bids are invited for operation and maintenance of substation - complete system, activities carried out during servicing 1. vacuum circuit breaker (vcb) 2. transformers (oil- type) 3. transformers (dry-type) 4. air circuit breakers (acb) 5. protective relays 6. electrical testing 01 visual inspection of the breaker 02 cleaning all parts for dust, deposits, foreign particles etc. 03 lubrication of moving parts of the vcb (with grease) 04 oiling of closing and tripping coil, if required. 05 checking of aux. switches (test/ serv., sp. charging limit switch) 06 checking of front drive key operation (test/ service position) 07 checking of tripping and closing coil resistance 08 checking of roller gap 09 checking of damping gap 10 checking of cir clip, lock washer 11 checking of pole and all type insulators 12 checking of earthing sliding contact 13 checking of control plug 14 checking of spring charging mechanism (manual/ electrical) 15 alignment of cb moving parts 16 mechanical and electrical operation at breaker 17 sp. charging motor coil resistance