What does transformer regulation measure?

Transformer regulation specifically measures a transformer's ability to maintain a consistent voltage output under varying load conditions. This is an essential characteristic of a transformer, as it indicates how well the transformer can supply a stable voltage to the load despite fluctuations in demand.

When a transformer is loaded, its output voltage can drop due to internal impedance. Transformer regulation is expressed as the difference between the no-load voltage and the full-load voltage, often represented as a percentage. The better the regulation, the less the output voltage varies with the load, which is crucial for ensuring that electrical devices receive stable and reliable voltage for optimal operation.

The other options pertain to relevant transformer characteristics, but they do not directly relate to the concept of regulation. While efficiency involves energy loss, heat management is crucial for performance and safety, and load capacity speaks to the maximum safe load a transformer can handle, none of these aspects directly measure the voltage consistency provided in response to changing loads.