1. What is Electric Motor Power?

Electric motor power is the rate at which the motor can do work, typically measured in watts or horsepower. It's calculated using voltage, current, and power factor for AC motors.

2. How Does the Calculator Work?

The calculator uses the power formula:

For three-phase systems, the formula becomes:

Where:

• \( P \) — Power in watts
• \( V \) — Voltage in volts
• \( I \) — Current in amps
• \( PF \) — Power factor (unitless, between 0 and 1)

Explanation: The power factor accounts for the phase difference between voltage and current in AC circuits. A higher power factor indicates more efficient power transfer.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for sizing motors, determining electrical load, calculating energy consumption, and ensuring proper circuit protection.

4. Using the Calculator

Tips: Enter voltage in volts, current in amps, and power factor (typically 0.8-0.95 for motors). Select single or three phase system. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical power factor for motors?
A: Induction motors typically have power factors between 0.8 and 0.9 when fully loaded, dropping to 0.2-0.3 at no load.

Q2: How does three-phase power differ from single-phase?
A: Three-phase power provides more consistent power delivery and requires less conductor material for the same power transfer.

Q3: Why is power factor important?
A: Low power factor increases current for the same real power, leading to higher energy losses and requiring larger equipment.

Q4: Can I calculate horsepower from this?
A: Yes, 1 horsepower ≈ 746 watts. Divide the wattage result by 746 to get horsepower.

Q5: What about motor efficiency?
A: This calculator gives electrical input power. Mechanical output power would be input power multiplied by motor efficiency.