SPECIAL REPAIR REPLACEMENT FOR CERTAIN TRANSFORMER VCB AT SEVOKE MIL STN UNDER GE SEVOKE ROAD

Amount

Schedule 'A'

Supplying , transporting, erectioning,testing and commissiong of 36 KV, 1800MVA, 33kV, 1250A, 50Hz voltage class outdoor type VCB, circuit breaker for use on system voltage 33 KV. The circuit breaker and accessories shall conform to IEC-62271-100 or IS 13118 and other relevant IEC/IS standard. The circuit breaker shall be complete with terminal connection operating mechanism control cabinets piping interpole cable accessories like gland, terminal block, lugs, necessary steel support structure for CB and control cabinet The circuit breaker shall be required to performs as per technical parameters given below. (a) Installation - Outdoor, 3-pole, Live-Tank, Porcelain Clad, Switchyard Breaker (b) Rated Voltage - 36 KV (c) Rated Current - 1250A (d) Power frequency with stand voltage (KV rms)- 70 KV (e) 12/50 microsecond lighting impuls with stand voltage (KV Peak)-170 kVp (f) Rated short circuit current breaking capacity (3 Sec ) at rated voltage specified 31 KA (g) Control Voltage incl. trip/close coil - 110V DC (h) Spring Charging Voltage - 230VAC (j) Symmetrical interrupting capacity (KA/RMS) 31.5 KA (k) Rated short circuit Making Current (KAP)-80A (l) Short time carring capacity for 01 Sec -31.5KA rms (m) Out of phase breaking capacity (KA rms) as per IEC (n) Rated operating duty as per IEC(o) Temp rise over the design ambient temperature -As per IEC 62271-100 (r) Operating Mechanism -Spring (s) Creepage distance as per IEC-900mm (t) No of trip/close coil 110 V DC-02 Nos (u) Tripping system - 110 V DC

Supply, installation laying & testing of 33KV relay & remote control panel indoor type for Transformer . The panel shall be with back access double door arrangement, dust and vermin proof, IP-4X class protection and made 16 SWG , CRCA MS sheet powder coated finsh over one coat of red oxide primer both side operating type, including internal wiring using 1.1kV FRLS insulated multistrand cable (2.5sqmm for CT/PT circuit, 1.5sqmm for Control circuit), numbered and colour coded as per IS-5578/1984 having suitable entry for cable consisting of the following:- (A) Main Protection Relay shall be a Numerical Transformer Differential IED Relay generally confirming to IEC60255, microprocessor based protection scheme for detecting, indicating and tripping the breaker on various faults Transformer Differential, and OverCurrent+Earth Fault protection for HT/LT side, Alarm/Trip scheme for Buccholz & OTI & WTI & PRV. The Relay shall have complete bay control features incl. Large LCD display for displaying Feeder SLD (position indication), integrated ON/OFF control function, three phase current measurement, disturbance recorder, event log and fault record with non-volatile memory, self-supervision, ethernet based GUI on Windows' Internet Explorer without requiring any additional software. The relay shall have sufficient analogue channels to receive all CT-inputs to achieve Differential, with internal summation and vector matching capability. The relay shall have sufficient binary inputs and outputs (8BI/10BO) to receive and issue external commands. The relay shall be fully integrated with the feeder, internally capturing feeder statuses incl. Breaker On/Off/Spring.Chrgd/, Line-Current etc. and display the same locally on a built-in back-lit LCD screen as a Single-Line-Diagram and suitably labelled status LEDs. Relay shall have facility to locally Trip/Close the breaker as a backup to TNC switch provided seperately on the CRP. TCP/IP based WebHMI shall be integrated part of relay for remote setting without requiring any special relay software. (B) Aux. Protections like Trip Circuit Supervision, Circuit Breaker Failure protection, master trip be provided as separate relays as approved by engineer-in-charge. Transformer Aux. Protections signals like Buccholz, OTI, WTI, PRV Alarm, Master trip, DC, fail, TCH, etc. Note: To in integrated in numerical relay. (C) Metering, (i) Electronc trivector meter . Accuracy Class 0.5, (ii) Digital Ammeter (D) LED Indicating Lamp, (i) Breaker - On/Off/Trip/SpringCharged, (ii) Mains - R/Y/B Phase Available (iii) Other - AC Available, DC Available, Trip Circuit Healthy (E) Control, (i) Trip/Neutral/Close (TNC) Switch, lockable type - 01no., (ii) Local/Remote Switch - 01no., (iii) Main Protection Relay should have provision of tripping of breaker in case of failure of TNC switch. (F) Aux. Items, (i) Tripping and Control circuit operating at 110VDC, Spring charging, space heater, CFL illumination circuit, operating at 230VAC, suitably isolated and protected via fuses/MCBs, (ii) 16-Window Annunciator with Hooter and Ackn/Reset button for Buccholz/OTI/WTI/PRV Alarm/Trip, OC TRIP, EF TRIP and other Indications as prescribed by engineer-in-charge, (iv) Earth bus, tinned plated copper, 25x6mm (G) Transformer Differential scheme to be integrated by contractor using CT inputs from 33kV and 11kV side. Associated control wiring supply, laying, termination is in scope of contractor. Contractor to submit various calculations and details justifying the a`dequacy of the parameters considered (like line burdens, knee point voltages, CT-Ratios etc.) for prior approval of Engineer-in-charge. (H) Aux Relays: , (i) O/C and E/F relay with communication port- 01, (ii) High speed master trip relay- 01, (iii) Trip circuit supervision relay, (iv) PT fuse relay-01, (v) DC fail relay, (vi) Buccholz relay, (vii) OTI & WTI & PVR relay, (viii) DC fail, (ix) Trip ckt supervision relay. Note: To in integrated in numerical relay.

Supplying, installing, testing and commissioning of Indoor arc-proof Draw-Out Vacuum Circuit Breaker Panel, rated for 11kV, min 630Amp, 26.3kA/3-sec, comprising of 01 no. Incomer, 01no. Bus Coupler and 01 Nos. riser Outgoing fully encapsulated pole VCB Panels, confirming to IEC 62271-200, Internal Arc Classified IAC AFLR – 26.3kA for 1sec, Accessibility Class LSC2B-PM Class, comprising of min 630Amp, continuous rated Copper busbars and droppers, 02nos. Rack-In-Rack-Out Handles, structure made from AluZinc/GI sheets to prevent corrosion and rusting. The complete panel incl. HT and LT chamber shall be manufactured by approved OEM at its own facility. License parter, system integrator, panel builder, half-panel concept is not allowed. The Board shall consist of following panels: (A) 01 x Incomer Panel, each comprising of :-, (i) 11kV, 630Amp, 26.3kA/3-sec, Draw-Out Vacuum Circuit Breaker as per IEC-62271-100. Vacuum Circuit Breaker having 01 Nos. encapsulated vacuum bottles of same make as of circuit breaker, motorized spring charging mechanism (230VAC) with integral spring charging handle for manual charging, associated push-buttons, anti-pumping feature, and associated Shunt Trip/Close Coils (110VDC), (ii) Current Transformers 11kV, 200/100-5-5, Core1: Class 5P10, 5VA, Core2: Class 0.5, 5VA. The 'PS' core will be of suitable knee point voltage and ratio so as to succesfully implement Transformer Differential protection scheme for the upstream power transformer., (iii) Potential Transformers, rear and bottom Draw-out type for easy maintenance, 11kV/rt3:110V/rt3, 50VA, Cl.0.5 with associated gun-type HRC fuses and MCBs for HT/LT isolation - Set of 03nos. , (iv) Main Protection Relay shall be numerical IED Relay confirming to IEC60255, having 04CT+03PT Inputs with microprocessor based protection scheme for tripping the breaker on various faults like , (1) Over-current or earth-fault in any of the three phases, , (2) circuit-breaker-failure alarm, (3) tripping-circuit-failures, The relay shall be fully integrated with the feeder, internally capturing feeder statuses incl. various status, Line-Current, Line-Voltage etc. and display the same locally on a built-in back-lit LCD screen as a Single-Line-Diagram with power & frequency measurements and suitably labelled status LEDs. , TCP/IP based WebHMI shall be integrated part of relay for remote setting without requiring any special relay software., v) Metering Equipment incl. 01 x Digital Voltmeter (Acc.Cl.0.5), 01 x Digital Ammeter (Acc.Cl.0.5), 01 x Tri-VectorMeter (Acc.Cl.0.5), (vi) Indications - LED for Breaker ON/OFF/TRIP/Spring-Charged/R-Y-B, 08-Window Annunciator with hooter, (vii) Control Equipment incl. 01 x TNC Switch, 01 x Emergency Trip Push Button, MCBs for AC/DC isolation as required, (viii) Other accessories incl. Space Heater with thermostat for breaker, busbar, LV panel and cable chamber, 3-Pin socket with switch, CFL lamp., (ix) Suitable Disconnecting Link type terminal arrangement shall be provided for interfacing PS-Class CTs installed in the panel with Transformer differential relay situated in the 33kV CRP for achieving the required protection. (B) 01 x BusCoupler Panel, each comprising of :-, (i) 11kV, 630Amp, 25KA/3-sec, Draw-Out Vacuum Circuit Breaker as per IEC-62271-100. Vacuum Circuit Breaker having 03nos. encapsulated vacuum bottles of same make as of circuit breaker, motorized spring charging mechanism (230VAC) with integral spring charging handle for manual charging, associated push-buttons, anti-pumping feature, and associated Shunt Trip/Close Coils (110VDC), (ii) Metering Equipment incl. 01 x Digital Ammeter (Acc.Cl.0.5) (iii) Indications - LED for Breaker ON/OFF/TRIP/Spring-Charged., (iv) Control Equipment incl. 01 x TNC Switch, 01 x Emergency Trip Push Button, MCBs for AC/DC isolation as required, (v) Other accessories incl. Space Heater with thermostat for breaker, busbar, LV panel, 3-Pin socket with switch, CFL lamp., (vi) MCBs for HT/LT isolation - Set of 03nos. Space Heater with Thermostat included. R-Y-B Phase LED indications. Isolation MCB and related wiring included. (C) 01 x Outgoing riser panel, each comprising of :- (i) Accessories incl. Space Heater with thermostat for breaker, busbar, LV panel and cable chamber, 3-Pin socket with switch, LED lamp. NOTE :- The all above panel consist of the followings:- (i) Suitable Disconnecting cum Shorting Link type terminal arrangement in Incomer panels shall be provided for interfacing PS-Class CTs installed in the panel with upstream Transformer differential relay situated in the 33kV CRP for achieving the required protection. Knee point voltage, CT-Ratio and other details to be submitted by manufacturer. (ii) Make of panel: ABB/CG/Schneider/Siemens., (iii) Adapter panel is required if new panel not matching existing panel designs and rates of adapter panel if required deemed to be included in above quoted retes.

M/s AHMED ENGINEERING