Single phase amps to KVA calculation:
The apparent power, in kilovolt-amperes (KVA), is calculated by multiplying the voltage, in volts (V), by the current, in amperes (A), and dividing by 1000.
KVA = I x V/1000
3 phase amps to KVA calculation:
Calculation with Line to Line voltage:
Kilovolt-amps equals phase current I in amps times line-to-line RMS voltage VL-L in volts divided by 1000.
KVA = √3 × I × VL-L / 1000
Calculation with Line to Neutral voltage:
Kilovolt-amps equals phase current I in amps times line-to-neutral RMS voltage VL-N in volts divided by 1000.
KVA = 3 × I × VL-N / 1000
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