Three Phase Current – Calculation
Use this guide to size the right generator for your needs
The power taken by a circuit (single or three-phase) is measured in watts W (or kW). The product of the voltage and current is the apparent power, measured in VA (or kVA). The relationship between kVA and kW is the Power Factor (PF):
kW = kVA × PF (or) kVA = kW / PFCalculate the Right 3-Phase Generator Size
Calculations assume 380V / 60Hz three-phase power, matching our full product range.
Enter your total load to see the result
This tool provides an estimate for guidance only. Please contact our team to confirm the exact specification for your project.
Common Generator Sizes
Once you know your load, pick the right unit from the sizes most requested in Saudi Arabia — Kubota for small and medium loads, Cummins and John Deere for larger ones:
For kVA-to-amps tables, diesel consumption per model, and how many air conditioners each generator runs, see the generator sizing guide.
Need Help Sizing Your Generator?
Our team can help you calculate the right generator size for your specific needs. Contact us for a free consultation.
Contact UsSingle Phase System
Given the kW and power factor, the kVA can be worked out directly. The current is the kVA divided by the voltage.
Three Phase System
In a three-phase system, convert to single-phase by dividing total kW by 3, then follow the single-phase method.
Three-Phase Current Formula
Frequently Asked Questions
How do I calculate the kVA needed for my generator?
Divide the total watt load by the power factor (typically 0.8 for diesel generators), then divide by 1000 to get kVA. Multiply by 1.25 to operate at 80% prime power capacity.
What is the difference between prime power and standby power in a generator?
Prime power is the continuous maximum power available at variable load for unlimited hours. Standby power is the maximum power available during a utility outage — typically 10% higher than prime, not for continuous use.
What is the formula for three-phase current calculation?
I = P / (√3 × V × PF), where P is power in watts, V is line voltage (380V in Saudi Arabia), and PF is the power factor.
