SPECIAL REPAIR/REPLACEMENT OF 5MVA 66/11 KVA POWER TRANSFORMER AND ASSOCIATED EQPT AT AF STN BHISIANA UNDER GE (AF) BHISIANA

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

(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.

Material and labour for shifting of old unserviceable power transformer 66/11 KV , 5 MVA from plinth , RTCC panel and 66/11 KV control and relay panel to location near MRS with the help of two hydra cranes ( min. 18 ton each ) complete all as directed by Engineer-in-Charge

Material and labour for Testing of power transformer through liasoning with PSPCL authorised centre / agency for testing of transformer and associated equipments of 66 KV bay 5 MVA power transformer by ASE/ Protection division PSPCL bathinda for clearance and installation of equipment complete all as specified and directed by Engineer-in-Charge

Material and labour for testing of oil including collection of final sample of transformer oil for testing of power Transformer (before and after dehydration ) in borosil container of capacity of 5 Ltrs and sending the transformer oil sample to PSPCL oil testing lab patiala by suitable transport by the contractor due care for following tests and submission test report of OLTC & main body complete all as specified and directed by Engr-in-Charge :- (i) Tan Delta Test (ii) Specific Resistance Test (iii) Brake Down Voltage Test (iv) Water Content Test (v) Total acidity (vi) Interfacial tension (vii) Flash point (viii) Sediment or sludge (ix) Dissolved Gas analysis

Supply and laying and connecting up copper strandard armoured double sheathed control cable1100 Volt size 2.5sqmm, 24 Core passing through air, pipe, wall, ceiling trench/duct, etc including necessery connections, complete all as specified and as directed by Engr-in-Charge. Note:- (i) Control cable shall be supported with aluminum spacers and saddles in the existing ducts. (ii) Termination and ferruling shall be done as per approved wiring scheme (iii) Identification tags shall be provided in the starting and finishing end of the cable at an interval of 5 meter through out the cable length. (iv) Suitable copper thimbles and lugs are to be provided for marking the connection to the terminals (v) Rate Quoted by bidder is deemed to be including of item required for safe laying of cable mentioned in note.

Supply and laying and connecting up copper strandard armoured double sheathed control cable1100 Volt size 2.5 sqmm, 12 Core passing through air, pipe, wall, ceiling trench/duct, etc with and including necessery connections, complete all as specified and as directed by Engr-in-Charge. Note:- (i) Control cable shall be supported with aluminum spacers and saddles in the existing ducts. (ii) Termination and ferruling shall be done as per approved wiring scheme (iii) Identification tags shall be provided in the starting and finishing end of the cable at an interval of 5 meter through out the cable length. (iv) Suitable copper thimbles and lugs are to be provided for marking the connection to the terminals. (v) Rate Quoted by bidder is deemed to be including of item required for safe laying of cable mentioned in note.

Supply and laying and connecting up copper strandard armoured double sheathed control cable1100 Volt size 6 sqmm, 04 Core passing through air, pipe, wall, ceiling trench/duct, etc including necessery connections, complete all as specified and as directed by Engr-in-Charge. Note:- (i) Control cable shall be supported with aluminum spacers and saddles in the existing ducts. (ii) Termination and ferruling shall be done as per approved wiring scheme (iii) Identification tags shall be provided in the starting and finishing end of the cable at an interval of 5 meter through out the cable length. (iv) Suitable copper thimbles and lugs are to be provided for marking the connection to the terminals. (v) Rate Quoted by bidder is deemed to be including of item required for safe laying of cable mentioned in note.

Supply , installation and testing over head bus bar /jumpers at receiveing station for 66 KV comprising of 3 feeder bays inclusive of ACSR conductor of suitable size (ZEBRA) comprising of tee clamps Disc insulators, cross arms or any type of clamps and accessories complete all as specified and directed by Engr-in-Charge.

Material and labour for Cable jointing kit for 11 KV (Earthed) grade cable for indoor termination heat shrink type joint complete with jointing material and accessories suitable for 3 core XLPE armoured aluminium conductor cable of size 240 sqmm to 300 sqmm all as specified and directed by Engineer-in-Charge.

Supply, laying & testing cable XLPE insulated, screened, PVC bedded, galvanized steel strip or wire armoured, electric power cables (heavy duty)with stranded aluminium conductor, 11000 volts grade, of size 3 core 300 sq mm all as specified and directed by Engineer-in-Charge

Material and labour for 60KV 10KA POLYMER LA CLASS-3 66KV including 800AMP POLYMER DBCR MOTORISED ISOLATOR WITH EARTH AND AUX. BOX all as specified and directed by Engineer-in-Charge.

Material and labour for cross arms, bracings, supports, clamps, angle iron, flats and back plates fabricated from MS structural steel sections including nuts, bolts and washers of suitable sizes including welding, bending (cold or hot), drilling holes for bolts in any shape or size as indicated or directed and inclusive of two coats of aluminum paint over one coat of red oxide primer, including 66 KV & 11 KV suport insulators for 3 phase system for holding the jumper of 66 KV & 11 KV from transformer body as per site requirement complete all as specified and directed by Engr-in-Charge.

Supply and installation of HT 66 KV, 3 phase, 50 cycles totally enclosed metal clad SF6 switchgear having rupturing capacity upto 350 MVA, overload and earth fault protection, ammeter, voltmeter and of rating upto 630 Amp all as specified and directed by Engineer-in-Charge.