How does a generator breaker interlock work to ensure safe operation of a generator and prevent backfeeding into the utility grid?

A generator breaker interlock is a safety device that prevents a generator from backfeeding into the utility grid. It works by physically preventing the generator breaker and the main utility breaker from being turned on at the same time. This ensures that the generator is only supplying power to the home or building it is connected to, and not sending electricity back into the grid, which can be dangerous for utility workers.