An overcurrent protection device for a circuit to be monitored, having at least one trigger unit, which is configured for an interruption of the circuit in at least one trigger situation and which includes at least one conductor section which is configured for a conduction of a current to be monitored, at least one conductive trigger element, which includes at least one thermo magnetically-shiftable material configured for a magnetic property change in dependence on the temperature induced by a current that flows through the conductor section, a conductive magnetic module, a conductive magnetic core, the conductive magnetic module being movable between a first position faced against the conductive trigger element permitting the conduction of the current through the conductor section and a second position faced against said conductive magnetic core breaking the conduction of the current through the conductor section.

A clapping type electromagnetic tripping system comprises an iron core with a U-shaped structure, an armature, a heating element, a bimetallic element and a connecting plate; a bracket extends into a U-shaped groove of the iron core and is fixedly connected with the iron core, and a wire connecting the heating element and the connecting plate surrounds the iron core and the bracket; the bracket twined round by the wire is fixedly connected with the middle part of the heating element, the bottom end of the heating element and the bottom end of the bimetallic element are fixedly connected with a supporting member together, and the armature is hung on the bracket surrounded by the wire; and the armature and the iron core twined round by the wire are arranged oppositely to form a magnetic loop, and one end of the armature is attracted by the iron core so as to swing when short-circuit current is generated. The clapping type electromagnetic tripping system disclosed by the present invention-creation is simple and reasonable in structure and can enable the armature to be attracted reliably.

A circuit breaker including a housing, a line terminal, a load terminal, a trip device, a thermal trip mechanism, a magnetic trip mechanism, an arc extinguish chamber, a handle assembly, a one-piece line terminal lug, and a one-piece load terminal lug. The trip device includes a link assembly and a movable contact assembly. The movable contact assembly includes a movable contact; the thermal trip mechanism includes a bimetallic strip and a thermal trip hook connected to a first end of the bimetallic strip. The magnetic trip mechanism includes a moving iron core, a stationary iron core, a magnetic spring, and a firing pin. The one-piece line terminal lug includes a first bottom part and an inlet connection part and is configured to directly introduce an external power into the circuit breaker. The first bottom part is disposed at the bottom of the line terminal.