1. What is Three-Phase Motor Power?

Three-phase motor power refers to the electrical power consumed by a three-phase AC motor during operation. It is calculated using voltage, current, and power factor to determine the actual power being used by the motor.

2. How Does the Calculator Work?

The calculator uses the three-phase power formula:

Where:

• \( P \) — Power in watts (W)
• \( V \) — Line-to-line voltage in volts (V)
• \( I \) — Current in amperes (A)
• \( PF \) — Power factor (dimensionless, 0 to 1)
• \( \sqrt{3} \) — Mathematical constant ≈ 1.732

Explanation: The formula calculates the real power consumed by a three-phase motor, accounting for the phase relationship between voltage and current through the power factor.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for motor sizing, energy efficiency analysis, electrical system design, and determining operating costs. It helps in selecting appropriate circuit protection and wiring.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amperes, and power factor (between 0 and 1). All values must be positive numbers with voltage and current greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor and why is it important?
A: Power factor represents the ratio of real power to apparent power. It indicates how effectively electrical power is being used. Low power factor means poor efficiency and may incur utility penalties.

Q2: What is the difference between single-phase and three-phase power?
A: Three-phase systems use three alternating currents with 120-degree phase differences, providing more consistent power delivery and higher efficiency for industrial applications compared to single-phase.

Q3: What are typical power factor values for motors?
A: Induction motors typically have power factors between 0.8 and 0.9 at full load, dropping significantly at lighter loads. Synchronous motors can maintain unity power factor.

Q4: How does motor load affect power consumption?
A: Power consumption increases with motor load. At full load, motors operate most efficiently. Underloading reduces efficiency and power factor, increasing operating costs.

Q5: Can this formula be used for motor sizing?
A: Yes, this calculation helps determine the power requirements for motor selection, but additional factors like starting torque, duty cycle, and safety margins should also be considered.