4. 70 kVA, 24,000/480-V single phase distribution transformers are connected in A/Y. The open-circuit test was performed, and the following data were recorded: Vo-480 V,Io=4.1 A,Po=945 W The short circuit

test was performed and the following data were recorded: Vsc=1600 V,Isc=1.6837 A,Psc=1050 W a. Find the equivalent circuit parameter of the transformer referred to the high voltage side. b. Find the voltage regulation of this transformer bank at full load, 0.9 PF Lagging. c. What is the transformer efficiency at the previous conditions.

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