1. What is 3-Phase Power Calculation?

The 3-phase power calculation determines the real power in a three-phase electrical system. It accounts for the voltage, current, and power factor in a balanced three-phase circuit.

2. How Does the Calculator Work?

The calculator uses the 3-phase power formula:

Where:

• \( P \) — Real power in watts (W)
• \( V \) — Line-to-line voltage in volts (V)
• \( I \) — Current in amperes (A)
• \( \cos\phi \) — Power factor (dimensionless, 0-1)

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

3. Importance of Power Calculation

Details: Accurate power calculation is essential for electrical system design, load balancing, energy efficiency assessment, and equipment sizing.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amps, and power factor (between 0 and 1). Typical power factor for motors is 0.8-0.9.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between line and phase voltage?
A: In a 3-phase system, line voltage is between any two lines, while phase voltage is between any line and neutral. For star connections, line voltage = √3 × phase voltage.

Q2: Why is power factor important?
A: Lower power factor means more current is needed for the same real power, increasing losses and requiring larger conductors.

Q3: Does this formula work for unbalanced loads?
A: No, this formula is for balanced three-phase systems. Unbalanced systems require more complex calculations.

Q4: What's typical power factor for industrial equipment?
A: Induction motors: 0.8-0.9, fluorescent lighting: 0.7-0.9, resistance heating: 1.0.

Q5: How can power factor be improved?
A: Using capacitors for power factor correction, selecting properly sized motors, and avoiding lightly loaded transformers.