1. What is Three-Phase Power?

Three-phase power is a common method of alternating-current electric power generation, transmission, and distribution. It is more efficient than single-phase power for heavy industrial loads and large motors.

2. How Does the Formula Work?

The three-phase power formula is:

Where:

• \( P \) — 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 difference in three-phase systems and the efficiency represented by the power factor.

3. Importance of Power Factor

Details: Power factor (PF) represents the ratio of real power flowing to the load to the apparent power. A higher PF (closer to 1) indicates more efficient power usage.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amperes, and power factor (between 0 and 1). Typical power factors are 0.8-0.95 for industrial loads.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between line-to-line and line-to-neutral voltage?
A: In three-phase systems, line-to-line voltage is √3 times the line-to-neutral voltage (e.g., 400V line-to-line = 230V line-to-neutral).

Q2: Why is √3 used in the formula?
A: The √3 factor accounts for the phase difference (120°) between the three phases in a balanced system.

Q3: What is a typical power factor value?
A: Induction motors typically have 0.85 PF, corrected systems 0.95-1.0. Pure resistive loads have PF=1.

Q4: How does power factor affect power calculation?
A: Lower PF means more current is needed for the same real power, increasing losses in the system.

Q5: Can this formula be used for single-phase systems?
A: No, for single-phase use P = V × I × PF (without the √3 factor).