Abstract: An arc fault detector system detects arcing faults in an electrical distribution system by monitoring one or more conductors and producing an input signal representing one or more electrical signal conditions in the circuit to be monitored. This input signal is processed to develop signals representing the electrical current flow through the monitored circuit and broadband noise signal components. The system analyzes these signals to determine whether an arcing fault is present, and if so, outputs a trip signal which may be used directly or indirectly to trip a circuit breaker or other circuit interruption device.

Abstract: A sensor system is disclosed. The system comprises a sensor for sensing an input between a first, minimum sensor input value and a second, maximum sensor input value. The sensor generates a sensor output signal relative to the sensor input value. The sensor is subject to offset and gain errors. The system further includes a microprocessor having first and second output signals and a signal conditioner coupled between the sensor and the microprocessor. The signal conditioner generates a first signal conditioner signal when the sensor input value equals the minimum sensor input value and generates a maximum signal conditioner signal when the sensor input value equals the maximum sensor input value. The signal conditioner includes circuitry for minimizing the sensor offset error and circuitry for minimizing the sensor gain error.

Abstract: An electrical fault detector system detects electrical faults in an electrical distribution system by monitoring one or more conductors and producing an input signal representing one or more electrical signal conditions in the circuit to be monitored. This input signal is processed to develop a first signal representing the electrical current flow through the monitored circuit and a second signal representing signal components in a selected frequency range typical of arcing faults, and which exceed a predetermined threshold. The system also detects ground faults in the circuit being monitored.

Abstract: An apparatus for use in arcing fault detection systems within circuit breakers and which is adapted for automated production by top-down assembly. In one embodiment, the apparatus includes a circuit board and a two-piece sensing coil within a two piece housing with its center oriented horizontally relative to the circuit board. In other embodiments the sensing coil is one-piece and is either preassembled with a sensing bus and oriented horizontally or oriented vertically relative to the circuit board. Also included are several methods for making electrical connections to the circuit breakers.

Abstract: A circuit breaker unit having a backmold which can withstand horizontal axial forces, which cause deflection or bowing of the backmold. The circuit breaker unit comprises an enclosure, cradle and pultruded backmold. The pultruded backmold is molded with at least one horizontal rib adjacent a top end, a bottom end or an area therebetween to provide additional strength and support of the circuit breaker and field serviceable connections.

Abstract: An expandable transformer housing having a first housing member with a hollow cavity therein, a second housing member with a hollow cavity therein, and at least one exterior insert member therebetween in a stacked formation. The exterior insert member has a first end and a second end. A portion of the first end of the exterior insert member is adapted to engage the first housing member and a portion of the second end of the insert member is adapted to engage the second housing member. An interior insert member is also provided having a first end and a second end. A portion of the first end of the interior insert member is similarly adapted to engage the first housing member and a portion of the second end of the interior insert member is adapted to engage the second housing member. The interior insert provides insulation between the current source and the second windings of the transformer.

Abstract: A communications adapter is provided for interfacing between a master device and an I/O device (body) having an output and/or an input. In the case of the I/O body having an output, the adapter has a TCP port for coupling to the master device via a transmission path for receiving a request message. The adapter also has a connector for operable coupling to the I/O device for receiving the output of the I/O device. The adapter further has an interface circuit operably connected to the TCP port and the connector for transmitting a response message over the transmission path in response to the request message, the response message correlating to the output received from the I/O device. The request message and the response message is limited to a length that is less than a TCP transaction length and/or a maximum transmission unit limit, or both, depending on the embodiment of the present invention.

Abstract: An arcing fault circuit interrupter testing method includes the steps of producing a simulated line to neutral arcing fault signal comprising a relatively large di/dt signal, applying the signal to a branch circuit, and producing an observable indication of operation or lack of operation of an arcing fault circuit interrupter in the branch circuit in response to the simulated line to neutral arcing fault signal. A test apparatus carries out the method.

Abstract: The present invention provides an accessory module for monitoring and controlling the status of a circuit breaker. The accessory module attaches to the side of a circuit breaker and has a mechanism similar to the mechanism in a circuit breaker. The mechanism has multiple positions that correspond to multiple states of a circuit breaker. Actuators transform relatively large-scale motions of the mechanism into small-scale motions and transfers these to buttons on switches. Depressing these switches depending on the position of the mechanical assembly makes and breaks circuits that are in communication with a remote site. The invention provides a circuit board designed specifically to hold and locate the switches and actuators and provide tracings that can withstand high currents. The invention further provides a terminal plug having a pull tab which can be grasped to remove an otherwise inaccessible terminal plug.

Abstract: A magnetic core assembly and method of assembling a magnetic core assembly. The core assembly includes laminated magnetic core tightly clamped together by a pair of unitized flanged clamps. Each unitized flanged clamp has a generally flat surface and a peripheral flange. The generally flat surface defines at least one opening for receiving a coil and a number of holes adjacent the opening for receiving assembly hardware. The core is assembled by placing a first one of the two unitized flanged clamps, flange down on a generally horizontal work surface. Alignment pins are placed in one or more of the assembly hardware apertures adjacent the coil opening. The segments of the first core lamination are slidably placed on the alignment pins such that they lie on the flat surface of the first unitized flange clamp. The segments of each remaining core lamination are slidably placed on the alignment pins until the required number of laminations have been installed.

Abstract: A switchboard for mounting and supplying electrical power to a plurality of circuit breakers has all the breakers are mounted on one side of a vertical power stack. The power stack has vertical buses to which the breakers are connected. Insulators and spacers provide air ventilation paths through the power stack. The main bus connecting members on the other side of the power stack from the breakers and are spaced apart vertically to allow for improved heat dissipation. By using vertical bus connectors, the bus connecting members may be connected to through bus connectors at any height on the back of the switchboard. The main bus connecting members are in a vertical chimney for improved heat dissipation. The circuit breaker at the highest location (the “A” phase) has the highest temperature and in the present invention, the main bus connecting member for the A phase is in the highest position to place it closest to the heat source and thereby improve the heat conduction away from the breakers.

Abstract: A system to detect arcing faults in an electrical distribution system with a line conductor connected to a utility power transformer. The system monitors the rate of change of electrical current in the line conductor and produces a signal which represents the rate of change. The system produces a pulse each time the rate-of-change signal exceeds a selected threshold, filters the rate-of-change signal and/or the pulses to substantially eliminate a signal or pulse which represents changes in the electrical current outside a selected frequency range, monitors the remaining pulses to detect when the number of pulses that occur within a selected time interval exceeds a predetermined threshold, and generates an arc-fault-detection signal in response to the occurrence of a number of pulses which exceed the threshold within the selected time interval.

Abstract: A linkage assembly for a double throw safety switch including a frame connected to a first slider plate and a second slider plate. The first and second slider plates are moveably connected to the frame by guides in the form of slots which cooperate with slider supports on the frame. The profile of the slots define a range of movement of the slider plates. A driver arm is used to effect simultaneous movement of the slider plates either toward or away from a central portion of the driver arm. A first follower arm which controls a first single throw switch, and a second follower arm which controls a second single throw switch, are also connected to the frame by a spline coupling. The first follower arm includes a slider support which cooperates with a guide, again a slot, in the first slider plate. Similarly, the second follower arm includes a slider support which cooperates with a guide in the second slider plate.

Abstract: The present invention relates to a transformer having a conductive element spiraling along the length of an insulated wire of the coil. When formed into plurality of adjacent turns, the conductive element couples one of the plurality of turns with another of the plurality of turns. The conductive element increases the series capacitance of the transformer circuit. A resistive element may also spiral along the length of the insulated wire to couple one of the plurality of turns with another of the plurality of turns. The resistive element not only increases the series capacitance of the transformer, but also increases the series conductance of the transformer circuit. The increase in the series resistance increases the dampening of the switching resonance.

Abstract: A protective containment apparatus for preventing damage to expensive components of an assembly due to the failure of an electronic component in a nearby potted circuit which is known to fail catastrophically. The containment apparatus can employ a resilient material 38 placed around the at-risk electronic component 34 prior to potting the circuit. The resilient material 38 absorbs the expanding gases and fragmented parts of the at-risk component 34 which are expelled during the catastrophic failure. The cushioning effect of the resilient material 38 prevents the fragments and parts of the potting material from becoming projectiles that can damage any nearby components of the assembly. The containment apparatus can also employ a restrictive material 42 placed around the at-risk component 34 prior to potting the circuit.

Abstract: An assembly for auotomatically mating a plug terminal attached to the exterior of a circuit breaker with a receptacle terminal attached to the interior of a switchgear cell to provide secondary connections therebetween. The assembly includes a plug having a generally planar body partially defined by a surface and opposing surface. A plug terminal is supported by the opposing surface of the plug. A mounting bracket is slidably affixed to the opposing surface of the plug. The bracket has an aperture to allow the plug terminal to extend therethrough. The bracket is secured in a fixed position to the exterior of the circuit breaker. The position of the plug is automatically adjusted to provide proper alignment between the plug terminal and the receptacle terminal to form an electrical connection between the terminals which can be disengaged.

Abstract: A weatherproof enclosure 10 with a side hinged cover 36 having a screwless cover latching means 52, which is not defeated by the pressure of expanding internal gases, is disclosed. The enclosure 10 includes a rain channel 76 located immediately adjacent a front edge of the box top 28. The rain channel 76 is generally J-shaped in cross-section and extends across the front of the box 14 and slightly beyond the two side walls 18 and 22 of the box 14 such that any liquid being received within the rain channel 76 will be directed over the side walls 18 and 22 of the box 14. The rain channel 76 cooperates with a downwardly extending flange 40 along the front edge of the box top 28 and an inwardly extending flange 60 along the top of the side hinged cover 36 to prevent the ingress of liquid at the top of the cover 36. Inwardly facing flanges 68 and 72 along the sides of the hinged cover 36 overlap the side walls 18 and 22 of the box 14 to prevent the ingress of liquid along each side of the cover 36.

Abstract: A remotely operable switch actuation module for retrofitting a manually operated disconnect switch. The switch actuation module includes a linear operator which produces a linear movement in response to an external signal and a mechanical interface shaft which translates the linear movement into rotational movement required by the switch operating mechanism to change the ON or OFF state of the disconnect switch. The ends of the mechanical interface shaft are provided with engagement means complementary to the engagement means provide on switch operating mechanism pivot shaft and the operating arm of the manually operated disconnect switch. Therefore, the mechanical interface permits the switch operating mechanism to be engaged by either the remote switch actuation module or the manual operating arm. The switch actuation module also includes a switch status indicator which produces an electric signal indicating the ON or OFF state of the disconnect switch.

Abstract: The present invention provides a device for electrically connecting electrical conductors of two adjacent sections of a multi-phase electrical distribution system. The connecting device includes a generally cylindrical body enclosing two ground connectors, two outside insulators and two inside insulators intermediate the outside insulators. Each of the outside and inside insulators includes an equal number of semi-circular shaped electrical connectors which are arranged such that each electrical connector on one of the outside insulators has a corresponding electrical connector on one of the inside insulators thus forming a pocket. Each pocket receives one electrical conductor from each of the two adjacent sections of the electrical distribution system.