1. What is the Horsepower Formula for Electric Motors?

Definition: This calculator estimates the horsepower output of an electric motor based on voltage, current, efficiency, and power factor.

Purpose: It helps engineers, electricians, and technicians determine the mechanical power output of electric motors.

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 formula calculates electrical power (V×I), adjusts for real power (×PF) and efficiency (×η), then converts watts to horsepower (/746).

3. Importance of Horsepower Calculation

Details: Accurate horsepower calculation ensures proper motor sizing, energy efficiency, and system compatibility in electrical applications.

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 the 746 conversion factor?
A: 1 horsepower equals 746 watts, so we divide by 746 to convert electrical power to mechanical horsepower.

Q2: What's a typical motor efficiency value?
A: Standard motors range from 0.85-0.95 efficiency, with premium motors reaching 0.95+.

Q3: What affects power factor in motors?
A: Power factor depends on motor design and load, typically 0.8-0.9 for induction motors at full load.

Q4: How do I measure current accurately?
A: Use a clamp meter on one phase of a running motor under normal load conditions.

Q5: Can this be used for three-phase motors?
A: For three-phase, multiply voltage by √3 (1.732) before using this calculator.