Transformer Efficiency Calculator

Calculate transformer efficiency, losses, and regulation at various load levels per IEEE C57 standards.

Nameplate kVA rating.
kVA
Iron/core losses. Constant regardless of load.
W
I²R losses at rated current.
W
Percentage of full load.
%
Power factor of the load.

Results

Output Power-kW
Total Losses-W
Efficiency-%
Max Efficiency Load-%
Approx. Regulation-%
References: IEEE C57.12 — Transformers; NEC Article 450