supply of 500 kva, 11 / 0.415 kv delta / star indoor type transformer vector group - dyn-11, type of cooling- onan, copper wound with all accessories and confirm to is 1180 pt.1 2014 or latest. offload tap changer for variation of hv voltage from +5% to -10% in steps of 2.5% with all standard fittings as per clause 20.1 of is 1180 ( part-1 ) and oil temperature indicator & winding temperature indicators. drain-cum-sampling valve ( 3 / 4 nominal size thread is:554 ) of steel with plug, energy efficiency level-3 & above, conforming to is 1180 ( part.1 ) :2014 with amendment no.1, 2, 3, 4 & latest. following has to be submitted along with supply of materials: i ) type test report as per is:1180 ( part 1 ) of transformer having same rating, make ( & model if any ) and design from nabl accredited lab. ii ) routine test certificates as per is:1180 ( part 1 ) . iii ) special test certificates as per clause 21.4 sl.no. ( a ) , ( c ) , ( d ) & ( e ) of is:1180 ( part 1 ) . tc & gc will be supplied along with the material as per irs terms and conditions. only oem should supply this material along with its past credibility in govt. organizations. [ warranty period: 30 months after the date of delivery ]