1. What is 3-Phase Motor Power?

3-phase motor power refers to the electrical power consumed or produced by a three-phase alternating current motor. It's 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 3-phase power formula:

Where:

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

Explanation: The √3 factor accounts for the phase difference in three-phase systems. Power factor represents the ratio of real power to apparent power.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for sizing electrical components, determining energy consumption, assessing motor efficiency, and calculating operating costs.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amps, and power factor (typically 0.8-0.95 for motors). All values must be positive (voltage > 0, current > 0, 0 < PF ≤ 1).

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor is the ratio of real power (doing actual work) to apparent power (product of voltage and current). It ranges from 0 to 1, with 1 being most efficient.

Q2: What's the difference between line and phase voltage?
A: In 3-phase systems, line voltage is between any two lines, while phase voltage is between a line and neutral. For star connections, line voltage = √3 × phase voltage.

Q3: Why use √3 in the formula?
A: The √3 accounts for the 120° phase difference between the three phases in a balanced system.

Q4: What's a typical power factor for motors?
A: Induction motors typically have power factors between 0.8 and 0.95 at full load, lower at partial loads.

Q5: Can this calculate mechanical power output?
A: No, this calculates electrical input power. Mechanical output power would be this value multiplied by the motor's efficiency.