q4 Open-circuit and short circuit tests were carried out on athree-phase 20 kVA ?/Y, 415V/183V power
q4 Open-circuit and short circuit tests were carried out on athree-phase 20 kVA ∆/Y, 415V/183V power transformer. The testresults are given: Open-cct test. on low voltage side and 183Vapplied: Primary open circuit Vp = 183V, i/p current 7.1A P =240W Short-cct test, input to the high voltage side connected in Y? VL = 23.8V IP = 16.1A, I/p power = 405W (a) The equivalent circuit referred to the HV side, (b) the full load efficiency with loads at (i) power factorunity, (ii) powe factor 08 lagging, (c) % of full load for max efficiency . . .