1. What is 3-Phase Power Calculation?

Definition: This calculator converts three-phase electrical current measurements to kilowatts (kW) of power.

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

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_{kW} \) — Power in kilowatts
• \( V \) — Line-to-line voltage (volts)
• \( I \) — 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 in an AC system and the phase difference between voltage and current.

3. Importance of 3-Phase Power Calculation

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

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, and PF ≤ 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 to useful work (typically 0.8-0.95).

Q2: Should I use line-to-line or line-to-neutral voltage?
A: Always use line-to-line (phase-to-phase) voltage for this calculation.

Q3: What if I don't know the power factor?
A: For estimation, use 0.8 for motors or 1.0 for purely resistive loads. For precise measurements, use a power meter.

Q4: How does this differ from single-phase calculation?
A: Single-phase uses P=VI×PF/1000 without the √3 factor. Three-phase systems are more efficient for power distribution.

Q5: Can I calculate current from kW with this formula?
A: Yes, rearrange the formula: \( I = \frac{P_{kW} \times 1000}{V \times PF \times \sqrt{3}} \).