Electrical 3 Phase Power Calculation Formula

3-Phase Power Formula:

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

Power (P):

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1. What is 3-Phase Power Calculation?

The 3-phase power calculation formula determines the real power in a balanced three-phase AC circuit. It accounts for the phase difference between voltage and current through the power factor.

2. How Does the Calculator Work?

The calculator uses the 3-phase power equation:

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

Where:

\( P \) — Real 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 the actual power being used in the system, as opposed to apparent power (VA) or reactive power (VAR).

3. Importance of Power Factor

Details: Power factor represents the efficiency of power usage in AC circuits. A PF of 1 means all power is real power (resistive loads), while lower PF indicates reactive components (inductive or capacitive loads) causing phase shift.

4. Using the Calculator

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

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 (e.g., 400V line-to-line = 230V line-to-neutral).

Q2: How does unbalanced load affect the calculation?
A: This formula assumes balanced load. For unbalanced systems, calculate power for each phase separately and sum them.

Q3: What's the difference between real, apparent, and reactive power?
A: Real power (W) does actual work, apparent power (VA) is voltage×current, reactive power (VAR) is stored in magnetic/ electric fields.

Q4: Why is power factor correction important?
A: Low PF increases current for same real power, causing higher losses and requiring larger conductors/equipment.

Q5: Can this be used for DC circuits?
A: No, DC power is simply P = V × I. The √3 and PF terms are specific to 3-phase AC systems.