DC watts to amps calculation formula
I(A) = P(W) / V(V)
The current I in amps (A) is equal to the power P in watts (W), divided by the voltage V in volts (V).
So,
A = W / V
amp = watt / volt
For example:
Power (P) = 220W
Voltage (V) = 110V
Phase current (I) = 220W / 110V = 2A
AC single phase watts to amps calculation formula
I(A) = P(W) / (PF × V(V))
The phase current I in amps (A) is equal to the power P in watts (W), divided by the power factor PF, multiplied by the RMS voltage V in volts (V).
So,
A = W / (PF x V)
amp = watt / (PF x volt)
For example:
Power (P) = 220W
Voltage (V) = 110V
PF = 0,7
Phase current (I) = 220W / (0,7 x 110V) = 2,86A
AC three phase watts to amps calculation formula
Line to line voltage
I(A) = P(W) / (√3 × PF × VL-L(V))
The phase current I in amps (A) is equal to the power P in watts (W), divided by square root of 3, multiplied by the power factor PF, multiplied by the line to line RMS voltage VVL-L in volts (V).
So,
A = W / (√3 × PF x V)
amp = watt / (√3 × PF x volt)
For example:
Power (P) = 220W
Voltage (V) = 110V
PF = 0,7
Phase current (I) = 220W / (√3 × 0,7 x 110V) = 1,65A
Line to neutral voltage
I(A) = P(W) / (3 × PF × VL-N(V))
The phase current I in amps (A) is equal to the power P in watts (W), divided by 3, multiplied by the power factor PF, multiplied by the line to neutral RMS voltage VVL-N in volts (V).
So,
A = W / (3 × PF x V)
amp = watt / (3 × PF x volt)
For example:
Power (P) = 220W
Voltage (V) = 110V
PF = 0,7
Phase current (I) = 220W / (3 × 0,7 x 110V) = 0,95A