Convert a current reading into kVA, kW and horsepower for single-phase or three-phase supplies.
Tell us what you need to power and we will confirm the exact model, voltage and configuration — usually within 24 hours.
If you can measure current but not power, this is the conversion you need. For three-phase supplies the formula is kVA = √3 × A × V ÷ 1000. For single-phase it is kVA = A × V ÷ 1000. Multiply by the power factor to get kW.
Getting this wrong is the most common source of a result that is out by a factor of √3.
In a balanced three-phase system the three phase currents are 120° apart, so they do not simply add. The √3 factor accounts for that geometry. For an unbalanced system, calculate each phase separately and take the highest.
Yes, but use the kVA figure rather than kW, and add margin for motor starting current. A changeover switch must handle the surge, not just the running current.
