Details: supplying, design, loading, unloading, installing, testing and commissioning indoor type floor mounted step down transformer 11000/433 volts (at no load) capacity 250 kva, ac 3 phase 50 hz double copper wound oil immerged naturally cooled with external cooling tube core type delta connected on primary side (hv) and star connected on secondary side (lv) in accordance with vector symbol dyn-11 (vector group) with neutral brought out on secondry side (lv side) and having tapping at 2.5% interval from -7.5% to + 7.5% on hv side having facility to be changed voltage by means of hand operated off load tap changing gear. the maximum temperature rise should not exceed 50 degree celsius in oil and 55 degree celsius in hv/lv winding from ambiant temp when measured by resistance method after continious full load run in ambient temp of 40 degree celcius. the transformer shall confirm is : 1180 and latest relavent is and ecbc marked and shall comprise of the following:-(a) one cable box on hv
Sector: Defense