Wattmeter Multiple Choice Questions and Answers

11. In a low power factor wattmeter the compensating coil is connected

   A.In series with current coil

   B.In parallel with current coil

   C.In series with pressure coil

   D.In parallel with pressure coil

12. In a 3-phase power measurement by two wattmeter method, both the wattmeters had identical readings. The power factor of the load was

   A.Unity

   B.0.8 lagging

   C.0.8 leading

   D.Zero

13. In a 3-phase power measurement by two wattmeter method the reading of one of the wattmeter was zero. The power factor of the load must be

   A.Unity

   B.0.5

   C.0.3

   D.Zero

14. Wattmeter cannot be designed on the principle of

   A.Electrostatic instrument

   B.Thermocouple instrument

   C.Moving iron instrument

   D.Electrodynamic instrument

15. The readings of a dynamometer type wattmeter can be highly erratic at

   A.Low frequencies

   B.Fluctuating loads

   C.Low power factors

   D.High voltages

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