1. What is Electrical Horsepower?

Electrical horsepower is a unit of measurement for the power output of electric motors and other electrical machinery. It represents the rate at which work is done, with 1 HP equal to 746 watts.

2. How Does the Calculator Work?

The calculator uses the electrical horsepower formula:

Where:

• \( V \) — Voltage (volts)
• \( I \) — Current (amps)
• \( EFF \) — Motor efficiency (decimal, 0-1)
• \( PF \) — Power factor (decimal, 0-1)
• 746 — Conversion factor from watts to HP

Explanation: The formula accounts for both the electrical power (V × I) and the efficiency of conversion to mechanical power (EFF × PF).

3. Importance of Electrical HP Calculation

Details: Calculating electrical horsepower is essential for motor sizing, energy efficiency analysis, electrical system design, and comparing motor performance.

4. Using the Calculator

Tips:

• Measure voltage and current under normal operating conditions
• Typical efficiency for electric motors ranges from 70-95% (0.7-0.95)
• Power factor typically ranges from 0.8-1.0 for AC motors
• For three-phase systems, multiply by √3 (1.732) for line-to-line voltage

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between mechanical and electrical HP?
A: Electrical HP accounts for conversion losses (efficiency and power factor) while mechanical HP measures actual output power.

Q2: Why is 746 watts equal to 1 HP?
A: This conversion factor was established by James Watt when comparing steam engine output to draft horse power.

Q3: How does three-phase power affect the calculation?
A: For three-phase systems, multiply voltage by √3 (1.732) before using in the formula.

Q4: What's a typical power factor for motors?
A: Most AC induction motors have power factors between 0.8-0.95 when fully loaded.

Q5: How accurate is this calculation?
A: It provides a good estimate but actual performance may vary based on operating conditions and motor design.