. 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.

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 3.43P: Three single-phase transformers, each rated 10MVA,66.4/12.5kV,60Hz, with an equivalent series...

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