1. What is the Horsepower Formula?

The horsepower formula calculates the mechanical power output of an electric motor based on its electrical input characteristics. It accounts for voltage, current, power factor, and motor efficiency.

2. How Does the Calculator Work?

The calculator uses the horsepower formula:

Where:

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

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

3. Importance of Motor HP Calculation

Details: Accurate horsepower calculation is essential for selecting the right motor for an application, ensuring proper performance, and avoiding overloading.

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 is power factor?
A: Power factor is the ratio of real power to apparent power, representing how effectively current is being converted into useful work.

Q2: What's a typical efficiency for electric motors?
A: Standard efficiency ranges from 85% to 95% for most industrial motors, with premium efficiency motors reaching 95% or higher.

Q3: Why divide by 746?
A: 746 watts equals 1 horsepower, so this converts the electrical power calculation to mechanical horsepower.

Q4: Can I use this for three-phase motors?
A: For three-phase motors, you need to multiply by √3 (approximately 1.732) to account for the three phases.

Q5: How does motor size affect efficiency?
A: Larger motors generally have higher efficiency than smaller ones. Efficiency typically increases with motor size.