1. What is Electric Motor Horsepower?

Definition: Horsepower (HP) is a unit of power that measures the rate at which work is done by an electric motor.

Purpose: This calculator helps determine the mechanical power output of an electric motor based on its electrical characteristics.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( HP \) — Horsepower output
• \( V \) — Voltage (volts)
• \( I \) — Current (amps)
• \( \eta \) — Motor efficiency (0-1)
• \( PF \) — Power factor (0-1)
• 746 — Conversion factor (watts to horsepower)

Explanation: The formula calculates the actual mechanical power output by accounting for electrical input and motor efficiency.

3. Importance of Motor Horsepower Calculation

Details: Proper horsepower calculation ensures proper motor sizing for applications, prevents overload conditions, and helps with energy efficiency planning.

4. Using the Calculator

Tips: Enter the motor voltage, current draw, efficiency (default 0.85), and power factor (default 0.9). Efficiency and power factor values must be between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is motor efficiency?
A: Efficiency (η) is the ratio of mechanical power output to electrical power input, typically 0.7-0.95 for electric motors.

Q2: What is power factor?
A: Power factor (PF) is the ratio of real power to apparent power, representing phase difference between voltage and current (typically 0.8-1.0).

Q3: Why divide by 746?
A: 746 watts equals 1 horsepower, so we convert electrical watts to mechanical horsepower.

Q4: How do I find motor current?
A: Measure with a clamp meter or check motor nameplate specifications.

Q5: Does this work for 3-phase motors?
A: For 3-phase motors, multiply voltage by √3 (1.732) before using this calculator.