Illustrate how can you use a single-phase wattmeter to measure 3 phase reactive power in a circuit?

Illustrate how can you use a single-phase wattmeter to measure 3 phase reactive power in a circuit?
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1 Answer

Answer :

We can measure reactive power of 3 phase circuit by dingle phase wattmeter by connecting the current coil in series with a line or load and connecting the pressure coil across the other two lines. 

Reactive power = 3√ V * I * sinϕ Watts. 
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