Merits of two wattmeter method

Merits of two wattmeter method
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Answer :

Merits of two wattmeter method: 1. This method can be used for balanced as well as unbalanced loads. 2. Connections of wattmeters are independent of load connection. 3. For balanced loads PF can also be determined. 4. Only two wattmeters are required for power measurement which reduces cost. 5. Reactive power can also be measured for balanced loads. 

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Answer :

Advantages of Two Wattmeter Method for 3-Phase Power Measurement:

1) It is used for balanced as well as unbalanced load.

2) For the star type load, it is not necessary to connect the neutral point for connection of wattmeter.

3) Delta load need not to be opened to connect the wattmeter.

4) For balanced loads, it possible to measure power factor along with the power.

5) Only two watt meters are required which reduces cost of instruments

6) It is possible to measure reactive volt-amperes for balanced loads also.

7) The circuit connections are independent of load connection.

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