A single-phase power transformer is a device that uses a single-phase AC current. This means that the transformer depends on the voltage cycle, which operates in an integrated time phase. These transformers are used to lower remote electrical signals to the power level, which are used in light commercial applications as well as residential applications.

The change in current is determined by the ratio of the primary winding (input) to the secondary winding (output). Many single-phase transformers allow adjustable speed ratios, yet others have a fixed 1: 1 ratio that can be used to isolate and isolate circuits.

The maximum voltage in single-phase transformers varies according to industrial regulations and installation infrastructure.