bids are invited for periodical repair maintenance and operation of power supply - periodical repair maintenance and operation of power supply equipment dg sets and sub station equipments ups installed at new power house phase i and phase ii and other lt ht network at the airport nav aids site etc involving repair maintenance and operation attending to complaints fault break downs and taking rectification action ensuring serviceability satisfactory working condition of the system preventive maintenance of system and maintenance of records documentation etc as per detailed specification terms and condition covered under this contract on all days including sundays and holidays , operation and maintenance of roof top solar plant - operation and maintenance of roof top solar power plant of total capacity 400 kwp with plants of varying capacities installed at roof tops of different buildings city side operational area including proper cleaning of solar pv modules tightening of module mounting structure maintenance of electrical equipment logging of data recharging of all sim cards of wi fi system including its maintenance for remote monitoring maintenance of lightning arrestor system and earthing system , repair of earth pits - repair of earth pits including supply of funnel ci ms cover plate reducer and masonary work as required and marking with paint on earth pits as directed by aai complete in all respect and submitting test report to aai , supply of transformer oil - supply of transformer oil suitable for transformers ranging from 63 kva to 2000 kva and conforming to relavant specifications , dehydration and filtration of transformer oil - dehydration and filtration of transformer oil at site including testing the bdv dielectric strength prior and after testing at site including topping up if required and submission of test report transformer oil for toping up will be supplied by department , provision of silica gel , service charges for locating pin pointing of faul