What is the efficiency of a transformer when fully loaded or less?
Transformers from 1KVA through 1000KVA have full load efficiencies between 95% to 98.5%. Transformer losses appear in the core and windings. The core accounts for 1% or less of the name plate rating and the wire resistance losses account for 1% to 3% of the full-load rating. These losses are dissipated as heat. Copper and aluminum wire are used as they are the best commercial metals for conducting electricity.
