Abstract: Improvement in a circuit breaker employing a fixed pole piece associated with a movable magnetic core within a tube containing damping fluid wherein the side walls of the tube are transparent in order to facilitate the inspection of internal components. Calibrations can be provided on the side walls as well. Additionally, the tube is preferably made of resinous materials which is heat sealable to the end cap carrying the pole piece to which the breaker tripping armature is attracted by overload sensed by a coil surrounding the movable core and upon overload causing the armature to move to the pole piece and open the circuit breaker contact.

Abstract: A circuit breaker having the generally rectangular case with an actuating switch handle on one edge and terminals at the opposite edge is provided with an auxiliary switch receptacle at the edge by the terminal. Retainer means is provided for holding the auxiliary switch in the receptacle and an access opening is provided through the edge wall for communication between the switch actuating member and a portion of the breaker mechanism moving in response to breaker contact opening and closing. A U-shaped retainer is preferably used to retain the switch in the receptacle by passing prongs thereof through the holes in the switch walls and the aligned switch holes. The actuator member may be in accordance with various types of mechanisms, either a compressible member or a rigid slide, and in either case is moved by the breaker mechanism into the actuating means of the switch.