Calculate apparent power (kVA), true power (kW), line current and power factor for balanced three-phase loads. Ideal for load planning, switchboard sizing and motor circuits.
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Enter voltage, current and power factor to calculate kVA, kW and reactive power.
Enter in watts
Common Loads:
Apparent power: kVA = √3 × V_line × I / 1000. True power: kW = kVA × power factor. In NZ and AU, line voltage is 400V (230V phase-to-neutral).
I = kVA × 1000 / (√3 × V_line). Example: 10 kVA at 400V = 10,000 / (1.732 × 400) = 14.4A per phase.
Use 400V line-to-line voltage for three-phase power calculations in NZ. The phase voltage (line-to-neutral) is 230V.
Power factor is the ratio of real power (kW) to apparent power (kVA). Motors and lighting loads typically have PF of 0.7–0.9. A low power factor means higher current for the same useful power, which affects cable and switchboard sizing.
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