3 Phase AC Power Calculation Formula

3-Phase Power Formula:

\[ P = \sqrt{3} \times V \times I \times PF \]

3-Phase Power (P):

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1. What is 3-Phase AC Power?

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

2. How Does the Calculator Work?

The calculator uses the 3-phase power formula:

\[ P = \sqrt{3} \times V \times I \times PF \]

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 3-phase system, accounting for the phase difference between voltage and current through 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 PF of 1 means all power is real (useful) power, while lower PF indicates 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 amperes, and power factor (typically between 0.8-1.0 for most industrial loads). All values must be valid (voltage > 0, current > 0, 0 ≤ PF ≤ 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 between any two phases, while line-to-neutral is between a phase and neutral. Line-to-line is √3 times line-to-neutral.

Q2: What is a typical power factor value?
A: Induction motors typically have PF of 0.8-0.9 at full load. Resistive loads have PF=1. Capacitors can improve PF.

Q3: How does this differ from single-phase power calculation?
A: Single-phase power is P = V × I × PF (no √3 factor). 3-phase delivers more power with less conductor material.

Q4: What is apparent power vs real power?
A: Apparent power (VA) is V × I, while real power (W) is V × I × PF. The difference is reactive power (VAR).

Q5: When should I use this calculation?
A: For balanced 3-phase systems to determine real power consumption or required power supply capacity.