REPAIR MAINT REPLACEMNT OF EXTERNAL ELECTRIC SUPPLY NETWORK HT CABLE, DISTRIBUTION SYSTEM VCBs , RMUs, DISTRIBUTION TRANSFORMER AND OTHER CONNECTED WORKS AT AF STN PURNEA UNDER AGE I AF PURNEA

M & L for disconnecting and taking out HT VCB/RMUs panel of capacity 400/630Amp, 350MVA (MES No. & Location as Per Appx 'A' Attached) and to carry out following Periodical Maintenance (i) Overhauling of Spring charge unit including cleaning & removing of scales, soot or any hydroscopic layer accumalated on copper/aluminium bus bar using proper chemical cleaning reagents like CRCs (ii) Checking nuts,bolts, make break operation both mechanically and electricaly smooth including greasing of all moving/ fixed contact,nut & bolts (iii) Checking contact resistance, Internal control wiring, repairing/replacing heating coil removing moisture for all the feeders, (iv) Servicing of Spout insulators safety shutter for effective covering by automatically open/close while draw in/draw out operations, Checking and tightening control wiring and rectifying the defects if any. (v) cheking of earth fault and over current relays testing of relays with the help of relay testing kit (boosting Kit) and resetting of relays as per desire load current reconnecting the cables ,including calibaration of relays. (vi) Checking of tension spring and adjusting for proper tripping and functioning and replacement of U/S parts if required and testing complete for tripping all as directed by Engineer-in-Charge. (Note: Spares required for replacement will be paid and measured separately).

M & L for replacement of under mentioned unserviceable items to be incorporated against item No. 1 :- LED Indicator lamp of voltage Range : 110A - 110 VAC 110D - 110 VDC 240A - 240 VAC 220D - 220 VDC

S&F in repair/replacement of spring Charging Motor suitable of 11 KV VCB 110 V-230 Volt AC supply for the opening and closing of contacts complete all as per sample at site and directed. Make- ABB,Siemens,CGL,Bhel

S&F in repair/replacement of vaccum intrupter bottle as per existing capacity of VCB 110 V-230 Volt AC supply for the opening and closing of contacts complete all as per sample at site and directed.

S&F in repair/replacement of digital Voltmeter (0 to 12 KV size 96x96 mm class 0.5, PTR 11000/rt3/110/rt3 complete all as specified and directed.

Supply and fix three phase over current and earth fault auxillary relay Suitable for CT Secondary 1 Amps or 5 Amps,Aux Supply 77-250V DC/AC (230VAC) suitable for existing breakers including taking down old U/ S relay make: Ashida/Crompton/Ariva or equivalent

Transformer capacity up to 250 KVA

Transformer capacity above 250 KVA upto 500 KVA

Material and labour for Earthing in replacement with galvanised steel earth plate electrode 600x600x6mm thick burried directly in ground, earth pit not less than 2.25mtr deep below ground level with top edge of the plate not less than 1.5mtr below normal ground level connected to GI earth strip of 32x6mm by means of nuts,bolts, checking nuts, washers of galvanised iron or steel all as shown in electrical plate No.3 of MES SSR part-I connected to earthing test point including excavation/earth work in any type of strata, watering pipe with funnel, PCC chamber with PCC cover slab without GI protection pipe all as specified and directed by Engr-in-Charge.