OEM must have NABL accredited LAB for testing and in house slitting machine and core cutting facilities and certificate to this effect issued by OEM shall be submitted to AO at the time of Approval of Drgs.
(iv) The erection, testing and commissioning of transformer shall be performed under strict supervision of representative of OEM and certificate of this effect will be given by OEM shall be submitted by contractor to GE.
(v) Core material shall be directly procured either from the manufacturer or through their accredited authorised dealers and not through any agent. The maximum flux density in any part of the cores and yoke at normal voltage and frequency shall be such that it should under 10% over voltagecondition should not be more than 1.9 Tesla. The supplier shall provide saturation curve of the core material, proposed to be used. PVr of core shall be submitted by OEM to GE before routine test. Wdg shall be made with 99.9% pure electrlytic grade copper. | | |