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: An arcing fault protection assembly and a corresponding method determine whether arcing is present in electrical circuits. The assembly powers-up quickly without dissipating excessive heat while power is being supplied to the assembly. The assembly comprises a sensor, a broadband noise circuit, a controller, and a dual-mode power supply. The sensor detects a current flowing in an electrical circuit and develops a corresponding sensor signal. The broadband noise circuit determines the presence of broadband noise in the sensor signal and produces a corresponding output signal. The controller processes the sensor signal and the output signal in a predetermined fashion to determine whether an arcing fault is present in the circuit. The dual-mode power supply supplies power to the sensor, broadband noise circuit and controller using a first mode and later switching to a second mode. The first mode reaches steady state faster than the second mode.

Abstract: A method for time reference compensation in a power metering system, the method comprising monitoring a time-dependent characteristic of incoming AC power over a predetermined local time interval, comparing the monitored characteristic over the predetermined local time interval with the expected value of the characteristic based upon the nominal frequency of the AC power, and calculating a correction to one or more of local real-time and time-based measurements of the power metering system, based on the comparing.

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: The device compares a voltage representative of the supply voltage of the electromagnet with two distinct inrush thresholds and a drop-out threshold. As soon as this voltage reaches one of the inrush thresholds, the device commands switching to an inrush phase of preset duration. The first inrush threshold is representative of a voltage of about 40 to 50% of the rated supply voltage of the electromagnet, whereas the second inrush threshold is representative of 70 to 85% of this voltage. The same control device can thus be used with both an under-voltage release and a shunt release or for a circuit breaker closing electromagnet.

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: A metering module has a housing, a metering circuit in the housing for receiving and processing at least one signal corresponding to an electrical quantity, and developing an output signal. A connector mounted to the said housing is coupled to the metering circuit, and configured for engagement with a mating connector at least one of a sensor array module and a mounting and connection base. Mounting structure is provided on the housing for removably mounting the housing to at least one of a sensor array module and a mounting and connection base. A circuit in the housing delivers voltage and current signals received at the first and second connectors to a further connector mounted on the housing. First and second mounting structures are provided for mounting the housing to a surface and for mounting a removable metering module.

Abstract: An apparatus for use in arcing fault detection systems within circuit breakers and which is adapted for automated production by top-down assembly. The invention also includes several devices for making electrical connections to the circuit breakers, including a lug having a top and a hollow center, the top having a hole connecting the top to the hollow center for accessing a wirebinding screw, a neutral bus having a first end and a second end, the first end disposed within the hollow center beneath the hole, a wire binding screw disposed in the hole and extending through the hollow center for securing a first wire to the first end of the neutral bus, and a strain relief member connected to the second end of the neutral bus for securing a second wire connected to the second end of the neutral bus.

Abstract: A system for determining whether arcing is present in an electrical circuit includes a sensor for monitoring a current waveform in the electrical circuit, and an arc fault detection circuit which determines whether an arc fault is present in response to the sensor. The arc fault detection circuit includes a controller which produces a trip signal in response to a determination that an arcing fault is present in the electrical circuit, and an inhibit/blocking function for preventing the production of the trip signal under one or more predetermined conditions.

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: An arc fault circuit interrupter system for use with an electrical circuit includes an arcing fault detector which monitors the electrical circuit and a controller which generates a trip signal in response to the detection of arcing faults. The controller may also generate one or more communication signals corresponding to information relating to the operation of the arcing fault circuit interrupter. The system may also include one or more of the following: a communication port which communicates to a user the information relating to operation of the arc fault circuit interrupter in response to the communication signals; a memory for retaining predetermined information related to the condition and operation of the arcing fault circuit interrupter, with or without a backup memory; and a combined self-test/reset switch.

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 apparatus for detecting arcing faults in an electrical distribution system including a plurality of phase lines for connecting a power source to a respective plurality of loads and one or more current transformers electrically coupled to a selected number of the phase lines. Each of the current transformers have a secondary line extending therefrom and carry an electrical current. The arcing fault detection system comprises a sensor coupled to at least one of the secondary lines for monitoring the rate-of-change of current or voltage associated with the secondary line and producing a signal representing the rate-of-change. An arcing fault detector circuit evaluates the sensor signal for characteristics representative of arcing faults. If an arcing fault is detected, the arcing fault detector circuit triggers a line interrupter to disconnect the load from the power source in the phase line associated with the secondary line.

Abstract: A method for calculating a first and second gain for a controller circuit for a plant is disclosed. The method comprises the steps of providing a reference model circuit with desired circuit characteristics, providing a reference model adaptive circuit, setting the second gain to zero, supplying a spectrally rich input signal to the reference model and to the controller circuit, determining the first gain by continuously adjusting the first gain until an output of the reference model and an output of the controller circuit are substantially equal, setting the first gain to the previously determined value, determining the second gain by continuously adjusting the second gain until an output of the reference model and an output of the controller circuit are substantially equal and setting the second gain to the previously determined value.

Abstract: A remote metering display is used for displaying power-related information generated by a power meter linked to the display. The remote metering display comprises a display screen, a plurality of user interface buttons for navigating through menu options depicted on the display screen, and a motion sensor for activating the display screen in response to detection of a person's presence within a predetermined distance of the motion sensor.

Abstract: An improved connector comprises a circuit breaker terminal having a cold formed, countersink aperture on a top surface of the breaker terminal and an extruded raised ring on the bottom surface of the breaker terminal. The wire connector is a square-shaped element having a plurality of openings for receipt of at least one wire, the circuit breaker terminal and the wire connector shoe. In assembly of the three piece connector, the circuit breaker terminal is inserted into an opening in the wire connector. The wire connector shoe is then inserted into at least one opening in the wire connector and surrounds a portion of the circuit breaker terminal within the wire connector. The wire connector shoe has a protrusion, which is cold formed by displacing shoe material into the countersink aperture on the top surface of the circuit breaker terminal.

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: An earth protection device having an input for receiving a first signal representative of an earth fault current, a first signal processing module, and a module for processing protection functions connected to the first signal processing module. The device includes a second signal processing module connected between the input and the first signal processing module for processing the first signal representative of the earth fault current and for supplying to the first signal processing module a second signal representative of the earth fault current. In order to increase the value of the second signal over an RMS value when the fault current comprises pulses of short duration, the second signal has, at decreasing second signal values, a gradient lower than a preset gradient limiting value.

Abstract: The present invention provides a current limiting circuit breaker having a plurality of current responsive devices for opening a pair of contacts upon short circuit conditions. One such device is a conventional magnetic tripping mechanism. The other device utilizes an insulating object driven by a magnetic force caused by the short circuit current. Upon opening of the contacts with the use of the insulating object, let-through current flows through a secondary contact, positioned on the insulating object, to a positive temperature coefficient resistivity element which limits the current and arcing in the contacts. In an alternative embodiment, at least one steel component is added to increase the magnetic force, thereby providing a greater force on the insulating object. An insulation component is also added to further suppress any arc generated between the contacts when going from a closed state to an open state.