8. A 10 power transformer supplies a load 8 kW of power at a power factor of 0.77 lagging at full load. The voltage at the load is 115V. The transformer has 1200 turns on its primary and 450 windings on its secondary. The iron loss is 325 Watts and the primary copper loss is 150 Watts and the secondary copper loss is 260 Watts. Find a) The full load apparent power and the secondary and primary currents at full load. b) The resistance of the primary and secondary windings. c) The transformer's full load operating efficiency as a percent.

8. A 10 power transformer supplies a load 8 kW of power at a power factor of 0.77 lagging at full load. The voltage at the load is 115V. The transformer has 1200 turns on its primary and 450 windings on its secondary. The iron loss is 325 Watts and the primary copper loss is 150 Watts and the secondary copper loss is 260 Watts. Find a) The full load apparent power and the secondary and primary currents at full load. b) The resistance of the primary and secondary windings. c) The transformer's full load operating efficiency as a percent.

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 3.28MCQ

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