Convert current (amps) to real power (kW) and apparent power (kVA) for single- and three-phase circuits.
Convert current (amps) to real power (kW) for single- and three-phase circuits, with apparent power (kVA) shown.
Real power is found from kW = (V × I × PF) / 1000 for single-phase, or kW = (√3 × V × I × PF) / 1000 for three-phase. The calculator also shows apparent power (kVA), which is the same figure before power factor is applied. For resistive loads (power factor 1.0) kW and kVA are equal; for motors the kVA is higher.
This is useful for checking the real demand of a circuit against its protective device — for example, a 32A single-phase circuit at 230V can carry up to 7.36kW at unity power factor.
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