Power Calculation Formula for 3 Phase

3-Phase Power Formula:

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

Power (P_kW): kW

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1. What is 3-Phase Power Calculation?

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

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

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 in kilowatts
\( V \) — Line-to-line voltage (volts)
\( I \) — Line current (amps)
\( PF \) — Power factor (unitless, 0 to 1)
\( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

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

3. Importance of 3-Phase Power Calculation

Details: Accurate power calculation is essential for sizing equipment, determining energy consumption, and ensuring electrical system safety.

4. Using the Calculator

Tips: Enter the line-to-line voltage in volts, line 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 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: Is this formula for balanced systems only?
A: Yes, this formula assumes a balanced three-phase system with equal loads on all phases.

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. The default 0.8 is common for industrial loads.

Q4: Should I use line or phase voltage?
A: Use line-to-line voltage (the voltage between any two phases) for this calculation.

Q5: How do I convert kW to HP?
A: Multiply kW by 1.341 to get horsepower (HP).