Abstract: A manually rotatable latch of a control unit has an oblong cross-section shalt extending through a keyhole slot in a slider, the wide dimension of the shaft being greater than the narrow portion of the slider, to block movement of the slider when the latch is extended to lock the unit to the cabinet or block insertion of the unit to the cabinet. A link from the slider extends into the path of movement of an operator to block movement of the operator to an ON position of switching apparatus of the control unit when the latch is extended. The link takes advantage of optimal latch location substantially centered in the control unit to minimize twisting of the unit within the cabinet when removal is attempted without releasing the latch.

Abstract: A plate pivotally mounted to a padlock hasp adjacent a reciprocally movable operator handle is pivotable from a stored position to one covering the opening of the hasp, the plate having a hole aligned with the opening and smaller than the opening to receive the shackle of a single, scissors-type safety lockout and maintain the shackle in position to block movement of the operator handle to an operated position. The hole is preferably rectangular to conform to the flat, thin shape of the safety lockout shackle to maintain the shackle properly oriented. An additional round hole for a smaller diameter padlock shackle may be provided in said plate.

Abstract: A drive lever of an auxiliary handle operator is pivotally mounted alongside a molded case circuit breaker to move in a plane parallel with a plane of movement of a constituent handle of the circuit breaker. A superstructure attached to the top of the circuit breaker carries a slide disposed over the constituent handle for linear reciprocal movement. The slide has a projection which is disposed in a hollow shaft of a roller bearing structure carried by the drive lever for limited translation perpendicular to slide movement with a limited amount of free play between the corresponding parts.

Abstract: A molded insulating housing is received in a slot in a rear panel of a removable control unit to extend on front and rear sides of the panel. Solid bus conductors mounted in the housing have their opposite ends disposed within front and rear openings in the housing. Plug-in connector clips are affixed to the solid bus conductors adjacent the rear openings for plug-in connection with control center vertical bus bars. The solid bus conductors are afforded limited transverse sliding movement within the housing relative to the vertical bus bars for self-alignment of the plug-in connector clips with the bus bars. Bolted connection of the solid bus conductors to control apparatus is effected at the front of the control unit using a solid preformed connector strap.

Abstract: A lever pivotally mounted on a forward brace of a removable control unit abuts a pin on the cabinet for limiting direct insertion of the unit to a depth insufficient to effect electrical engagement of plug-in connectors of the unit with bus bars in a motor control cabinet, such engagement requiring subsequent pivotal movement of the lever which automatically latches the unit in the cabinet. A compound movement of the lever is required to release the latch and separate the plug-in connectors from the bus bar. A detent structure maintains the lever in a first position for inserting the control unit into the cabinet and padlocking provisions are provided to insure the lever remain in that position when desired, thereby blocking full insertion of the control unit into the cabinet.

Abstract: A handle (52) is guided for linear sliding movement within a housing (38) mounted to the front of a removable control unit (16) and has a hinged connection (52c,64) with the forward end of a drive lever (60) which is pivotally mounted (62) within the control unit and linked (68,72) to circuit interrupting apparatus (26) mounted in the control unit for reducing the handle throw necessary to operate the apparatus. A slide bar (84) is spring biased (86) to an extended position with the operator in the ON position to engage a fixed structure (92) of the cabinet to prevent withdrawal or insertion of the control unit when the apparatus is in an ON condition. The slide bar is driven to a retracted position by the handle (52d,88) when moved to the OFF position. A handle locking plate (94) is lockable in a position of interference with the handle to prevent movement from OFF to ON positions, and has a breakaway tab (94f) removable to permit locking the handle against movement from ON to OFF.

Abstract: A molded cover control station having transverse upper and lower grooves spaced apart by a distance less than the vertical dimension of a panel opening has a resilient gasket positioned against a rear flange, the gasket having a resilient protrusion which is received within the lower groove. Insertion of the control station housing from the rear of the panel such that the lower edge of the panel opening engages the resilient protrusion within the lower groove enables the resilient protrusion to be compressed an amount sufficient to enable the upper end of the housing to be swung forwardly through the opening to align the upper groove with an upper edge of the panel opening.

Abstract: An L-shaped member (20) is secured adjacent a fuse clip (12) to extend forwardly along one side of a fuse (F) received in that fuse clip. A flexible insulating strap (24) is secured to the outer end of the forwardly projecting post (20a) to lie within a groove (20e) in the post and extend rearwardly around the back side of the fuse and then forwardly along an opposite lateral side of the fuse. Pulling the free end of the strap (24) upwardly or forwardly causes that end of the fuse to be rolled forwardly of the fuse clip with a mechanical advantage.

Abstract: An operating mechanism for an enclosed circuit breaker is disclosed and comprises: a frame mounted within an enclosure; a linearly reciprocal handle slidably mounted to the frame for operating a circuit breaker within the enclosure and extending through an aperture in a door of the enclosure; and a latch pivotally mounted to the frame and cooperating with the handle and a catch on the door to perform interlocking functions whereby the door cannot be opened unless the handle is in an "off" position and whereby the handle cannot be moved to an "on" position unless the door is closed. A defeater is provided for manually pivoting the latch to defeat its interlocking functions.