Tender For supply of outdoor type , plinth mounted, distribution transformer, minimum energy efficiency level 3 of rating 250 kva, 3-phase, 11kv/415-240v,50hz, oil immersed, non sealed type (transformer tank body and cover are bolted), copper wound, primary winding in delta and secondary winding in star (vector symbol- dyn11), onan cooled transformer, conforming to is 1180 (part1):2014 with amendment nos. 1,2,3,4 or latest, and supplied with all standard fittings mentioned in clause 20.1 of is 1180 (part 1) latest with condition that drain-cum-sampling valve. oil temperature indicator & winding temperatureindicators will be provided as per clause 20.2 f) of is 1180 (part 1). terminal arrangement: the transformers shall be fitted on high voltage and low voltage sides bushing appropriate voltage and current ratings., low voltage side cable end box required . the high voltage bushings (3 nos.) shall conform to is/ iec 60137. the low voltage bushings (4 nos.) shall conform to is 7421. off-circuit tap changer (applicable for all ratings above 200 kva) for variation of hv voltage from +5% to -10% in steps of 2.5%. following has to be submitted by supplier along with supply of material: (i) type test report of transformer having same rating, make (& model if any) and design from nabl accredited lab as per is: 1180 (part 1) latest. (ii) routine test certificates as per is: 1180 (part 1) latest. (iii) special test certificates as per clause 21.4 sl. no. (a), (c), (d) & (e) of is:1180 (part 1) latest.