Electrical & Controls

Transformer full-load current

Primary or secondary full-load current from kVA and voltage.

kVA
V

Calculating…

How it's calculated

Three-phase: I = kVA × 1000 ÷ (√3 × V) Single-phase: I = kVA × 1000 ÷ V

Enter the voltage of the side you are interested in. A 500 kVA transformer is about 722 A per phase on a 400 V secondary. The same formula gives the full-load current of a generator from its kVA rating.