Three-Phase Power Calculator (kW, kVA, PF)
Calculate three-phase apparent power (kVA) and real power (kW/W) using √3 × V × I, with optional power factor for HVAC commercial service work.
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Frequently asked questions
What is the three-phase power formula?
Apparent power for three-phase systems is kVA = (√3 × V × I) ÷ 1000 using line-to-line voltage (V) and line current (I). Real power is kW = kVA × PF.
What is power factor (PF)?
Power factor (PF) represents how effectively current is converted into real work. PF ranges from 0 to 1. Motors and compressors often have PF less than 1, so real kW is lower than apparent kVA.
Which voltage should I enter: line-to-line or line-to-neutral?
Enter line-to-line voltage for this calculator (common values include 208V, 240V, 480V).
When is this useful for HVAC work?
Use it to sanity-check electrical load on commercial HVAC equipment like RTUs, VRF outdoor units, and large motors by converting measured volts and amps into kVA/kW.
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