A 3-ph, 3-wire balanced load with a lagging power factor is supplied at 400 V between lines. A single-phase wattmeter when connected with its current coil in the A-line and potential coil between A and B lines gives a reading of 6 kW. When the same terminal of the voltage coil are switched over to B- and C- lines, the current coil connections remaining the same, the reading of the wattmeter remains unchanged. Calculate the line current and the pf of the load.

A 3-ph, 3-wire balanced load with a lagging power factor is supplied at 400 V between lines. A single-phase wattmeter when connected with its current coil in the A-line and potential coil between A and B lines gives a reading of 6 kW. When the same terminal of the voltage coil are switched over to B- and C- lines, the current coil connections remaining the same, the reading of the wattmeter remains unchanged. Calculate the line current and the pf of the load.

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter7: Alternating Current, Power Distribution, And Voltage Systems

Section: Chapter Questions

Problem 8RQ

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