Electrical

kW → Amps

Calculate AC current from real power, voltage, phase, and power factor.

Select the electrical system configuration.
Enter real electrical power.
For three-phase systems, enter line-to-line voltage.
Enter a value between 0 and 1.

Calculated Current

Field Note: This calculation assumes a balanced AC system and uses real power in kW. For actual equipment selection, protection, and conductor sizing, verify the equipment nameplate and applicable electrical requirements.

kW to Amps Formula

The current required for a given real power depends on voltage, phase configuration, and power factor.

Three-Phase

I = (kW × 1000) ÷ (√3 × Voltage × Power Factor)

Single-Phase

I = (kW × 1000) ÷ (Voltage × Power Factor)

Example

A balanced 3-phase, 480 V system delivers 10 kW at a power factor of 0.90.

I = (10 × 1000) ÷ (√3 × 480 × 0.90)

Calculated current: ≈ 13.4 A

Electrical Troubleshooting

Measured current is higher than calculated

Check the actual power factor, voltage, load level, equipment condition, and whether the measured power represents the same operating condition as the calculation.

Power factor changes with load

Motors and other inductive loads can have a power factor that varies with operating load. Use the power factor corresponding to the operating condition being evaluated.

Three-phase currents are not balanced

Check phase voltage balance, connections, conductor condition, equipment loading, and the load itself. This calculator assumes a balanced system.

Common Mistakes

  • Forgetting the √3 factor for three-phase systems.
  • Using line-to-neutral voltage where line-to-line voltage is required for the three-phase formula.
  • Assuming power factor is 1.0 for every load.
  • Confusing kW with kVA.
  • Treating calculated current as equipment nameplate current.
  • Ignoring actual operating conditions when comparing the calculation with measured current.

Related Calculators

Engineering Note

Real power, apparent power, and current are related through power factor. A lower power factor requires more current to deliver the same real power at the same voltage.

This calculator assumes a balanced AC system and is intended for estimation and engineering reference. Verify actual equipment ratings, nameplate information, and applicable electrical requirements for installation and protection work.