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3 Phase AC Power Calculation

3-Phase Power Formula:

\[ P_{kW} = \frac{V \times I \times PF \times \sqrt{3}}{1000} \]

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1. What is 3-Phase AC Power Calculation?

Definition: This calculator computes the real power in kilowatts (kW) for a balanced three-phase alternating current (AC) system.

Purpose: It helps electrical engineers, technicians, and electricians determine the actual power consumption in three-phase systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ P_{kW} = \frac{V \times I \times PF \times \sqrt{3}}{1000} \]

Where:

Explanation: The formula accounts for all three phases and the phase difference between voltage and current through the power factor.

3. Importance of 3-Phase Power Calculation

Details: Accurate power calculation is essential for proper equipment sizing, energy efficiency analysis, and electrical system design.

4. Using the Calculator

Tips: Enter the line-to-line voltage in volts, line current in amps, and power factor (default 0.8). Power factor must be between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor is the ratio of real power to apparent power, representing how effectively current is being converted into useful work.

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

Q3: What's a typical power factor value?
A: Industrial loads typically have PF between 0.8-0.95. Resistive loads have PF=1, while inductive loads have lower PF.

Q4: Is this formula for balanced systems only?
A: Yes, this formula assumes a perfectly balanced three-phase system with equal loads on all phases.

Q5: How do I measure line-to-line voltage?
A: Use a multimeter to measure voltage between any two phase conductors in a three-phase system.

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