1. What is the 3-Phase Power Formula?

The 3-phase power formula calculates the real power (in watts) in a balanced three-phase electrical system. It accounts for the line-to-line voltage, current, and power factor of the system.

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)
• \( PF \) — Power factor (unitless, between 0 and 1)
• \( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

Explanation: The formula calculates the actual power being used in the system, accounting for the phase relationship between voltage and current.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for sizing electrical equipment, determining energy consumption, calculating efficiency, and ensuring proper circuit protection.

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.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor is the ratio of real power to apparent power, representing how effectively current is being converted into useful work. It ranges from 0 to 1.

Q2: What's the difference between line-to-line and line-to-neutral voltage?
A: In 3-phase systems, line-to-line voltage is between any two phases, while line-to-neutral is between a phase and neutral. Line-to-line is √3 times higher.

Q3: When should I use this formula?
A: Use for balanced 3-phase AC systems. For single-phase, use P = V × I × PF. For unbalanced 3-phase, calculate each phase separately.

Q4: What's a typical power factor value?
A: For resistive loads (heaters, incandescent lights), PF ≈ 1. For inductive loads (motors, transformers), PF is typically 0.8-0.9.

Q5: How does this relate to kVA?
A: Apparent power (kVA) is V × I × √3 (without PF). Real power (kW) is kVA × PF. This calculator gives real power in watts.