Electrical
Load Current Calculator
Calculate electrical current from power, voltage, power factor and efficiency.
Use this calculator for quick electrical load checks for single-phase and three-phase systems. Suitable for preliminary sizing of circuits, breakers and cable calculations.
Inputs
Result
Load Current
-
Enter values and click calculate.
Method
Single-phase current is calculated from:
I = P ÷ (V × PF × η)
Three-phase current is calculated from:
I = P ÷ (√3 × V × PF × η)
- P = power (W)
- V = voltage (V)
- PF = power factor
- η = efficiency
- Calculated current = -
Reference
- This calculator applies standard electrical relationships between power, voltage and current.
- Three-phase calculations assume balanced load conditions.
- Typical UK nominal voltages: 230V (single-phase), 400V (three-phase).
- Relevant standards may include BS 7671 and associated electrical design guidance.
Design note: This calculator provides indicative results only.
Final design should consider diversity, starting currents, cable sizing, protection devices and installation method.