1. What is 3-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 large loads and industrial applications.

2. How Does the Calculator Work?

The calculator uses the 3-phase power formula:

Where:

• \( P \) — Power in watts (W)
• \( V \) — Line-to-line voltage in volts (V)
• \( I \) — Current in amperes (A)
• \( PF \) — Power factor (unitless, 0 to 1)
• \( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

Explanation: The formula calculates real power in a balanced three-phase system, accounting for the phase difference between voltage and current.

3. Importance of Power Factor

Details: Power factor (PF) represents the ratio of real power to apparent power. A PF of 1 indicates all power is real (useful) power, while lower values indicate reactive power that doesn't do useful work but still requires current flow.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amps, and power factor (between 0 and 1). All values must be positive numbers with power factor between 0 and 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 (208V line-to-line = 120V line-to-neutral).

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

Q3: What is a typical power factor value?
A: Motors typically have PFs of 0.8-0.9, resistive loads have PF=1, and heavily inductive loads can have PFs as low as 0.5.

Q4: How does power factor affect energy costs?
A: Many utilities charge commercial customers extra for low power factor since it increases current flow without delivering useful power.

Q5: Can this formula be used for unbalanced loads?
A: No, this formula assumes a balanced 3-phase system. Unbalanced systems require more complex calculations.