manufacturing, testing, supply and erection and commissioning of 3 nos. 25 mva, 11 / 132kv generator transformers for mukerian hydel project, talwara, punjab manufacturing, testing, supply and erection and commissioning of 3 nos. 25 mva, 11 / 132kv generator transformers for mukerian hydel project, talwara, punjab , part i : supply , 25 mva, 11 / 132kv, onan cooled, oil immersed outdoor type generator transformer suitable for 3-phase, 50 c / s frequency, delta-star connected in accordance with iss vector group yd 11 with neutral solidly earthed on hv side. the transformer will be fitted with off ckt tap changer of easun-mr / telk / bhel / ngef / cgl / ctr / paragon associates / alwaye make type 66 kv, 300 amps rating for voltage variation on hv side to give 142.5 kv, 139 kv, 135.5kv, 132 kv and 128.5 kv with lv constant. percentage impedance on 25 mva base at 75 deg.c shall be as 10% + tolerance as per is-2026 part-ii latest edition. the transformer shall be able to operate continuously for 10% overload capacity. the transformer shall be dispatched oil filled. transformer oil ( napthenic base ) for radiators& conservators etc. alongwith 10% extra quantity shall be dispatched directly in non-returnable epoxy coated steel drums. the transformer shall be complete with all fittings and accessories as per specification. the following extra spares with each transformer shall form part of supplies , hvline end bushing complete , lv line end bushing complete , hv neutral end bushing complete , complete sets of gaskets , wti with remote indicator , magnetic oil level gauge , oti with remote indicator , silica gel container along with silicagel ( for one time filling ) for main tank , pressure relief valve , buchholz relay , dial type thermometer for oti , switches, fuses, relays for electric control ckt. , short circuit test charges for 1 no. gt ( if applicable ) , part ii : erection and commissioning , erection, commissioning of 25 mva, 11 / 132kv, onan cooled, oil immersed outdoor type generator transformer.