I have been trying to understand how to calculate real power and power factor in an AC circuit when given only circuit voltage and real/true current as measured by a current transformer (CT).(adsbygoogle = window.adsbygoogle || []).push({});

What I (think I) know:

1. Real power P = I^2 * R (but I don't know the circuit resistance)

2. Real power = apparent power * power factor

3. Apparent power S = RMS source voltage * RMS current

I believe I can take (source voltage ) / √2 to get the RMS of the voltage then (measured amperage) / √2 to get the RMS of the amperage and can then calculate the apparent power as the product of those two values but I don't know how to get to real power and power factor from there.

Thanks for any direction you can give me!

Phil

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# Calculating real power and power factor

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