1. What is the 3-Phase Power Formula?

The 3-phase power formula calculates the real power in a balanced three-phase electrical system. It's commonly used in industrial and commercial power systems where three-phase power is standard.

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 three-phase systems (≈1.732)

Explanation: The formula accounts for the phase relationship in three-phase systems and the power factor which represents the ratio of real power to apparent power.

3. Importance of Power Factor

Details: Power factor is crucial in electrical systems as it affects efficiency. A low power factor (below 0.9) indicates poor utilization of electrical power and may result in additional charges from utility companies.

4. Using the Calculator

Tips: Enter line-to-line voltage (typically 208V, 240V, 480V, etc.), current in amps, and power factor (1 for purely resistive loads, typically 0.8-0.95 for motors). All values must be valid (voltage > 0, current > 0, PF between 0-1).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between line-to-line and line-to-neutral voltage?
A: In 3-phase systems, line-to-line voltage is √3 times the line-to-neutral voltage. This calculator uses line-to-line voltage.

Q2: Can I use this for single-phase calculations?
A: No, for single-phase use P = V × I × PF without the √3 factor.

Q3: What is a typical power factor value?
A: Resistive loads have PF=1, motors typically 0.8-0.95, and heavily inductive loads can be 0.5 or lower.

Q4: How do I improve power factor?
A: Power factor correction capacitors can be added to counteract inductive loads.

Q5: Is this formula valid for unbalanced loads?
A: This simplified formula assumes balanced loads. For unbalanced systems, calculate each phase separately and sum the results.