Motor Capacity Solver

Amps to Horsepower Calculator (Amps to HP)

Determining unknown motor rating from nameplate voltage and clamp meter amperage. Reverse calculation estimating motor mechanical output power from measured clamp meter running current.

⚡ Amps to Horsepower Calculator (Amps to HP)

Measured Current (Amps)

Amps

Motor Voltage (V)

Volts

Motor Phase (1 or 3)

Phase

Calculated Result

Instant Calculation

Engineering Output

Auxiliary Output

Step-by-Step Derivation ▼ Show Steps

Governing Formula Verified Physics

1-Phase: HP = (I × V × η × PF) / 746 | 3-Phase: HP = (√3 × I × V × η × PF) / 746

Calculations adhere to standard electrical engineering physics and National Electrical Code (NFPA 70) regulations.

Engineering Principles & Calculations

This calculator uses the exact mathematical relationships between Current (Amps), Voltage (V), Phase (1Φ / 3Φ), Motor Efficiency (η), Power Factor (PF) to determine Output Horsepower (HP), Output Power (Kilowatts). In practical installations, factors such as ambient raceway temperature, harmonic distortion, duty cycle continuous operation, and conductor impedance must be accounted for by a certified electrician.

Reverse calculation estimating motor mechanical output power from measured clamp meter running current.

Typical Application & Industry Guidelines

Determining unknown motor rating from nameplate voltage and clamp meter amperage.

Reference Matrix