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Calculate the Power in a Three Phase Load

Three-Phase Power Formula:

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

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amps
kW

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1. What is Three-Phase Power Calculation?

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

Purpose: It helps electricians, engineers, and technicians calculate 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:

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

3. Importance of Three-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: What's a typical power factor value?
A: For motors, 0.8-0.9 is common. Resistive loads have PF=1, while inductive loads have lower power factors.

Q3: Is this formula for balanced three-phase systems?
A: Yes, this formula assumes all three phases are balanced with equal voltages and currents.

Q4: What's the difference between line and phase values?
A: Line voltage is between any two lines, phase voltage is between line and neutral. For delta systems, line voltage = phase voltage.

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

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