What is the “regulation” of a transformer?
The term “regulation” refers to voltage regulation of a transformer. The voltage regulation is the difference between the open circuit output voltage of the transformer and the full-load output voltage. This is usually expressed as a percentage. Regulation of small PCB transformer may be as high as 20% , with power transformer up to 1,000VA usually having regulation 7%. Larger transformer will have even lower regulation, with around 3% regulation being typical for transformers around 10KVA. For example, a typical 100VA control transformer rated at 24v full load (aprox 4A) may have an open circuit output voltage of 25.2v Voltage Regulation Voltage Regulation = (Vo/c – Vfl) / Vfl = (25.
