The current coil of a wattmeter is connected in the red line of a three-phase system. The voltage circuit can be connected between the red line and either the yellow line or the blue line by means of a two-way switch. Assuming the load to be balanced, show with the aid of a phasor diagram that the sum of the wattmeter indications obtained with the voltage circuit connected to the yellow and the blue lines respectively gives the total active power.

The current coil of a wattmeter is connected in the red line of a three-phase system. The voltage circuit can be connected between the red line and either the yellow line or the blue line by means of a two-way switch. Assuming the load to be balanced, show with the aid of a phasor diagram that the sum of the wattmeter indications obtained with the voltage circuit connected to the yellow and the blue lines respectively gives the total active power.

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

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.23P: A single-phase source has a terminal voltage V=1200volts and a currentI=1530, which leaves the...

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