Patent ID: 8093964

Claim:
In a multiple-pole circuit breaker comprising a host circuit breaker having a basic mechanical structure that includes, for each pole a power input terminal and a power output terminal, a pair of contacts each of which is connected to a different one of said terminals and at least one of which is movable, a trip mechanism coupled to said movable contact for opening said contacts by disengaging said movable contact from the other contact in said pair, an electronic trip system that includes a plurality of current sensors producing signals related to the electrical current flow between said power input and output terminals, and a control circuit receiving said signals, detecting the occurrence of a fault condition, and producing an electrical trip signal when a fault condition is detected, a solenoid receiving said trip signal and coupled to said trip mechanism for moving said trip mechanism to open said contacts in response to said trip signal, and a reset mechanism coupled to said trip mechanism for resetting said trip mechanism and said movable contact, the improvement comprising an add-on module adapted to be attached to said basic mechanical structure and including multiple extended terminals each of which is adapted to replace one of said terminals for one of said poles, multiple electromechanical transducers each of which is coupled to one of said extended terminals for producing a mechanical movement in response to a predetermined magnitude of electrical current in the extended terminal to which that transducer is coupled, a mechanical trip link coupled to said electromechanical transducers and to said movable contacts for operating said trip mechanism in response to a predetermined movement of any of said transducers, and a mechanical reset arm coupling said reset mechanism to said mechanical actuator for resetting said actuator in response to the resetting of said host circuit breaker.