three phase energy meter having a meter constant of 0.12rev/kWh is used with a potential transformer of ratio 22000/110V and a current transformer of ratio 500/5 amperes. When connected to a load of unity power factor , the disc makes 40 revolutions in 61 seconds. If the instrument readings are 110V and 5.25A, find the percentage error.

three phase energy meter having a meter constant of 0.12rev/kWh is used with a potential transformer of ratio 22000/110V and a current transformer of ratio 500/5 amperes. When connected to a load of unity power factor , the disc makes 40 revolutions in 61 seconds. If the instrument readings are 110V and 5.25A, find the percentage error.

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 3.57P: A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when...

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