1. What is the Motor Power Formula?

Definition: This formula calculates the actual power output of an electric motor based on its electrical characteristics and efficiency.

Purpose: It helps engineers and technicians determine the real power consumption and output of electric motors in various applications.

2. How Does the Formula Work?

The formula used is:

Where:

• \( P_w \) — Motor power output (watts)
• \( V \) — Voltage supplied to the motor (volts)
• \( I \) — Current drawn by the motor (amps)
• \( \eta \) — Motor efficiency factor (0-1)
• \( PF \) — Power factor (0-1)

Explanation: The formula accounts for both the electrical input (V × I) and the motor's efficiency characteristics (η × PF).

3. Importance of Motor Power Calculation

Details: Accurate power calculation ensures proper motor sizing, energy efficiency assessment, and electrical system design.

4. Using the Calculator

Tips: Enter the voltage, current, efficiency (default 0.9), and power factor (default 0.8). Efficiency and power factor must be between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is motor efficiency?
A: Efficiency (η) is the ratio of mechanical power output to electrical power input, typically 0.7-0.95 for most motors.

Q2: What does power factor represent?
A: Power factor (PF) is the ratio of real power to apparent power, representing phase difference between voltage and current.

Q3: How do I find the current (I) value?
A: Measure with a clamp meter or check motor nameplate ratings under full load conditions.

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

Q5: Why is my calculated power lower than nameplate rating?
A: Nameplate shows maximum capacity; actual power depends on load conditions and operating parameters.