bids are invited for installations for nonoperational area amc for e and m installation for non-operational area , supplying and topping of new insulating transformer oil , servicing of existing acb of various make having capacity of 800a to 1600a , servicing of existing 11 kv vcb of various make , filtration of transformer oil including dehydration and removal of cabon , cablibration and testing of idmt relays , calibtration and testing of measuring instruments insulation tester clip on meter earth tester , calibration and testing of buchlotz relay for kv indoor oil cooled , operation and maintenance services of wtp of sand filter carbon filter , replacement of following media for wtp filtering san required for ngmf 135 , replacement of following media for wtp gravel 2-6 mesh ngmf ngs ngma , replacement of following media for wtp activated carbon required for ngma-110 annual maintenance contract of electrical and mechanical total quantity : 5997