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Kilowatts to Amps Calculator

kW/W to Amps Calculator | Power to Current Conversion

kW/W to Amps (A) Calculator

Current in amps:

Calculation Formulas

DC power to amps calculation

I(A) = P(W) / V(V)
or
I(A) = 1000 × P(kW) / V(V)

Where:

  • I(A) is the current in amps
  • P(W) is the power in watts
  • P(kW) is the power in kilowatts (1 kW = 1000 W)
  • V(V) is the voltage in volts
  • PF is the power factor (AC circuits only, between 0 and 1)
  • VL-L(V) is the line to line voltage (three phase AC)
  • VL-N(V) is the line to neutral voltage (three phase AC)

How to Convert Power to Amps

To convert from power (watts or kilowatts) to amps (A), you need to know:

  1. Whether the circuit is DC, single phase AC, or three phase AC
  2. The voltage of the circuit
  3. For AC circuits, the power factor (between 0 and 1)
  4. For three phase circuits, whether the voltage measurement is line-to-line or line-to-neutral

Example Calculations

DC example

What is the current in amps when the power is 1.5 kW (1500 W) and the voltage supply is 120 volts?

Using watts: I = 1500W / 120V = 12.5A

Using kilowatts: I = 1000 × 1.5kW / 120V = 12.5A

Single phase AC example

What is the current in amps when the power is 2 kW (2000 W), the voltage supply is 120 volts, and the power factor is 0.8?

Using watts: I = 2000W / (0.8 × 120V) = 20.83A

Using kilowatts: I = 1000 × 2kW / (0.8 × 120V) = 20.83A

Three phase AC example (line to line voltage)

What is the current in amps when the power is 5 kW (5000 W), the voltage supply is 208 volts (line to line), the power factor is 0.8, and the connection is three phase?

Using watts: I = 5000W / (√3 × 0.8 × 208V) = 17.35A

Using kilowatts: I = 1000 × 5kW / (√3 × 0.8 × 208V) = 17.35A

Power to Amps Conversion Table

Power Unit Voltage (V) Current (A) Type PF
1.5 kW 120 12.50 DC –
1500 W 120 12.50 DC –
2 kW 120 20.83 Single AC 0.8
2000 W 120 20.83 Single AC 0.8
5 kW 208 17.35 Three AC (L-L) 0.8
5000 W 208 17.35 Three AC (L-L) 0.8
7.5 kW 240 22.56 Three AC (L-L) 0.8
7500 W 240 22.56 Three AC (L-L) 0.8

Understanding Power and Current

This calculator converts between electrical power (measured in watts or kilowatts) and current (measured in amps). The relationship between power and current depends on:

  • The type of circuit (DC, single phase AC, or three phase AC)
  • The voltage of the circuit
  • For AC circuits, the power factor which represents the phase difference between voltage and current

This tool is particularly useful for electrical engineers, technicians, and students working with electrical systems and need to determine current requirements based on power ratings.