A 1.3-kVA, 408 / 129 -volt distribution transformer has the following equivalent resistance and leakage-reactance values referred to the primary: rep = 1.7 ohm; xep = 7.3 ohms. This transformer has core losses of 400 watts. If this transformer is operating at full-load with 0.52 power factor lagging, what is its percent efficiency at this loading?

A 1.3-kVA, 408 / 129 -volt distribution transformer has the following equivalent resistance and leakage-reactance values referred to the primary: rep = 1.7 ohm; xep = 7.3 ohms. This transformer has core losses of 400 watts. If this transformer is operating at full-load with 0.52 power factor lagging, what is its percent efficiency at this loading?

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.16P: A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters:...

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