In 3ϕ power measurement for a balanced load using the two-wattmeter method, the reactive power is given by:
1
the sum of both the wattmeter readings
2
√2 times the difference of the readings of the two wattmeters
3
√3 times the sum of the readings of the two wattmeters
4
√3 times the difference of the readings of the two wattmeters