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power calculator

Enter values to get the other values and press the Calculate button:

AC single phase watts to amps calculation formula

The phase current I in amps (A) is equal to the real power P in watts (W), divided by the power factor PF times the RMS voltage V in volts (V):

I(A) = P(W) / (PF × V(V) )

So amps are equal to watts divided by power factor times volts.

amps = watts / (PF × volts)


A = W / (PF × V)


What is the phase current in amps when the power consumption is 330 watts, the power factor is 0.8 and the RMS voltage supply is 110 volts?

I = 330W / (0.8 × 110V) = 3.75A

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