4.32 Consider a 75 kVA, 2400/240 V, 60 Hz transformer. Assume that the open-circuit and short- circuit tests were performed on the transformer and that the following data were obtained: Open-Circuit Test (on Primary) Short-Circuit Test (on Primary) Voltmeter Va=2400V V= 200 V I=0.50 A P =75W Ammeter =31.25 A Wattmeter P = 800 W Also assume that the transformer operated at full load with a 0.92 lagging power factor. Note that the given power factor belongs to the load, not to the transformer. Determine the following: (a) The equivalent impedance, resistance, and reactance of the transformer, all referred to its primary side (b) Total loss, including the copper and core losses, at full load (c) The efficiency of the transformer (d) The percent voltage regulation of the transformer

4.32 Consider a 75 kVA, 2400/240 V, 60 Hz transformer. Assume that the open-circuit and short- circuit tests were performed on the transformer and that the following data were obtained: Open-Circuit Test (on Primary) Short-Circuit Test (on Primary) Voltmeter Va=2400V V= 200 V I=0.50 A P =75W Ammeter =31.25 A Wattmeter P = 800 W Also assume that the transformer operated at full load with a 0.92 lagging power factor. Note that the given power factor belongs to the load, not to the transformer. Determine the following: (a) The equivalent impedance, resistance, and reactance of the transformer, all referred to its primary side (b) Total loss, including the copper and core losses, at full load (c) The efficiency of the transformer (d) The percent voltage regulation of the transformer

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter29: Dc Generators

Section: Chapter Questions

Problem 1PA: You are working as an electrician in a large steel manufacturing plant, and you are in the process...

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