Transformer kVA Calculator

STEP BY STEP

How to use transformer kva calculator

1. Check the input units and assumptions.
2. Review the result and example.

IN PRACTICE

Example

For a 480 V balanced three-phase load drawing 30 A: kVA = 1.732 × 480 × 30 ÷ 1,000 = about 24.94 kVA. This is the load calculation, not an instruction to select the smallest possible transformer rating.

GOOD TO KNOW

Which assumptions should I check?

A kVA result does not check inrush, harmonics, continuous loading, ambient temperature, enclosure, insulation class, impedance, fault current or local electrical code. Motors and nonlinear loads can require extra design margin. Always select equipment using manufacturer and code requirements.