1. What is Motor Horsepower Calculator?

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

Purpose: It helps engineers and technicians determine the power output of electric motors for proper sizing and selection.

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)

Explanation: The product of voltage and current gives apparent power, which is then adjusted by efficiency and power factor to get real power, then converted to horsepower.

3. Importance of Horsepower Calculation

Details: Proper horsepower estimation ensures motors are correctly sized for their loads, preventing underpowering or wasteful overpowering.

4. Using the Calculator

Tips: Enter the voltage in volts, current in amps, 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: Why divide by 746 in the formula?
A: 1 horsepower equals 746 watts, so we convert from watts to HP.

Q2: What's a typical motor efficiency?
A: Standard motors range from 80-95% efficiency (0.8-0.95), with premium motors being more efficient.

Q3: What affects power factor?
A: Load conditions, motor design, and power quality all influence power factor.

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

Q5: How accurate is this calculation?
A: It provides theoretical maximum; actual HP may vary due to operating conditions and motor age.