1. What is an Electric Motor Horsepower Calculator?

Definition: This calculator estimates the mechanical horsepower output of an electric motor based on its electrical input characteristics.

Purpose: It helps engineers, technicians, and electricians determine the power output of motors for proper sizing and performance evaluation.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The formula converts electrical power (adjusted for efficiency and power factor) to mechanical horsepower.

3. Importance of Horsepower Calculation

Details: Accurate horsepower calculation ensures proper motor selection, prevents overload conditions, and helps evaluate motor performance.

4. Using the Calculator

Tips: Enter voltage in volts, current in amps, efficiency (default 0.9), and power factor (default 0.85). 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 0.8-0.95 for good quality 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, so we convert electrical watts to mechanical horsepower.

Q4: Can I use this for 3-phase motors?
A: This formula works for single-phase. For 3-phase, multiply by √3 (1.732).

Q5: How do I find motor current?
A: Measure with a clamp meter or check motor nameplate specifications.