Free kVA to Amperage Calculator

The kVA to Amperage Calculator is a free online tool that converts apparent power (kVA) into electrical current (amps) for alternating current circuits. It supports both single‑phase and three‑phase systems, making it a versatile electrical amperage calculator for load planning and equipment sizing. By entering the power load and voltage, you obtain the corresponding amperage instantly.

Basic Formula for kVA to Amps

Apparent power $S$ (kVA), voltage $V$ (kV), and current $I$ (A) are related by:

$$I = \frac{S}{V}$$

When voltage is given in volts, convert kVA to VA (multiply by 1000) and then divide:

$$I = \frac{S \times 1000}{V}$$

Single‑Phase kVA to Amps

For a single‑phase system, use the same formula:

$$I_{\text{single}} = \frac{S \times 1000}{V}$$

where $V$ is the line voltage in volts. This is the standard single phase kVA to amps connection.

Three‑Phase kVA to Amps

In three‑phase systems, the relationship depends on the voltage reference:

Line‑to‑Line Voltage

$$I_{\text{3ph,LL}} = \frac{S \times 1000}{V_{LL} \times \sqrt{3}}$$

Line‑to‑Neutral Voltage

When the neutral line is available:

$$I_{\text{3ph,LN}} = \frac{S \times 1000}{V_{LN} \times 3}$$

These formulas are essential for any three phase kVA to amps calculation.

Converting Amps to kVA (Reverse Calculation)

The calculator can also serve as an amperage to kVA converter. The reverse formulas are:

• Single‑phase: $S = \frac{I \times V}{1000}$
• Three‑phase (line‑to‑line): $S = \frac{I \times V_{LL} \times \sqrt{3}}{1000}$
• Three‑phase (line‑to‑neutral): $S = \frac{I \times V_{LN} \times 3}{1000}$

These conversions let you derive apparent power from measured current and voltage.

Using the kVA to Amps Calculator

The tool features a straightforward interface:

1. Select load distribution: single‑phase or three‑phase (line‑to‑line / line‑to‑neutral).
2. Enter the apparent power in kilovolt‑amperes.
3. Input the voltage in volts (or kilovolts if preferred).

After providing these values, the calculator displays the current in amperes immediately. This eliminates manual computation and reduces errors.

Example Calculation

How many amps can a 50 kVA transformer deliver?
Assume a 50 kVA transformer connected to a 240 V three‑phase line‑to‑line supply:

$$I = \frac{50 \times 1000}{240 \times \sqrt{3}} \approx \frac{50\,000}{415.69} \approx 120.3\ \text{A}$$

If the same transformer is used on a 240 V single‑phase system, the current would be:

$$I = \frac{50 \times 1000}{240} \approx 208.3\ \text{A}$$

This example highlights the difference between single‑phase and three‑phase installations.

Summary

The kVA to Amperage Calculator simplifies electrical current determination. Whether you are sizing conductors, selecting circuit breakers, or designing power distribution, this apparent power to current calculator provides fast, reliable results. Use it for both single‑phase and three‑phase applications to ensure your system operates within safe limits.