WORK

Amount

WORK FOR GENERAL MAINTENANCE / SERVICING / REPAIRING OF VARIOUS MAKE 33 KV VCB & 01 NO. 36 KV SF6 CIRCUIT BREAKER INSTALLED AT 132 KV SUB STATION BARABANKI

Following work is to be done in 36 KV VCB of ABB / Alstom / CGL / Siemens / Stelmac make at 132 KV S/S Barabanki with all cost of men, material, T & P etc.: Work Included:- a. Checking, cleaning and lubrication of trip coil and closing coil assembly for freeness of its plunger. b. Checking, de-rusting and tightening of limit switch of charging motor. c. De-rusting and greasing of charging ratchet and Driving pawls. d. Checking of tripping spring and shock absorber. e. Checking of both the holding latch for proper and smooth operation. f. Tightening of all electrical connections of TB, Limit Switch, Contactors, Anti-pumping device. g. Checking and tightening of all foundation bolts, bolts between mechanism and support structure etc. h. Checking of operating rods for tightness of adjustment bolts. i. Checking of IR value of insulating rod of VCB. j. Checking of VI for its vaccum level by DC high pot method by applying 33 KV DC through VACCUM INTERRUPTER TESTER. k. Checking of contact resistance of all the three contacts of VCB. l. Measurment of opening and closing time of Breaker.

Repairing / Overhauling including rewinding alongwith replacement of Carbon Brushes of Spring Charging Motor of VCBs after necessary dismantling and re-fixing.

Repairing and Overhauling of Air Compressor of 145 KV SF6, CGL make circuit breaker installed on 63 MVA Transformer-I Bay at 132 KV S/S Barabanki.

Repairing and Overhauling of 36 KV SF6 CGL Make Circuit Breaker of 2 x 5 MVAR Capacitor Bank-I. Work includes: Complete dismantling of pole units, checking, cleaning of its contacts, replacement of pole O-rings and Refitting the poles after application of micro-carbon grease over contact surfaces; Erection of pole units on the breaker structure; Connection of SF6 gas pipe lines and apply vacuum by help of vacuum pump upto specified value and maintain it for 24 hours to check no loss of vacuum then fill SF6 gas upto specified value and check no gas leakage by help of SF6 gas leakage detector; Overhauling of mechanism assembly by cleaning, greasing and proper adjustment. Dismantling of close/trip coil assembly and cleaning of its plunger assembly and adjust its proper air gap. Dismantling of horizontal rod assembly, its pins, cleaning and lubrication; Checking spring charging motor and replace its carbon brushes if required. Checking satisfactory close/ trip operation of the breaker both from local and remote and close/trip timing by digital timer.

SWITCHGEAR AND TRANSFORMER CARE CENTRE

lodhi switchgear enterprises