What Is A Shunt Trip? A shunt trip breaker is a type of circuit breaker that, in addition to automatically tripping during an electrical surge and cutting off power, also can be triggered by a separate electrical signal to disconnect before a power surge occurs. A shunt breaker has three connections: to the power source, the output, and a third contact usually hooked into a safety system such as a smoke detector. How Do They Work? Shunt trip breakers offer an added degree of protection against power surges, and although they serve a similar purpose to regular circuit breakers, they work somewhat differently. A circuit breaker will automatically trip when it…