Amps to kW conversions formulas are used to compute kilowatts from the known voltage and current in circuits. Given below are 4 different formulas for the conversion:

  • Single phase DC: kW = (E * I)/1000
  • Single phase AC: kW = (E * I * PF)/1000
  • Two-phase, Four wire AC: kW = (2 * E * I * PF)/1000
  • Three phase AC: kW = (1.73 * E * I * PF)/1000

kW = Power (kilowatt); E = Voltage (volts); I = Current (Amps)

Let’s solve some example problems for better understanding the formulae.


Single Phase DC

A 100 volt DC motor draws a current of 20 Amps. Find the power.

Solution: kW = (100 * 20) / 1000 = 2 kW


Single Phase AC

A 120-volt single phase AC motor draws a current of 15 Amps at a power factor 88%. Determine the power in kilowatts.

Solution: kW = (120 * 15 * 0.88) / 1000 = 1.5 kW


Three phase AC

A 230-volt three-phase AC motor draws a current of 20 Amps at a power factor of 95%. Determine the power in kilowatts.

Solution: kW = (1.73 * 230 * 20 * 0.95) / 1000

= 7.56 kW