Two-wattmeter method is used to measure the power taken by a 3-phase induction motor on no load. The wattmeter readings are 400 W and -50 W. Calculate the reactive power taken by the load

• A. 350/√3 VAR
• B. 450√3 VAR
• C. 450/√3 VAR
• D. 350√3 VAR

Answer: (B)

Reactive power taken (Q) = √3*(W1 - W2)
= √3*(450 + 50)
= √3*450 kVAR