What is the function of a transfer switch?

The function of a transfer switch is to enable the switching between multiple load conductor connections from one power source to another, which is essential in various applications such as emergency power systems. When there is a power outage, a transfer switch allows for the seamless transition from the primary power source, such as the utility grid, to a backup power source like a generator. This ensures that critical loads remain powered during an outage without the risk of backfeeding, which can create hazardous conditions for utility workers and equipment damage.

The transfer switch also serves to isolate the two sources effectively to maintain safety and operational integrity. Therefore, its primary role is to manage power source changes, ensuring that electrical systems continue to function properly during transitional periods between different power sources.