Shunt trip device for a molded case circuit breaker

A molded case circuit breaker comprising:

• a molded housing including a main breaker cover;
• a first terminal and a second terminal mounted in the case;
• a contact electrically coupled to the first terminal;
• a moveable contact electrically coupled to the second terminal;
• an operating mechanism having a pivoting member moveable between an ON position, an OFF position and a TRIPPED position, wherein the pivoting member is coupled to the moveable contact;
• an intermediate latching mechanism mounted in the housing and coupled to the operating mechanism;
• and
• a trip unit having a trip bar and coupled to the moveable contact and the second terminal with the trip unit in selective operative contact with the intermediate latching mechanism;
• and,
• an accessory socket formed in the main breaker cover on either side of an opening for the pivoting member, with the accessory socket in communication with the housing;
• a latching protrusion in the socket for engaging an accessory;
• an accessory cover sized to cover the accessory mounted in the accessory socket;
• and,
• a shunt trip device installed in the socket, the shunt trip device comprising:
• a base and a top mount;
• a solenoid to remotely trip the breaker, having a plunger mounted on the base;
• a shunt trip bar actuator, having a high probe, a middle portion, and a low probe, with the shunt trip bar actuator attached at the middle portion with a mounting pin to a push plate member mounted on the base and aligned with the plunger, wherein the middle portion of the shunt trip bar actuator provides a fulcrum for pivoting one of the high probe and low probe toward and into an opening in a socket in the cover of the circuit breaker to selectively contact the trip bar;
• a spring installed between the solenoid and the push plate member;
• and,
• a clearing switch mounted on the base and connected in series with the solenoid, with the clearing switch having a crossbar switch actuator in contact with the operating mechanism.

A method for tripping a molded case circuit breaker having an operating mechanism configured to open and close a power circuit, a trip unit with an intermediate latch and a main breaker cover, from a remote location, the method for tripping comprising the steps of:

• closing the circuit breaker with the operating mechanism;
• installing a shunt trip device in the breaker cover, the shunt device having a solenoid and a clearing switch wired in series with the solenoid in operative contact with the trip unit, with the shunt trip device including a shunt trip bar actuator having a high probe, a middle portion and a low probe, wherein the middle portion of the shunt trip bar actuator provides a fulcrum for pivoting one of the high probe and low probe toward and into an opening in the cover and contacting the trip unit, and the clearing switch in operative contact with the operating mechanism;
• providing power to the solenoid through the clearing switch from a remote location, whereby the solenoid forces the trip unit to unlatch the operating mechanism to open the power circuit;
• and
• moving the clearing switch to an open position with the operating mechanism, whereby power to the solenoid is cut off.

A circuit breaker comprising:

• a molded housing including a base and a cover;
• a means for connecting a load to the circuit breaker, mounted in the housing;
• a means for connecting an electrical line to the circuit breaker;
• a means for coupling electrically to the means for connecting an electrical line;
• a movable means for contacting the means for connecting an electrical line to a means for operating mounted in the housing coupled with the means for operating having a pivoting member movable between an ON position, an OFF position, and a TRIPPED position, with the pivoting member coupled to the movable means for contacting and with the means for operating coupled to an intermediate means for latching the means for operating;
• a means for tripping coupled to the movable means for contacting and the means for connecting a load with the intermediate means for latching, wherein the means for tripping includes a means for releasing under a short circuit condition and a means for releasing under an overload condition;
• and
• a means for remotely tripping the circuit breaker mounted in a compartment in the cover and operatively connected to the means for tripping.