Abstract: A circuit breaker test system includes a circuit breaker under test having a deformable frame with an elongated slot, an elongated deformable portion adjacent the elongated slot and a movable portion adjacent the deformable portion, and a thermal trip assembly coupled to the movable portion. A calibration device includes a forked tool straddling the deformable portion. The trip assembly has a first thermal response. The calibration device rotates the tool in a first rotational direction and responsively deforms the deformable portion and moves the movable portion in a first direction, in order to calibrate the trip assembly for a second different thermal response. The calibration device rotates the tool in an opposite second rotational direction and responsively deforms the deformable portion and moves the movable portion in an opposite second direction, in order to re-calibrate the trip assembly for a third thermal response between the first and second thermal responses.

Abstract: A circuit breaker test system includes a circuit breaker under test having a deformable frame with an elongated slot, an elongated deformable portion adjacent the elongated slot and a movable portion adjacent the deformable portion, and a thermal trip assembly coupled to the movable portion. A calibration device includes a forked tool straddling the deformable portion. The trip assembly has a first thermal response. The calibration device rotates the tool in a first rotational direction and responsively deforms the deformable portion and moves the movable portion in a first direction, in order to calibrate the trip assembly for a second different thermal response. The calibration device rotates the tool in an opposite second rotational direction and responsively deforms the deformable portion and moves the movable portion in an opposite second direction, in order to re-calibrate the trip assembly for a third thermal response between the first and second thermal responses.

Abstract: A locking apparatus is for a circuit breaker including an enclosure having an opening with two sides and two ends, and two apertures on each of the sides proximate the ends. An operating mechanism includes a pivotal operating handle disposed through the opening. The operating handle includes a first position proximate one end of the opening and a second position proximate the other end of the opening. The locking apparatus is disposable proximate one of the ends of the opening. The locking apparatus includes a housing and a spring member interlocked with the housing. The spring member includes a first end and an opposite second end retained by the enclosure at the apertures at one of the ends when the operating handle is in the second position, or retained by the enclosure at the other apertures at the other of the ends when the handle is in the first position.

Abstract: A trip indicator is for a circuit breaker having a housing including first and second openings, separable contacts and an operating mechanism having an operating handle for opening and closing the separable contacts. The trip indicator includes a trip indicating member with a first end having a trip indicia and a second end with first and second projections. The first projection is engaged by a cradle of the operating mechanism when the separable contacts are not tripped, in order to prevent the trip indicia from being viewable at the second opening of housing. The first projection is disengaged and released when the separable contacts trip, causing the trip indicating member to move in order that the trip indicia is viewable at the second opening. A locking feature in which the second projection engages and locks operating handle, is also disclosed.

Abstract: A removable universal terminal assembly has a molded housing that clips onto an electric power switch and two terminal members that can be alternatively installed in the molded housing to provide either a quick connect termination or a binding post termination.

Abstract: A terminal assembly can be alternatively used to make either a pressure plate or screw type connection for connecting stranded wire or solid wire, respectively, to a power conductor of electric power apparatus such as a circuit breaker. An electrically insulative barrier has an elongated member with a lateral extension at one end having a recess that captures the head of the screw of a terminal collar for the pressure plate connection. As the screw is tightened, the collar is drawn toward the power conductor to clamp the stranded wire between the collar and one side of the power conductor. With the elongated member turned end for end, the screw is free to clamp the solid wire against the other side of the power conductor. Pairs of integral compliant latches on the elongated member accommodate quick conversion between the two types of connections.

Abstract: A trip spring electrical isolation device for a circuit breaker operating mechanism assembly, where the operating mechanism assembly has an operating arm and a cradle member with a trip spring disposed therebetween. The isolation device includes a non-conductive barrier structured to be coupled to either end of the trip spring.

Abstract: A circuit breaker includes separable contacts and an operating mechanism having a cradle for opening and closing the separable contacts. A trip mechanism cooperates with the cradle of the operating mechanism to trip open the separable contacts. The trip mechanism includes a bimetal conductor, which is electrically connected in series with the separable contacts. The trip mechanism is responsive to a predetermined condition of current flowing in the bimetal conductor. The trip mechanism also includes a magnetic yoke coupled to the bimetal conductor, an armature pivotally mounted to the magnetic yoke, and a spring biasing the armature away from the magnetic yoke. The spring is set apart from the bimetal conductor. The spring is coupled to the armature and engages the magnetic member.

Abstract: An operating mechanism assembly for a circuit breaker that includes a frame assembly, a metal pivot structure, and a trip device. The trip device has a cradle member structured to pivot about a pivot point and a trip assembly. The trip assembly is coupled to the frame assembly. The cradle member is pivotally disposed on the metal pivot structure.

Abstract: A unitary operating mechanism assembly for a circuit breaker that includes a frame assembly having a planar member with a first pivot point located thereon, a handle member rotatably attached to the frame assembly at the first pivot point and structured to move between a first, closed position, a second, open position having an intermediate position therebetween, and a third, reset position, an operating arm coupled to the handle member and structured to move between a first and second position, and a trip device attached to the frame assembly and structured to move the handle member between the first, closed position and the intermediate position upon the occurrence of a predefined condition. The trip device causes the handle member to rotate upon the occurrence of a predefined condition, such as an overcurrent, thereby causing the operating arm to rotate and wherein none of the components except the frame assembly is attached to the housing.

Abstract: An operating mechanism assembly for a circuit breaker that includes a frame assembly, a metal pivot structure, and a trip device. The trip device has a cradle member structured to pivot about a pivot point and a trip assembly. The trip assembly is coupled to the frame assembly. The cradle member is pivotally disposed on the metal pivot structure.

Abstract: A trip spring electrical isolation device for a circuit breaker operating mechanism assembly, where the operating mechanism assembly has an operating arm and a cradle member with a trip spring disposed therebetween. The isolation device includes a non-conductive barrier structured to be coupled to either end of the trip spring.

Abstract: A circuit breaker includes separable contacts and an operating mechanism having a cradle for opening and closing the separable contacts. A trip mechanism cooperates with the cradle of the operating mechanism to trip open the separable contacts. The trip mechanism includes a bimetal conductor, which is electrically connected in series with the separable contacts. The trip mechanism is responsive to a predetermined condition of current flowing in the bimetal conductor. The trip mechanism also includes a magnetic yoke coupled to the bimetal conductor, an armature pivotally mounted to the magnetic yoke, and a spring biasing the armature away from the magnetic yoke. The spring is set apart from the bimetal conductor. The spring is coupled to the armature and engages the magnetic member.

Abstract: A unitary operating mechanism assembly for a circuit breaker that includes a frame assembly having a planar member with a first pivot point located thereon, a handle member rotatably attached to the frame assembly at the first pivot point and structured to move between a first, closed position, a second, open position having an intermediate position therebetween, and a third, reset position, an operating arm coupled to the handle member and structured to move between a first and second position, and a trip device attached to the frame assembly and structured to move the handle member between the first, closed position and the intermediate position upon the occurrence of a predefined condition. The trip device causes the handle member to rotate upon the occurrence of a predefined condition, such as an overcurrent, thereby causing the operating arm to rotate and wherein none of the components except the frame assembly is attached to the housing.

Abstract: A circuit breaker includes separable contacts and an operating mechanism having a cradle for opening and closing the separable contacts. A trip mechanisms cooperates with the cradle of the operating mechanism to trip open the separable contacts. The trip mechanism includes a bimetal conductor, which is electrically connected in series with the separable contacts. The trip mechanism is responsive to a predetermined condition of current flowing in the bimetal conductor. The trip mechanism also includes a magnetic yoke coupled to the bimetal conductor, an armature pivotally mounted to the magnetic yoke, and a spring biasing the armature away from the magnetic yoke. The spring is set apart from the bimetal conductor. The spring is coupled to the armature and engages the magnetic member.

Abstract: An improved test button assembly for use in a circuit breaker includes a frame and a button member, with the button member being pivotably mounted on the frame. A pair of microswitches are mounted on a printed circuit board that is disposed on the frame. The button member is alternately engageable with the two microswitches, with one of the microswitches being connectable with a ground fault protection circuit, and the other microswitch being connectable with an arc fault protection circuit. In an alternate embodiment, a common electrical contact is mounted on the button member, and a pair of contacts are mounted on the frame, with the common contact being alternately engageable with each of the contacts mounted on the frame. The contacts mounted on the frame are connected with the ground fault and arc fault protection circuits.

Abstract: An improved test button assembly for use in a circuit breaker includes a frame and a button member, with the button member being pivotably mounted on the frame. A pair of microswitches are mounted on a printed circuit board that is disposed on the frame. The button member is alternately engageable with the two microswitches, with one of the microswitches being connectable with a ground fault protection circuit, and the other microswitch being connectable with an arc fault protection circuit. In an alternate embodiment, a common electrical contact is mounted on the button member, and a pair of contacts are mounted on the frame, with the common contact being alternately engageable with each of the contacts mounted on the frame. The contacts mounted on the frame are connected with the ground fault and arc fault protection circuits.

Abstract: A front mounting plate with integral locking tab for mounting an electrical switch to a support and for locking an operating handle of the electrical switch in a selected position. The front mounting plate includes a body having a cutout portion through which the operating handle of the electrical switch extends. The locking tab extends generally upwardly from the body and is positioned adjacent the cut-out portion and the operating handle so that a conventional padlock may be inserted through a lock receiving aperture of the locking tab to resist movement of the operating handle. The body of the front mounting plate includes first and second side projections and first and second end projections extending generally downwardly therefrom and overlays a raised escutcheon formed on a front surface of the electrical switch.

Abstract: A miniature molded case circuit breaker is adapted for use with load conductors having ring lug terminations by extending the circuit breaker load terminal conductor through the terminal recess and beyond the molded housing. An adapter includes an insulative shield member having an open slot in which the load terminal conductor terminates for connection to the ring lug on a load conductor. The adapter further includes an insulator which seats snugly in the terminal recess of the housing and through which the load terminal conductor extends. A bifurcated neck on the insulator extends through an opening into the shield member. The shield member is secured to the circuit breaker by projections which snap into grooves in the neck portion of the insulator and a cantilevered resilient finger which engages a catch on the molded housing.

Abstract: An auxiliary switch, mounted in a compartment in the molded housing of a circuit breaker separate from the compartment in which the circuit breaker mechanism is mounted, is actuated, when the circuit breaker contacts are open, by cascaded actuating members, one of which engages, through a housing panel dividing the compartments, the latchable cradle of the circuit breaker mechanism to actuate the auxiliary switch when the circuit breaker is tripped, and the second of which is spring biased against a cam surface on an operating member incorporating the circuit breaker handle to actuate the auxiliary switch when the handle is in the off position.