Wiring - What is VA Volt-Amps and KVA Kilovolt-Ampere and How to Calculate It
KVA (kilovolt-ampere) and VA (volt-amps) are both a measurement of power consumed by an electrical circuit. It is important to note that the calculations differ between single and three phase power so you must know which one you have.
Single phase equation.
- VA = Volts X Amps
- KVA = Volts X Amps / 1000
Three phase equation. For three phase, you take the square root of 3 (√3) or 1.732 multiplied by the line to line voltage multiplied by the amps.
- VA = √3 X Volts X Amps
- KVA = √3 X Volts X Amps / 1000
Single Phase. What is the VA of a 120VAC single phase load that pulls 12 amps?
- Volts = 120
- Amps = 12
- KVA = Volts X Amps = 120 X 12 = 2400VA
Three phase. What is the KVA of a 480VAC three phase load that pulls 86 amps?
- Volts Line to Line = 480
- Amps = 86
- KVA = √3 X Volts X Amps / 1000 = 1.732 X 480 x 86 / 1000 = 71.5KVA
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