KMC/S_D/KGPS-8R/23-24

Amount

Racking down & drawing out of OCB from 2 panel , 11 KV , 400A HT Switchgear after tripping the OCB manually & keeping the OCB in a workable position inside the room.

Complete dismantling of all the mechanical parts of the H.T Switchgear after removing to a workable position inside the sub-stn. After dismantling of all the components like roller, main latch, trip latch, s.s. spring, self spring, ratchet etc should be properly overhauled by petrol & insulating oil to remove carbon particles & after overhauling re-fix as per existing way for inter locking arrangement, bush, spring etc.

Servicing & overhauling of shutter mechanism including replacement of spring, pinion etc as required (Busbar side).

Supply & fitting fixing of shunt trip coil.

Supply & fitting fixing of LED Indicating lamp with holder (Neon) including necessary internal wiring.

Complete panel wiring by supplying of 1.1kv grade, PVC insulated copper wire of 2.5 sq. mm (Make : KEI, Havells, Finolex) laying inside control circuit panel through PVC front cover cable tray with numbering ferrules, socketing, crimping joints for measuring instrument relay including supply & fixing of 2 nos. push button, 12 nos 6-10 Amps HRC fuse cartridge, binding tape, flexible PVC pipe etc. The C.T’s secondary connection should be short circuited. Reconnection of H.T cable terminal joint.

Supply & fitting fixing of power-pack unit with necessary control wiring.

Dismantling of oil tank & draining out of insulating oil from OCB tank to another container & keep it in safe custody for filtration purpose.

Acidity testing of the insulating oil by an authorised reputed agency & test result in duplicate to be submitted to the Deptt.

Removing of pitting from H.T contact , cleaning of the main V & finger contacts by CTC, white petroleum jelly, fresh markin cloth etc to render free from carbon & other particles.

Cleaning of sludge , carbon particles, metal dust etc from OCB tank by fresh hot oil jet pressure, soft brush, markin cloth etc. and refitting oil tank including other dismantled parts.

Dehydration & filtration of the insulating oil by oil filter machine & BDV testing should be done for 40KV/1 minute as per relevant IS .

Hire charges of insulating Oil BDV testing machine.

Supply & delivery of busbar separator of both end circular type of fibre glass make.

The trip circuit mechanism of the OCB shall have to be checked properly & adjustment of all linkage for proper functioning.

Servicing, testing, calibration of Overcurrent, Earth Fault CDG type relay.

Painting of the Switchgear surface after proper cleaning by emery paper, brush petrol etc by one coat of primer & two coats of synthetic enameled paint of approved quality with necessary marking.

Testing & commissioning of switchgear panel with following test : Trip test through relay , Megger (IR) value test , High Voltage test.

Tripping the OCB manually and after tripping open out the primary side cable box cover of 400 KVA , 11KV/415V Transformer and discharge the HT cable using Earth-stick by appropriate earth connected by copper cable properly to the earth-bar.

After discharging the primary side and secondary side of the transformer, open out all the cables from HT & LT side making proper tag marking of all the cable.

Dismantling of top cover, side cover, guard bar etc.

Disconnection of the HV & LV connection of winding from bushing terminal ends and measurement of insulation resistance.

Checking of rusting, corrosion, and deterioration of the insulation, varnish or paint. Winding to be inspected for contaminants, especially on insulating surfaces or where they could restrict air flow. Check for loose connections, condition of tap link, terminal boards and for the general condition of the transformer. Check for signs of overheating and tracking or carbonization marks. Reinsulation of the HT winding section as necessary.

The windings may be cleaned with a vacuum cleaner, a blower, or with compressed air or nitrogen. The compressed air or nitrogen should be clean and dry and should be applied at a relatively low pressure (not over 25 lbs/in2 ). Lead supports, tap changers and terminal boards, bushings, and other major insulating surfaces should be brushed or wiped with a dry lint-free cloth.

Testing of transformer including Insulation resistance test (LV side by 1000V, HV side by 5000V IR tester), High Voltage test at 12KV rectified DC, Earth resistance test for Neutral & Equipment Earthing.

Reconnection of Winding & Outgoing cables to the terminal bushing including neutral earthing connection.

Refitting of top cover, side cover, guard bar etc. after cleaning both side properly .

Painting of the Transformer enclosure after scrapping the existing coating by one coat of zinchromate red-oxide primer & after drying out two coats of synthetic enameled light gray paint as per direction of E.I.C.

M/S S S UDYOG

SARKAR ENTERPRISES