Amperes to Horsepower Calculator
Convert electrical current (A) to mechanical horsepower (HP) for single- and three-phase systems using voltage, power factor, and efficiency with clear formulas...
amperes to horsepower calculator
The calculation of horsepower (ampere) requires that you consider voltage, power factor, efficiency, and whether the system is single-phase or three-phase. This equation is the input current divided by the real power (watts) multiplied by 100,000, which is divided by horsepower (HP). In three-phase systems, line-to-line voltage and the square root of three factor are added. This provides the correct calculations on the real-life electrical loads.
Formula & Table Summary:
Single-Phase: HP = (V × I × PF × η) / 746
Three-Phase: HP = (√3 × V × I × PF × η) / 746
Inverse: I = (HP × 746) / (V × PF × η)
amps to horsepower motor calculator
The Amperes to Horsepower Calculator is used to convert the electrical current (A) into the mechanical horsepower (HP) of motors and machines. It can be used in single-phase and three-phase systems, taking into account the voltage, the power factor, and efficiency. The fact that 1 horsepower = 746 watts makes it easy to determine the relation between electrical input and mechanical output with the help of this tool. It can be used by engineers, electricians, and students in rapid motor sizing, estimation of loads, and checking of power requirements. You can use this calculator to determine the HP of amps or amps of HP with a few inputs, giving accurate results.
amps to hp with pf and efficiency
| Current (A) | Voltage (V) | PF | Efficiency | Horsepower (HP) |
|---|---|---|---|---|
| 10 | 230 | 0.9 | 90% | 2.5 |
| 20 | 400 (3φ) | 0.85 | 92% | 10.2 |
| 50 | 460 (3φ) | 0.9 | 95% | 34.2 |
Frequently Asked Questions - Amperes to Horsepower Calculator:
How do I convert amps to horsepower?
Use HP=(electrical input×efficiency/1000)×1.34102; electrical input = V×I×PF (1φ) or √3×V_L×I_L×PF (3φ).
What power factor and efficiency should I use?
If unknown use conservative PF≈0.85–0.95 and efficiency η≈0.85–0.95 depending on motor size and load.
How many watts is 1 HP?
1 horsepower ≈ 746 watts; 1 kW ≈ 1.34102 HP.
Can I convert amps to HP without PF and efficiency?
You can, but results will be optimistic; set PF=1 and η=1 gives electrical HP, not mechanical output.
Formula for three-phase conversion?
HP = (√3×V_L×I_L×PF×η/1000)×1.34102.
How to find required amps for a given HP?
I = HP×1000/(1.34102×V×PF×η) for single-phase; divide by √3 for three-phase factor accordingly.
Does voltage affect HP for given amps?
Yes — higher voltage with same current yields more electrical power, so more available HP after accounting PF and efficiency.
Are these formulas for motor nameplate ratings?
They estimate mechanical output from electrical input; use nameplate data and safety margins for exact motor selection.
How accurate is this conversion?
Accuracy depends on using realistic PF and efficiency values; measure or use motor data for best results.
Can I use this for generators and inverters?
Yes — same electrical → mechanical power relations apply, but consider device-specific efficiencies and power quality effects.
