1. What is 3-Phase Power Calculation?

The 3-phase power calculation converts current (amps) to power (kilowatts) in a three-phase electrical system. This is essential for sizing electrical equipment, calculating energy consumption, and designing electrical systems.

2. How Does the Calculator Work?

The calculator uses the 3-phase power formula:

Where:

• \( V \) — Line-to-line voltage (volts)
• \( I \) — Current (amps)
• \( PF \) — Power factor (unitless, 0 to 1)
• \( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)
• 1000 — Conversion factor from watts to kilowatts

Explanation: The formula accounts for the phase relationship in 3-phase systems and the efficiency represented by the power factor.

3. Importance of Power Factor

Details: Power factor (PF) represents the ratio of real power to apparent power. A higher PF (closer to 1) indicates more efficient power usage. Industrial loads often have PF between 0.8-0.95.

4. Using the Calculator

Tips:

• Enter line-to-line voltage (typically 208V, 240V, 380V, 400V, 415V, 480V, or 600V)
• Current should be measured or known from equipment specifications
• Power factor defaults to 0.8 (common industrial value) but can be adjusted

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between line-to-line and line-to-neutral voltage?
A: In 3-phase systems, line-to-line voltage is between any two phases, while line-to-neutral is between one phase and neutral. The calculator uses line-to-line voltage.

Q2: How accurate is this calculation?
A: The calculation is mathematically precise, but accuracy depends on precise voltage, current, and power factor measurements.

Q3: What if I don't know the power factor?
A: For resistive loads (heaters, incandescent lights), use 1.0. For motors, 0.8 is typical. For precise calculations, measure actual PF.

Q4: Can I use this for single-phase calculations?
A: No, single-phase uses a different formula (kW = V × I × PF / 1000). Use a single-phase calculator instead.

Q5: Why is √3 used in the formula?
A: √3 accounts for the 120° phase shift between the three phases in a balanced 3-phase system.