kW Formula 3 Phase

3-Phase Power Formula:

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

Power (kW):

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1. What is 3-Phase Power Calculation?

Definition: This calculator computes the real power in kilowatts (kW) for a three-phase electrical 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:

\( P_{kW} \) — Real power (kilowatts)
\( V \) — Line-to-line voltage (volts)
\( I \) — Current (amps)
\( PF \) — Power factor (unitless, between 0 and 1)
\( \sqrt{3} \) — Constant for three-phase systems (≈1.732)

Explanation: The formula accounts for all three phases in the system and the phase difference between voltage and current.

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, current in amps, and power factor (default 0.8). All values must be > 0, with PF between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between line and phase voltage?
A: In 3-phase systems, line voltage is between any two lines, while phase voltage is between any line and neutral.

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

Q3: What's a typical power factor value?
A: Motors typically have PF of 0.8-0.9, while purely resistive loads have PF=1.

Q4: How does this differ from single-phase power calculation?
A: Single-phase uses P=VI×PF, without the √3 factor and divided by 1000 for kW.

Q5: Can I use this for DC systems?
A: No, for DC use P=VI (no power factor or √3 needed).