Horsepower to Amperes Calculator
Convert horsepower (HP) to motor current (Amps) using voltage, efficiency, and power factor. Supports single-phase and three-phase AC motors.
horsepower to amperes calculator
Current (A) = (HP *0.746* 1000)/(E3.sqrt(3) V PF eta) in 3phi motors. To 1 Philipper, add no square root of three to it. To obtain accurate results, efficiency and PF need to be taken into consideration.
Formula & Table Summary:
- P(kW) = HP × 0.746
- 1φ: I = (HP × 0.746 × 1000) / (V × PF × η)
- 3φ: I = (HP × 0.746 × 1000) / (√3 × V × PF × η)
3 phase hp to amps calculator
This horse power to Amperes Calculator allows you to estimate the current that a motor will draw based on its horsepower rating, its various voltages and its efficiency and its power factor. It can operate AC motors in three-phase and single phase. This can be handy when trying to size circuit breaker, cable, and transformer loads. It has many applications in industrial motors installations, in pump sizing, HVAC as well as electrical design work.
single phase hp to amps
| HP | Voltage (V) | Phase | PF | Eff (%) | Current (A) |
|---|---|---|---|---|---|
| 5 | 230 | 1φ | 0.9 | 90 | 19.4 |
| 10 | 415 | 3φ | 0.85 | 92 | 16.6 |
| 50 | 460 | 3φ | 0.9 | 95 | 85.0 |
Frequently Asked Questions - Horsepower to Amperes Calculator:
How do you convert horsepower to amps?
Use I = (HP × 0.746 × 1000) / (√3 × V × PF × η) for 3-phase or without √3 for single-phase.
What is 1 HP in amps?
At 230V, 1φ, PF=0.9, η=90%, 1 HP ≈ 3.6 A.
What is the conversion factor of HP to kW?
1 HP = 0.746 kW.
Does efficiency affect current?
Yes, lower efficiency means higher current for the same HP load.
Why do I need PF in HP to Amps conversion?
Power factor accounts for reactive power; poor PF increases current demand.
How many amps does a 10 HP 3-phase motor draw?
At 415V, PF=0.85, η=92%, current ≈ 16.6 A.
Is HP to amps the same for AC and DC motors?
No, AC uses PF and √3 for 3φ. DC uses I = (HP × 746)/(V × η).
What cable size should I use after HP to amp conversion?
Choose based on ampacity tables with a margin above calculated amps.
Why is voltage important in HP to amps?
Higher voltage reduces current for the same power, lowering cable size.
What tools use this conversion?
Used for pump motors, compressors, HVAC fans, conveyors, and industrial loads.
