Which component is used to isolate circuits electrically in power distribution?

The isolation transformer is specifically designed to electrically isolate one circuit from another while allowing the transfer of AC power. This isolation is crucial for protecting sensitive equipment, enhancing safety by preventing electric shock, and reducing the risk of ground loops. Isolation transformers achieve this by using a magnetic coupling between the primary and secondary windings without a direct electrical connection, which helps to prevent harmful voltages from passing between the circuits.

In contrast, the auto transformer, step-up transformer, and step-down transformer serve different purposes related primarily to voltage transformation. An auto transformer functions by sharing a common winding between the primary and secondary sides, which makes it more efficient for voltage regulation but not for isolation. Step-up transformers increase voltage levels, while step-down transformers reduce voltage levels; neither function emphasizes isolation, making them unsuitable for this important role in power distribution.