An interlock device is designed to allow a generator to provide backup power in such a way that it (a) prevents main and generator power to be connected at the same time, and (b) allows circuit breakers to operate normally without interference in the event of an overload condition.

Which is better a transfer switch or interlock?

Compared to a transfer switch, which is limited to a particular number of circuits, an interlock kit allows you to run power from a generator to any circuit within the electrical panel. While this is good in theory, there’s a risk of overloading the generator if it’s not sized according to the load.

Why do you need a circuit breaker interlock?

The function of the racking mechanism interlock is to prevent the breaker from moving from the connection position before the breaker is in the open position. … Racking interlocks prevent a circuit breaker from being connected to energized bus in the closed position.