2 Answers

Answer :

The power factor of a single phase load can be calculated if the instruments available are one voltmeter, one ammeter and one wattmeter.

Answer :

The power factor of a single phase load can be calculated if the instruments available are three ammeters or three voltmeters.


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Last Answer : The two pressure coils of a single phase power factor meter have the same dimensions and the same number of turns.

Description : What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016 revolutions and the meter constant in revolution is 420? A) 0.04 B) 1.04 C) 0.96 D) None of these

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Last Answer : 0

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Last Answer : Power station having Load factor = 70%, capacity factor = 50%, used factor = 60%, maximum demand = 20MW then annual energy production is 122.8 GWh

Description : In a synchronous generator delivering lagging power factor load  (1) the excitation emf leads terminal voltage by the power angle (2) the excitation emf lags terminal voltage by the power angle (3) ... by the power factor angle (4) excitation emf lags the terminal voltage by the power factor angle

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Last Answer : Minimum voltage regulation occurs when the power factor of the load is leading.

Description : If the load of the normally excited synchronous motor is increased the power factor will?

Last Answer : If the load of the normally excited synchronous motor is increased the power factor will become lagging.

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Description : With a neat sketch explain working of 1 phase dynamometer type power factor meter.

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Description : In an alternator at lagging power factor the generated voltage per phase as compared to that at unity power factor?

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Last Answer : Induction type single phase energy meters measure electric energy in kWh.

Last Answer : Commonly used instruments in power system measurement are induction.

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Last Answer : Circuit Diagram: Waveforms:

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Description : The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is 220 V. With the potential coil connected on the load side, the meter indicates 100 W. Approximate percentage error due to wattmeter connection is (A) 11% (B) 9% (C) 1.1% (D) 3%

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Last Answer : Single phase Transformer Transformer

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Last Answer : single phase full converter

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