1. What is Electric Motor Power?

Electric motor power is the rate at which electrical energy is converted to mechanical energy. It's typically measured in watts (W) or horsepower (HP). The power depends on voltage, current, and power factor of the motor.

2. How Does the Calculator Work?

The calculator uses the single-phase AC power formula:

Where:

• \( P \) — Power in watts (W)
• \( V \) — Voltage in volts (V)
• \( I \) — Current in amperes (A)
• \( PF \) — Power factor (unitless, 0-1)

Explanation: For three-phase systems, the formula would include a √3 factor (1.732). The power factor accounts for the phase difference between voltage and current.

3. Importance of Power Calculation

Details: Calculating motor power helps in proper motor selection, energy efficiency assessment, and electrical system design. It's essential for sizing circuit breakers, wires, and other components.

4. Using the Calculator

Tips:

• Measure voltage with a multimeter at motor terminals
• Measure current with a clamp meter
• Typical power factor for motors ranges from 0.8-0.95
• For three-phase systems, multiply result by √3 (1.732)

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between real power and apparent power?
A: Real power (P, in watts) is the actual usable power, while apparent power (S, in VA) is the product of voltage and current. The ratio is the power factor (PF = P/S).

Q2: How does motor efficiency affect power calculation?
A: Efficiency accounts for losses (heat, friction). Mechanical power output = Electrical power input × Efficiency.

Q3: What is a typical power factor for electric motors?
A: Usually 0.8-0.95 for healthy motors. Lower values may indicate problems or light loading.

Q4: How do I calculate three-phase motor power?
A: For three-phase: \( P = V \times I \times PF \times \sqrt{3} \). Our calculator gives single-phase power.

Q5: Can I calculate current if I know power and voltage?
A: Yes, rearrange the formula: \( I = P / (V \times PF) \).