Abstract: An anti-rotation device for preventing the pivotal rotation of a circuit breaker required for removal of that circuit breaker from electrical distribution equipment in which it is installed is disclosed.

Abstract: A medium voltage controller for electrical equipment, such as motors, transformers, reactors, and capacitors, having a load discharge device. The load discharge device is compact and provides fast earthing of the load-side cables. The device has a scissors-type linkage and is charged by compressing at least one spring. The scissors-linkage, when in an almost-straight-line alignment, holds the compressed springs. An actuator moves one member of the scissors-linkage, thereby removing the holding alignment of the scissors-linkage. The springs move an earthing bar at high acceleration to ground the line-side cables.

Abstract: An enclosure and operating handle apparatus for a double throw switch is disclosed. An operating handle support defines two distinct switch compartments within the enclosure and supports an operating handle apparatus configured for selectively operating only one of two switches inside the enclosure at a time.

Abstract: A method of rapidly dissipating energy from a contactor controlled by a switching device, the steps comprising: operably connecting a metal oxide varistor to the switching device; interrupting electrical current to the contactor; absorbing energy from the contactor; and, limiting the amount of voltage across the switching device.

Abstract: A medium voltage controller for electrical equipment, such as motors, transformers, reactors, and capacitors, having an arc resistant cabinet, swaged internal electrical connections, a one-piece self-aligning withdrawable finger cluster, a pull-out instrument compartment, a load discharge device, cast fuse holders, disconnect switch, a switch illuminator, low power current transformers, and an optical temperature measuring system. The one-piece self-aligning withdrawable finger cluster includes a plurality of members formed to surround a mating stab for making a removable electrical connection. The throat of the finger cluster is smaller than the mating stab, and, when mated with the stab, opposing members are biased against the stab.

Abstract: A method and device for immunizing a contactor circuit from the inductive effects of a holding coil derived power supply, including: sensing a voltage signal from a power supply, the voltage signal having a switching range comprising an upper voltage and a lower voltage; providing a drive output responsive to the upper voltage; holding the drive output at a constant level as the voltage signal remains above the lower voltage; and, disabling the drive output in response to the voltage signal droppings below the lower voltage.

Abstract: A fuse base assembly for electrical fuses, including an electrical bus on which a load end fuse clip of the end-user's choice can be attached. The electrical bus is provided with means for attaching the selected load end fuse clip in a linearly adjustable manner such that the end user can adjust the spacing between the line and load end fuse clips as required for the desired fuse. The electrical bus is also provided with a load terminal attaching point such that wiring between the load device and the fuse is easily accomplished.

Abstract: An apparatus for housing and securing a switch operating mechanism. The switch mechanism housing includes a housing member with an integral pivot bushing, a housing cover, an operating mechanism including a push rod assembly, a rotor cam, and mechanism shaft. The operating mechanism is installed and fixed in the housing member. The housing member holds captive the operating mechanism without requiring that the housing cover be in place, thereby facilitating fabrication and assembly.

Abstract: A power line communications apparatus and method for providing communications over power leads connecting two pieces of electrical equipment. One power lead is split into similarly sized first and second parallel conductors. The first and second conductors pass through a current transformer, the first conductor having a load current flow opposite the second conductor with respect to the current transformer. The transmitted communications signal is applied to the secondary of the current transformer and is induced on the primary of the transformer, namely a loop formed by the first and second conductors. A second current transformer serves as a receiving transducer and senses the communications signal on the first and second conductors.

Abstract: A method for providing electrical current to a contactor circuit, by providing a power supply circuit having a power supply resistor, the power supply circuit supplies electrical current to the contactor circuit in response to the electrical specifications of the contactor; selecting a value for the power supply resistor in response to the contactor's electrical specifications and requirements of the contactor circuit; and, inserting the selected power supply resistor into the power supply circuit.

Abstract: The present invention comprises a reset mechanism for an overload relay. More particularly, the present invention comprises a mechanism that will reset a plurality of overload relay within a starter in a motor control unit. A single point-to-two point overload reset mechanism allows for the use of a single manual door reset button and extension arm to depress the single point-to-two point overload reset mechanism, which in turn depresses a plurality of overload relay reset buttons. Following contact with the overload relay reset buttons, the single point-to-two point overload reset mechanism returns to a non-contact position with respect to the overload relay reset buttons.

Abstract: A captivated slidable access cover incorporates an integral cantilevered spring to prevent undesired movement resulting from gravitational forces or vibration. The cover has two generally parallel, opposed edges which are slidingly captivated in opposed tracks of the enclosure. The integrally formed cantilevered spring is located adjacent one end of the cover and biases the cover to be in one of a positively open position or a positively closed position. The cantilevered spring presses against a portion of the enclosure at or adjacent one end of the access opening defined in the enclosure. The biased interaction between the cantilevered spring and the enclosure ensures a positive open or closed position of the cover. The cover also includes a handle at its other end for slidably opening and closing the cover.

Abstract: A medium voltage controller for electrical equipment, such as motors, transformers, reactors, and capacitors, having an arc resistant cabinet, swaged internal electrical connections, a one-piece self-aligning withdrawable finger cluster, a pull-out instrument compartment, a load discharge device, cast fuse holders, disconnect switch, a switch illuminator, low power current transformers, and an optical temperature measuring system. The pull-out instrument compartment includes a sliding rack to which a hinged instrument mounting panel is attached. The mounting panel slides out of the compartment and swings away from the opening in the cabinet, allowing access to the cabinet internals.

Abstract: A multi-level thermal management system and method are provided for cooling a plurality of vertically spaced electrical components, including a lower electrical component and an upper electrical component. The system includes a rigid support securing the upper electrical component in a fixed position above the lower electrical component. A duct, having an upper end and a lower end, an inlet defined in the lower end of the duct and an outlet defined in the upper end of the duct, is mounted adjacent to the upper electrical component with the inlet being located above the lower electrical component to direct air heated by the lower electrical component through the duct without substantially contacting the upper electrical component.

Abstract: The present invention provides a support base and neutral base for an interior assembly in an electrical distribution device and a method of assembling the same. The interior assembly having at least one bus bar and neutral bar connecting the electrical distribution device to a circuit having at least one phase. The neutral bar and bus bar having a bottom wall and side walls. The support base includes a generally planar body defining a mounting surface on one face of the body and means for mounting the bus bar on the mounting surface. The support base also includes means for retaining the bottom wall of the neutral bar abutting the mounting surface of the body. The retaining means is manually operated and integrally formed with the mounting surface and has a plurality of projections upstanding from the mounting surface. The projections are adapted to abut the side walls of the neutral bar so as to prevent movement in at least one direction horizontally.

Abstract: A sliding barrier for an electrical enclosure for selectively providing or prohibiting access to electrical conductors behind the barrier. The barrier includes upper and lower tracks and two substantially identically configured slidable panels. The panels are provided with operators for manually sliding the panels between open and closed positions. The panels are also provided with an interference interlock that inhibits unintentional opening of the panels and gapping between the panels when closed.

Abstract: A method and captive splice assembly for electrically and structurally connecting a pair of bus sections. The assembly includes a housing, which holds captive a set of splice bars. The housing has a set of captive nuts, which are engaged by a set of bolts which pass through the splice bars. During installation, the captive splice bars are held fixed in the housing by way of notches in the splice bars and protruding tangs in the housing. After installation, the splice bars are interleaved with the bars of a pair of bus sections, and the bolts compress the splice bars and sections of bus, forming an electrical and structural connection between the pair of bus sections. The housing is fabricated of either a non-magnetic metal or plastic material.

Abstract: A method for protecting a printed wiring board (PWB) and the electrical components mounted on the PWB from high temperature, fire, plasma and debris resulting from a catastrophic failure of an at-risk electronic component located on the PWB or in close proximity to the PWB. This protection is provided by a layer of inorganic refractory material applied to a surface of the PWB adjacent the at-risk electrical component. The refractory material is preferably applied to the PWB surface as a pourable liquid. The refractor material must have sufficient viscosity such as to easily flow in and around electronic components located on the PWB and be self-leveling before curing, so as to produce a uniform thickness. The refractory material should also have a small shrinkage factor when cured such that no gaps are created between the PWB and the enclosure and around the electrical terminals of the at-risk components.

Abstract: The present invention discloses an improved arc fault detection circuit comprising a light detector for generating a light detector signal, a differentiator circuit for receiving a light detector signal and creating a differentiated light detector signal, and a comparator circuit for comparing the differentiated light detector signal and a reference signal and generating a comparator output signal for indicating when the differentiated light detector signal exceeds the reference signal.

Abstract: An adjustable height spacer for providing rigid support and insulation between the bus bars of an electrical panel. The spacer is adjustable in height to provide various distances between the bus bars. The spacer includes a pair of body members that are axially aligned. A repeating series of teeth of various heights is defined around the margin of each body member at one end. The teeth are configured such that when the toothed ends of two body members having identical tooth patterns are mated, the teeth operatively engage each other to provide a secure coupling when the body member is placed under a compressive force. The height of the body member is varied by rotating one body member with respect to the cooperating body member such that a selected set of teeth within the series is engaged.