Measurement of power and power factor of a 3-phase system by two wattmeter method can be

Measurement of power and power factor of a 3-phase system by two wattmeter method can be obtained in case of 

1. Balanced load and balanced source 

2. Balanced source with 3-phase 3-wire unbalanced load 

3. Unbalanced source with 3-phase 3-wire balanced load 

4. Balanced source with 3-phase 4-wire unbalanced load 

5. unbalanced and unbalanced source 

 

(a) 1 only (b) 2, 3 and 5 (c) 1, 2, 3, 4 and 5 (d) 1, 2, 3 and 5 
by

1 Answer

Answer :

Measurement of power and power factor of a 3-phase system by two wattmeter method can be obtained in case of 

1. Balanced load and balanced source 

2. Balanced source with 3-phase 3-wire unbalanced load 

3. Unbalanced source with 3-phase 3-wire balanced load 

4. Balanced source with 3-phase 4-wire unbalanced load 

5. unbalanced and unbalanced source 

 

(a) 1 only (b) 2, 3 and 5 (c) 1, 2, 3, 4 and 5 (d) 1, 2, 3 and 5 

by

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In the measurement of power of balanced load by two wattmeter method in a 3-phase circuit, The readings

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In a 3-phase power measurement by two wattmeter method the reading of one of the wattmeter was zero...

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Description : State any two disadvantages of one wattmeter method of measurement of 3 phase power.

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Explain the effect of power factor on wattmeter reading in two wattmeter method for power measurement.

Description : Explain the effect of power factor on wattmeter reading in two wattmeter method for power measurement.

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Last Answer : B

Consider the following statements 1) The compensating coil of a low power factor wattmeter compensates

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In a low power factor wattmeter the compensating coil is connected?

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In a low power factor wattmeter the pressure coil is connected?

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Draw and explain the circuit diagram for measurement of single phase power using dynamometer type wattmeter.

Description : Draw and explain the circuit diagram for measurement of single phase power using dynamometer type wattmeter. 

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Last Answer : Answer :

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A dynamometer wattmeter can be used for?

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The resistance in the circuit of the moving coil of a dynamometer wattmeter should be?

Last Answer : The resistance in the circuit of the moving coil of a dynamometer wattmeter should be high.

The instrument for measurement of flow/ velocity is________. A. Bimetallic. C) Turbine meter. B. Manometer. D) Wattmeter

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The true power indicated by a wattmeter depends on the current flow through the load, the magnitude of the potential across the load, and the _____________. A. power factor of the load B. angle of coil displacement C. inertia of the movable coil D. high resistance from the load

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Last Answer : Answer: A

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The true power indicated by the pointer movement of a wattmeter depends on the current flow through the load, the magnitude of the potential across the load, and the ____________. A. power factor of the load B. angle of coil displacement C. inertia of the movable coil D. high resistance from the load

Description : The true power indicated by the pointer movement of a wattmeter depends on the current flow through the load, the magnitude of the potential across the load, and the ____________. A. power factor of the ... B. angle of coil displacement C. inertia of the movable coil D. high resistance from the load

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Which of the listed meters uses a shunt connected in series with the load, but parallel with the meter movement? A. Voltmeter B. Power factor meter C. Ammeter D. Wattmeter

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A portable hand-held and is very handy for determining the power consumption and power factor of individual motors and other inductive devices. a) Voltmeter and wattmeter. b) Wattmeter and power factor meter. c) Light meter and flash meter.

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Last Answer : The power consumed by a balanced 3-ph load is measured by two-wattmeter method. The meter readings are 8 kW and 4 kW. The power factor of the load is between 0.5 and unity

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The function of measurement system is/are _____.

Description : The function of measurement system is/are _____.

Last Answer : The function of measurement system are indicating, recording and controlling function.

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Description : Can I use 3 phase wattmeter in the single phase supply?

Last Answer : The three-wire, three-wattmeter connection has the advantages of indicating the power in each individual phase (not possible in the two-wattmeter connection) and phase to neutral voltages. In a single-phase system there are just two

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