Abstract: For use in a boost converter having a main boost switch, a boost inductor, a boost diode coupled to the boost inductor and the main boost switch and a resonant, passive snubber coupled to the boost inductor and the main boost switch that limits reverse recovery currents in the boost diode during a turn-on of the main boost switch, a peak voltage clamping circuit for, and method of, reducing voltage stress on the main boost switch caused by operation of the snubber. In one embodiment, the circuit includes a blocking switch and a zener diode, coupled in series between the main boost switch and the boost diode, that cooperate to provide a conductive path from the main boost switch to an output of the boost converter for electrical currents that exceed a predetermined peak voltage value thereby to reduce the voltage stress on the main boost switch.

Abstract: An electronic trip unit for a circuit breaker having two current sensors per phase, wherein the first magnetic core current transformer is designed to monitor current in the normal and overcurrent range, and the second low-permeability core sensor is designed to produce an override trip signal at or below the short time withstand current rating of the circuit breaker. In a second embodiment the electronic trip unit includes only the low-permeability core sensor that has negligible output in the normal current range.

Abstract: A surge protection circuit provides multiple stages of protection for an electronic circuit having semiconductor components from damage due to passage of excessive amount of current during a line borne voltage surge. In particular, this circuit can protect any relay load switching device that requires an electronic control circuit. The circuit of the invention achieves performance superior to that of conventional surge protectors, such as those employing metal oxide varistors, by employing an expulsion arrester as the last stage of a multi-stage protection technique against voltage surges on power lines. Low impedance electrical paths parallel to the expulsion arrester and to the electronic circuitry provide protection before the arrester switches. One embodiment employs a zener diode and a silicon controlled rectifier to provide two such parallel electrical paths.

Abstract: A method and apparatus for monitoring multi-phase alternating current signals and providing a signal representative of each phase current signal. Each alternating current signal is rectified by a direct current output rectifier to generate a signal representative of both the phase and magnitude of the alternating current signal. The method and apparatus also provides for using the output signal to operate a circuit breaker in a ground fault detection system.

Abstract: The preferred embodiment apparatus employs an interior trim panel and an electrical harness for use in an automotive vehicle. In one aspect of the present invention, the interior trim panel has a generally rigid substrate covered by an aesthetically pleasing covering material. In another aspect of the present invention, an electrical harness is provided with integrally created switch contacts and integrally created connector terminals.

Abstract: An over voltage cut-off circuit of a private branch exchange for cutting off the over voltage induced into an E&M (ear and mouth) tie line, includes an E ("ear") line over voltage cut-off circuit composed of an E arrestor which generates heat by the over voltage induced through the E port, and also of an E fuse which melts and blows if it surpasses a melting point. The circuit may also include an M ("mouth") line over voltage cut-off circuit.

Abstract: An electric device is provided as an interface between a permanent power source (e.g., an electric wall outlet) and an electrical appliance. The device operates to interrupt electrical power to the electrical appliance in response to an increase in temperature of either the power cord plug of the electrical appliance or the terminals of the permanent power source to a predetermined temperature. The electric device detachably couples to the electric power terminals of both the permanent power source and the electrical appliance and is sensitive to the temperature at the terminals. The device includes a thermostat which rests on a thermal barrier member in thermal communication with the terminals, and is responsive to heat generated at the terminals to interrupt electrical power from the permanent power source to the appliance.

Abstract: Cable interconnection apparatus for connecting coaxial cable and fiber optic cable, the cable interconnection apparatus being adapted to be removably mounted in network interface devices containing subscriber bridge modules.

Abstract: A novel current-limiting line protector for a communications circuit is disclosed, and includes a first and second incoming conductive member, a one piece roll-formed conductive member conductively coupled to each incoming conductive member, a ground member, an S-shaped spring in slidable contact with the ground member, and a first and second diode and solder member combination conductively coupled to the first and second incoming conductive members and disposed between the spring and the incoming conductive members. Each diode and solder member combination maintains the spring and the respective incoming conductive member in spaced, non-conducting relation while each solder member remains substantially intact.

Abstract: An electrostatic discharge circuit comprising a static discharge input node, a first NMOS FET having its drain connected to the input node and its source and substrate connected to Vss, a first CMOS inverter comprised of a first PMOS FET and a second NMOS FET having the source and substrate of the first PMOS FET connected to the input node, the drain of the first PMOS FET connected at a junction to the drain of the second NMOS FET, and the source of the second NMOS FET connected to Vss, and the gates of the first PMOS FET and of the second NMOS FET connected to Vdd and the junction connected to the gate of the first NMOS FET.

Abstract: The present invention relates to a passive electronic component architecture employed in conjunction with various dielectric and combinations of dielectric materials to provide a differential and common mode filter for the suppression of electromagnetic emissions and surge protection. The architecture allows single or multiple components to be assembled within a single package such as an integrated circuit or connector. The component's architecture is dielectric independent and provides for integration of various electrical characteristics within a single component to perform the functions of filtering, fusing and surge suppression, alone or in combination.

Abstract: A backup gap type over-voltage protector and thermal protector for a two element gas discharge tube. The gas discharge tube is mounted with its electrodes between opposing fingers of a clip of electrically conductive material. One of the clip fingers contacts the tube electrode that is to be grounded and the other finger is spaced from the other tube electrode that receives the voltage by a piece of thermally meltable, electrically insulating material having at least one hole that is located under the finger. Upon failure of the gas discharge tube, an over-voltage applied to the electrode jumps the gap formed by the hole in the insulating piece back to the clip finger and is conducted to ground. Upon thermal overload of the gas discharge tube, the insulating piece melts and brings the clip finger into contact with the tube electrode receiving the voltage and connects it and the voltage line to ground.

Abstract: A gas tube protector module is provided that provides sneak current protection in addition to voltage surge protection. The module has two pairs of terminals with one pair for connection to outside plant and the second pair for connection to the inside wiring. The module has a gas tube with leads connected to the first pair of terminals. Positive temperature coefficient (PTC) resistors are disposed electrically between the lead and the second pair of terminals such that the PTCs are in series between the outside plant and the inside wiring.

Abstract: Electrostatic discharge protection circuits adapted for use in low voltage CMOS processes have at least one PFET in the primary charge conduction path, and timer circuits configured to enable the primary conduction path during ESD events and to disable the primary conduction path during steady state conditions.In a further aspect of the present invention, bias circuits for maintaining steady state gate voltages below the dielectric breakdown level are included.In a still further aspect of the present invention a bridge circuit couples a first power supply node to a second power supply node, where the second power supply node is coupled to an ESD protection circuit.

Abstract: An output driver which maintains over voltage protection on individual circuit elements, providing either a level shifted logic high or a floating-state on its output. The output driver includes a latch driven by a set circuit and a reset circuit. The latch output drives an output stage which produces a level shifted logic high when the latch is set and a floating-state when the latch is reset. Minimal voltage is applied across individual circuit elements by supplying power in concurrent incremental voltage levels to the output driver.

Abstract: An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard.

Abstract: Motor protection for air conditioning and refrigeration compressors includes in a first embodiment a cluster block (22) having a seat for a hermetic motor protector (24, 24') and mounting a combination terminal/fusible link (26/26d, 26d') in which the motor protector and combination terminal/fusible link can be exposed to cooling fluid contained in the compressor container and the cluster block is mounted on a lead-through pin (18a) of a header (18) in the container wall. In a second embodiment the cluster block (30) is mounted on all three pins (18a, 18b, 18c) of header (18) with pin connectors received in parallel extending channels (30a, 30b, 30c) of the cluster block. In another embodiment the cluster block (40) is irregular in configuration in order to accommodate available space in certain compressor containers and has a lid (40g) to enclose the motor protector.

Abstract: A control circuit for providing fast turn-off of a PNP transistor with output transient protection. An embodiment of the invention provides a current amplifier coupled between a positive voltage supply line and the base of a PNP switching transistor and an input device for providing an input current to the current amplifier. The current amplifier provides a transitory reverse drive current to the base of the PNP switching transistor. The current amplifier and the input device both include transient blocking junctions that block current flow from a positive voltage transient in excess of the positive supply voltage. The current amplifier is a PNP drive transistor in the preferred embodiment. The PNP drive transistor provides a transitory reverse drive current to the base of the PNP switching transistor.

Abstract: A circuit breaker includes a current path for first and second contacts connected in series in an insulative container. When an overcurrent occurs by over load, the second contact is opened based on a command from a time delay trip portion of an overcurrent trip device. When a short-circuit current occurs, the first and second contacts are opened based on a command from an instantaneous trip portion of the overcurrent trip device. Since the first and second contacts are contained in a common container, the wiring works between the first contact and the second contact is unnecessary. Since the first and second contacts are opened in the instantaneous trip, interruption of a high short-circuit current is facilitated.

Abstract: A circuit recloser that limits current through a power line when a fault condition occurs. The recloser includes a circuit interrupter that is switchable between a closed state, in which current is permitted to flow through the power line, and an open state, in which the current is interrupted. The interrupter switches to its open state in response to a fault condition, such as a current surge. The recloser also has a movable member that is operatively coupled to the interrupter for resetting the interrupter to the closed state from the open state when the movable member is moved. The movable member is configured for being remotely movable to close the interrupter. Preferably the recloser includes an electric drive to remotely move the movable member from a remote station, and a projection extends from the movable member to enable manual movement thereof. The movable member includes a shaft which the electric drive rotates by turning a slotted hub coaxially about the shaft.