Single phase kVA to Amps calculation formula
I(A) = 1000 × S(kVA) / V(V)
The current I in amps (A) is equal to 1000, multiplied by the apparent power S in kilovolt-amps (kVA), divided by the voltage V in volts (V).
So,
A = 1000 x kVA / V
amps = 1000 x kilovat-amps / volts
For example:
Power (S) = 2.5kVA
Voltage (V) = 110V
Phase current (I) = 1000 x 2.5kVA / 110V = 22,73A
Three phase kVA to Amps calculation formula
Line to line voltage
I(A) = 1000 × S(kVA) / (√3 × VL-L(V))
The phase current I in amps (with balanced loads) is equal to 1000, multiplied by the apparent power S in kilovolt-amps (kVA), divided by the square root of 3, multiplied by the line to line RMS voltage VL-L in volts (V).
So,
A = 1000 x kVA / (√3 x V)
amps = 1000 x kilovolt-amps / (√3 x volts)
For example:
Power (S) = 2.5kVA
Voltage (V) = 110V
Phase current (I) = 1000 x 2.5kVA / (√3 x 110V) = 13,12A
Line to neutral voltage
I(A) = 1000 × S(kVA) / (3 × VL-N(V))
The phase current I in amps (with balanced loads) is equal to 1000, multiplied by the apparent power S in kilovolt-amps (kVA), divided by 3, multiplied by the line to neutral RMS voltage VL-N in volts (V).
So,
A = 1000 x kVA / (3 x V)
amps = 1000 x kilovolt-amps / (3 x volts)
For example:
Power (S) = 2.5kVA
Voltage (V) = 110V
Phase current (I) = 1000 x 2.5kVA / (3 x 110V) = 7,576A