1. What is 3-Phase Power Calculation?

The 3-phase power calculation determines the real power (in kilowatts) delivered by a three-phase electrical system. It accounts for voltage, current, and power factor, which represents the phase difference between voltage and current waveforms.

2. How Does the Calculator Work?

The calculator uses the 3-phase power formula:

Where:

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

Explanation: The formula calculates real power by accounting for all three phases and the phase angle between voltage and current.

3. Importance of Power Factor

Details: Power factor represents the ratio of real power to apparent power. A lower PF means more current is required to deliver the same amount of real power, increasing losses in the system.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amperes, and power factor (typically 0.8-0.95 for industrial loads). All values must be positive with PF between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between kW and kVA?
A: kW is real power (what performs work), while kVA is apparent power (voltage × current). kW = kVA × PF.

Q2: Why use line-to-line voltage?
A: Most 3-phase systems are specified with line-to-line voltage (e.g., 480V, 208V), which is what's measured between any two phases.

Q3: What's a typical power factor value?
A: Resistive loads have PF=1, motors typically 0.8-0.9, and heavily inductive loads can be 0.5 or lower.

Q4: How does this differ from single-phase calculation?
A: Single-phase uses \( kW = (V \times I \times PF)/1000 \) without the \( \sqrt{3} \) factor.

Q5: Can I use this for DC power?
A: No, DC power is simply \( kW = (V \times I)/1000 \) as there's no phase angle or \( \sqrt{3} \) factor.