1. What is an Electric Motor Horsepower Calculator?

Definition: This calculator determines the mechanical horsepower output of an electric motor based on electrical input parameters.

Purpose: It helps engineers, technicians, and electricians evaluate motor performance and select appropriate motors for applications.

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 HP)

Explanation: The electrical power (V×I) is adjusted by efficiency and power factor to get mechanical power, then converted to horsepower.

3. Importance of Horsepower Calculation

Details: Accurate horsepower calculation ensures proper motor sizing, prevents overload conditions, and optimizes energy efficiency.

4. Using the Calculator

Tips: Enter voltage (V), current (A), efficiency (default 0.85), and power factor (default 0.9). Efficiency and power factor must be between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is motor efficiency?
A: The ratio of mechanical power output to electrical power input, typically 0.7-0.95 for industrial motors.

Q2: What is power factor?
A: The ratio of real power to apparent power, representing phase difference between voltage and current (typically 0.8-0.95).

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

Q4: Can I use this for three-phase motors?
A: No, this is for single-phase. Three-phase requires multiplying by √3 (1.732).

Q5: How do I measure motor current?
A: Use a clamp meter on one power lead while motor runs under load.