3-Phase Motor Amperage Calculator
Free calculate the current draw and amperage for 3-phase ac motors based on horsepower, voltage, efficiency, and power factor.
Motor Parameters
Common: 208V, 230V, 460V, 480V
Typical: 85-95% for modern motors
Typical: 0.80-0.90 for induction motors
Results
Enter motor parameters to calculate amperage
3-Phase Motor Calculation Guide
Formula
I = (HP × 746) / (√3 × V × η × PF)
Where:
- • HP = Horsepower
- • V = Voltage (line-to-line)
- • η = Efficiency (decimal)
- • PF = Power Factor
Common Motor Sizes
- • 1 HP: ~1.5-2.5 amps
- • 5 HP: ~7-10 amps
- • 10 HP: ~14-18 amps
- • 50 HP: ~65-75 amps