A movable contact assembly for an electrical switching apparatus is provided. The movable contact assembly includes a number of shunts, and, a carriage assembly including two sidewalls and a contact arm assembly. The carriage assembly sidewalls are disposed in a spaced relation. The contact arm assembly includes a plurality of contact arms, a number of isolation members, a number of movable contacts, and an axle. Each contact arm defines an opening, One movable contact is disposed on each contact arm. Each contact arm is rotatably coupled to the axle with the axle extending through the contact arm opening. Each isolation member is disposed adjacent at least one contact arm. Each isolation member is coupled to, and in electrical communication with the adjacent contact arm. The shunts are coupled to, and in electrical communication with, the isolation members. In this configuration, no shunt operatively engages a contact arm.

A contact system of a circuit breaker includes a fixed contact. The contact system also includes a moveable contact arm assembly comprising at least one moveable contact arm having a moveable contact thereon, the moveable contact arm moveable to define a closed condition and a blow open condition. The contact system further includes a carrier assembly operatively coupled to the moveable contact arm. The contact system yet further includes a latch plate operatively coupled to the carrier assembly. The contact system also includes a trip shaft operatively coupled to the carrier assembly, the trip shaft having a non-circular region defining an engagement surface disposed in contact with the latch plate in the closed condition. The contact system further includes a biasing portion of the moveable contact arm configured to rotate the trip shaft out of engagement with the latch plate and into the blow open condition.

A circuit breaker crossbar assembly includes a crossbar having a first and second segment, the first and second segment each operatively coupled to a respective moveable contact arm assembly. Also included is a coupling segment disposed between the first and second segment, the crossbar and the coupling segment rotatable about an axis. Further included is at least one support assembly operatively coupled to the coupling segment. The support assembly includes a bushing coupled to the coupling segment and rotatable with the crossbar and the coupling segment. The support assembly also includes a support bracket configured for affixation to a stationary structure and disposed adjacent to the bushing, the bushing rotatable relative to the support bracket. The support assembly further includes a fixing bracket engaged with the support bracket and disposed adjacent to the bushing, the bushing rotatable relative to the fixing bracket.

A moveable contact arm assembly includes a moveable contact arm having a moveable contact thereon. Also included is a carrier assembly operatively coupled to the moveable contact arm. Further included is a first end plate operatively coupled to the carrier assembly and a bottom bracket operatively coupled to the first end plate. Yet further included is a first latch member coupled to the bottom bracket, the first latch member comprising a first guiding surface and defining a first recess portion. Also included is a guide pin extending from the carrier assembly and in contact with the first guiding surface of the first latch member during movement of the moveable contact arm assembly. Also included is a first stop pin extending from the carrier assembly and disposed in the first recess portion of the first latch member in the blow open condition of the circuit breaker.

An air circuit breaker according to an embodiment of the present disclosure comprises: a body portion provided with an opening having one open side; a plurality of movers which are rotatably coupled to the body portion and inserted in the opening; and a plurality of contact springs which are accommodated in the body portion and provide the plurality of movers respectively with an elastic force, wherein the plurality of contact springs comprise a plurality of first contact springs, and a plurality of second contact springs arranged among the plurality of first contact springs. The plurality of first contact springs may provide the plurality of movers with greater elastic force as compared with the plurality of second contact springs.