1. What is 3-Phase kVA?

Definition: kVA (kilovolt-amperes) is a unit of apparent power in an electrical circuit. For 3-phase systems, it accounts for all three phases.

Purpose: This calculator helps determine the apparent power in a 3-phase electrical system based on voltage and current measurements.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \text{kVA} \) — Apparent power (kilovolt-amperes)
• \( V \) — Line-to-line voltage (volts)
• \( I \) — Current (amps)
• \( \sqrt{3} \) — Constant for 3-phase power calculation (≈1.732)

Explanation: The formula multiplies voltage and current by √3 to account for the three phases, then divides by 1000 to convert to kVA.

3. Importance of 3-Phase kVA Calculation

Details: Proper kVA calculation is essential for sizing transformers, circuit breakers, and other electrical equipment in industrial and commercial settings.

4. Using the Calculator

Tips: Enter the line-to-line voltage in volts and the current in amps. Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between kVA and kW?
A: kVA is apparent power (volts × amps), while kW is real power (kVA × power factor). kVA includes both real and reactive power.

Q2: Why do we multiply by √3 in 3-phase calculations?
A: The √3 factor accounts for the phase difference between the three phases in a balanced system.

Q3: Is this formula for line-to-line or line-to-neutral voltage?
A: This formula uses line-to-line (phase-to-phase) voltage.

Q4: Can I use this for single-phase calculations?
A: No, for single-phase use: kVA = (V × I) / 1000 (without the √3 factor).

Q5: What's a typical power factor for calculations?
A: This calculator gives apparent power (kVA). For real power (kW), you'd need to know the power factor (typically 0.8-0.95 for motors).