ECN Forum Forums General Topics of the Trade General Discussion Area Transformers: what determines the amp rating?

Spark Master Flash,
If there is no label, and the transformer is energized, you could figure out the primary voltage and secondary voltage with a meter, but I don't know of a field test that would determine the kVA rating. If it isn't energized, then I don't know of a field test that would determine the exact voltage configuration either.