1. What is Kilovolt-Ampere (kVA)?

kVA (kilovolt-ampere) is a unit of apparent power in an electrical circuit. It represents the total power in a system, combining both real power (kW) and reactive power (kVAR). In three-phase systems, kVA is calculated using the line-to-line voltage and current.

2. How Does the Calculator Work?

The calculator uses the 3-phase kVA formula:

Where:

• \( V \) — Line-to-line voltage (volts)
• \( I \) — Current (amperes)
• \( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)
• 1000 — Conversion factor from VA to kVA

Explanation: The formula accounts for the phase difference in three-phase systems, providing the total apparent power.

3. Importance of kVA Calculation

Details: kVA is crucial for sizing electrical equipment like transformers, generators, and circuit breakers. It helps determine the capacity needed for electrical systems and ensures proper power distribution.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts and current in amperes. Both values must be positive numbers. The calculator automatically handles the three-phase calculation.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between kVA and kW?
A: kVA is apparent power (volts × amperes), while kW is real power (actual work done). kW = kVA × power factor.

Q2: Why use line-to-line voltage?
A: In three-phase systems, line-to-line voltage is the standard measurement between any two phases.

Q3: Can I use this for single-phase systems?
A: For single-phase, use kVA = (V × I)/1000 (without the √3 factor).

Q4: What are typical kVA ratings?
A: Common transformer sizes range from 5 kVA (small) to 2500 kVA (large industrial).

Q5: How does power factor affect kVA?
A: Lower power factor means more kVA is needed for the same kW output, increasing equipment sizing requirements.