Abstract: A circuit breaker rotary contact arm is used within a plurality of single pole modules ganged together to form a single multi-pole circuit breaker. To provide for use in quiescent conditions having high ampere ratings, low ampere rated rotary contact arm assemblies are combined in parallel to form a higher rated single pole module, which are then ganged together to form a single multi-pole circuit breaker having a high quiescent ampere rating.

Abstract: A circuit breaker rotary contact arm is used within a plurality of single pole circuit breakers ganged together to form a single multi-pole circuit breaker. To provide uniform contact wear among the associated circuit breaker contacts, the rotor carrying the rotary contact arm pivot is slotted to automatically position the rotary contact arm to allow for changes in the contact geometry while maintaining constant contact compressive forces. The individual circuit breakers connect with the central operation mechanism by means of a single pin.

Abstract: A molded case circuit breaker assembly using auxiliary switches to perform indication and control functions. The circuit breaker assembly having at least one pole comprising a stationary and a moveable contact where the moveable contact is connected to a moveable contact arm which is activated by a spring mechanism. The spring mechanism is affixed to an operating handle. A trip device, housed in a mid-cover of the molded case, separates the stationary and moveable contacts when a fault is sensed. The mid-cover comprises at least one auxiliary switch compartment, where a single auxiliary switch compartment is capable of housing multiple compatible auxiliary switches.

Abstract: An insulating plastic case and cover for a circuit breaker having complementary extensions on the cover and recesses on the base side walls to transfer internal stress from the base side walls to the cover during circuit interruption.