1. What is Electric Motor Horsepower?

Horsepower (HP) is a unit of measurement for power, representing the rate at which work is done. For electric motors, it indicates the mechanical output power based on electrical input parameters.

2. How Does the Calculator Work?

The calculator uses the horsepower formula:

Where:

• \( V \) — Voltage (volts)
• \( I \) — Current (amps)
• \( PF \) — Power factor (unitless, 0-1)
• \( \eta \) — Efficiency (decimal, 0-1)
• 746 — Conversion factor from watts to horsepower

Explanation: The formula calculates the mechanical power output by accounting for electrical input power (V×I) and adjusting for power factor and motor efficiency.

3. Importance of Horsepower Calculation

Details: Accurate horsepower calculation helps in selecting the right motor for an application, determining electrical requirements, and assessing motor performance.

4. Using the Calculator

Tips: Enter voltage in volts, current in amps, power factor (typically 0.8-0.95), and efficiency (typically 0.85-0.95 for most motors). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between input and output horsepower?
A: Input HP is the electrical power consumed, while output HP is the mechanical power delivered. This calculator determines output HP by accounting for efficiency.

Q2: Why is power factor important?
A: Power factor represents the phase difference between voltage and current in AC systems. A lower PF means more current is required for the same real power.

Q3: What's a typical efficiency for electric motors?
A: Standard efficiency ranges from 85% to 95% for most industrial motors, with higher efficiency motors reaching up to 97%.

Q4: Can I use this for three-phase motors?
A: Yes, but you'll need to multiply by √3 (1.732) for three-phase power calculations.

Q5: How does this relate to motor sizing?
A: The calculated HP should match or exceed the required mechanical load, with some safety margin for starting torque and variable loads.