Abstract: A solenoid operated remote resetting device with a protective solenoid activation circuit is disclosed. The device includes a housing for enclosing and protecting a solenoid with a movable plunger, a movable mechanical operator having an operator arm extending through an opening defined in the housing and a circuit board on which a solenoid activation circuit is mounted. The solenoid activation circuit includes circuitry for protecting the solenoid from overheating due to intentional or unintentional prolonged current flow in the solenoid.

Abstract: The present invention provides an electrical power distribution system which contains a primary load-center (100) having a common data bus (124) that is adapted to provide two-way digital communication. A number of circuit breakers (120) are coupled to the common data bus (124). Each circuit breaker (120) has a first contact and second movable contact which is moved between a closed position and an open position by an actuator (216). The circuit breaker contains a microcontroller based control circuit (210), which controls the operation of the actuator (216) according to programmed instructions, which may be stored in a memory (234) contained in the circuit breaker or which are communicated to the circuit breaker over the common data bus (124). A status detection circuit (218) coupled to certain nodes within the circuit breaker provides status information about various contacts and current paths contained in the circuit breaker.

Abstract: An electrical isolation device for use in an electrical distribution network having a plurality of branch circuits each defined by line and neutral conductors connected between a power source and a load, the line conductor being electrically connected to one of a plurality of line buses at an electrical distribution panelboard, the neutral conductor being electrically connected to a neutral bus at the electrical distribution panelboard. The isolation device includes a filter coupled between a selected number of line buses and the neutral bus at the panelboard and is designed to provide a low impedance path for an arcing fault occurring on either of the selected number of line buses. In another embodiment, the isolation device is comprised of a filter coupled between the line and neutral conductor of a selected one of the branch circuits and is designed to provide a low impedance path for an arcing fault occurring on the line conductor of the selected branch circuit.

Abstract: A sectionalized electrical distribution feeder system for carrying electrical power from a source point to a use point or a distribution point. Each section of the distribution system includes a cylindrical enclosure capable of being easily cut with a handsaw. The enclosure also provides support and protection from physical damage to a plurality of electrical conductors that are disposed within the enclosure. The conductors are held firmly in place by a continuous electrically insulating support that snugly fits inside the enclosure. Each conductor can be easily cut with a metal cutting hand saw, and is enclosed in an electrically insulating sheath, a portion of which can be removed from a newly cut end to provide a contact surface. A joint connecting member is provided for electrically connecting the conductors of adjacent sections of the electrical distribution feeder system.

Abstract: A circuit breaker for interrupting the flow of electric current in a line includes a switch connected in series with the line, the switch having an open position and a closed position. At least one positive temperature coefficient resistivity element (PTC element) is connected in series with the line. A first magnetic coil is positioned around a yoke, for example, an iron core, and connected in parallel with the PTC element and a second magnetic coil is positioned around the yoke and connected in series with the line and the switch. A voltage limiting device, such as a metal oxide varistor, is connected in parallel with the at least one PTC element. An armature is pivotally mounted in relation to the yoke wherein the yoke and the armature form a magnetic circuit with the first magnetic coil and the second magnetic coil.

Abstract: A phase controlled weld controller system uses an internal model of weld line and load impedance and of open circuit weld input voltage to develop a nominal firing angle sequence to maintain a desired weld current sequence. The weld controller computes a nominal firing angle sequence based on estimated models of line impedance, open circuit line voltage, and an estimated relation between the load current and conduction angle and the mathematical relation between firing angle, conduction angle and load circuit power that will achieve a desired weld sequence if the models are accurate. The weld controller subsequently uses measured values received in real time while the weld sequence is being executed to modify the nominal firing angle to better achieve the desired objective. This approach allows the weld controller to quickly achieve the desired weld sequence with the actual load, while permitting low feedback gains, resulting in a system that is quick and accurate in response without being overly sensitive.

Abstract: An in-depth review of a product line is conducted, including customer interviews, in order to identify customer specifications that are more complex than customer needs. Customer needs are quantified, and a reduced set of standard product configuration classes are selected so that about 80% of customer orders based on actual customer needs can be satisfied by the standard product configuration classes, and the remaining orders can be satisfied by custom design. Major components in the standard products are themselves standardized. Manufacture of the standard product is optimized for a one-day manufacturing cycle and separated from the manufacture of the custom designed product. A sales office and manufacturing plant roll-out schedule is implemented and managed by computer-based spreadsheet tools.

Abstract: A molded plastic current limiting circuit breaker includes an interrupter assembly that includes an over-molded magnet, arc stack, baffle stack, and a chamber liner in which a trip unit is described.

Abstract: A circuit breaker and method for interrupting the flow of electric current in a line includes connecting separable contacts to a conductor in the circuit. An actuating device, actuated by an activating signal, is connected to the separable contacts to effect separation of the contacts wherein the flow of electric current in the circuit is interrupted. A current sensor, such as an iron core current transformer, senses the current in the circuit to provide a first sinusoidal signal. A bridge rectifier is connected to the current sensor wherein the first sinusoidal signal is converted to a rectified signal and power is derived from the rectified signal. An interface circuit connected to the rectifying network converts the rectified signal into a second sinusoidal signal for providing the activating signal to the actuating device at a predetermined magnitude of the first sinusoidal signal. The interface circuit includes generating a sign bit indicative of the polarity of the first sinusoidal signal.

Abstract: An in-depth review of the switchboard business, including customer interviews, revealed that customer specifications were more complex than customer needs. Customer needs were quantified, and a reduced set of standard switchboard configuration classes was selected so that about 80% of customer orders based on actual customer needs could be satisfied by the standard switchboard configuration classes, and the remaining orders would be satisfied by custom designed switchboards. Major components in the standard switchboards were themselves standardized. A standard switchboard, for example, has a continuous current capacity of no more than 4000 Amps, a maximum voltage rating of 480 Vac, a short circuit current rating of no more than 200 kA, and an aluminum or copper bus. The manufacture of the standard switchboards was optimized for a one-day manufacturing cycle and separated from the manufacture of the custom designed switchboards.

Abstract: A circuit protection apparatus employs a PTC element for overload and/or short circuit protection and an arcing fault interruption arrangement. The circuit protection apparatus may be employed in a ground fault receptacle for interrupting the flow of electrical current in a line in response to any of a plurality of different types of fault conditions on the line. The circuit protection apparatus may include a set of contacts connected in series with the line, and having an open position and a closed position, a trip device coupled to the contacts, adapted to be actuated by a trip signal, to move the contacts from the closed position to the open position and an element having a positive temperature coefficient of resistivity (PTC) connected in series with the contacts. The PTC element is connected to the trip device to provide the trip signal to the device in response to overload or short circuit conditions in the line.

Abstract: An improved viewing window construction for an electrical disconnect switch 10. The improved construction of the viewing window 70 permits easier installation of the viewing window 70 while at the same time reducing the complexity of the switch cover manufacturing process, eliminating the need for a window retainer 46 and increasing the resistance to the ingress of water when subjected to a stream of water under pressure.

Abstract: A number of methods can be used for zone arc protection to detect series and/or shunt arcing faults in various electrical components and/or circuits. A differential current detector, or a di/dt based detector, may be used to detect shunt arcs, while a differential voltage detector or a zero-sequence voltage detector, is used to detect series arcs. A differential phase current detection scheme may be used for both shunt arcs and series arcs. Series arcs may also be detected using a voltage drop system or a line power loss system. Detection of arcing in joints may be monitored directly. A ground fault detector may be combined with one or more of these systems for detecting a ground fault in the circuit to be protected. Two or more of the above systems or detectors may be combined for arc monitoring and detection.

Abstract: A power conversion system is described which includes a power input for accepting a waveform at a given power level and frequency, and a power output for providing an output waveform at a second given power level. A DC to AC converter accepts a waveform based on an input wave form from the power input and converts the waveform to an AC waveform having a frequency at least approximately an order of magnatude higher than the frequency of the input waveform for application to a DC to AC converter output. An AC converter accepts the output waveform from the DC to AC converter output and provides a converted waveform from an output of the AC converter to the power output. A coupling device operates at the frequency of the converter output for coupling the output of the DC to AC converter to the AC converter.

Abstract: A dual power source retrofit kit for a single power source service entrance panel. The retrofit kit is a field installable kit for retrofitting a single power source service entrance panel to a dual power source service entrance panel. The kit includes a power source selection assembly and a mounting bracket for attaching to the service entrance panel. A deadfront trim plate having a cut-out to accept the power source selection assembly is also supplied to replace the old trim plate of the service entrance panel. The power source selection assembly permits only the selected one of the primary or auxiliary power sources to provide power to the service entrance panel at any one time. The power source selection assembly is also designed such that overload protection devices/disconnect switches for both the primary power source and the auxiliary power source must be in the OFF position before switching from one power source to the other is permitted.

Abstract: An operating shaft which provides compensation for axial and spatial misalignment between a rotatable component mounted within an enclosure and a rotating apparatus generally outside the enclosure is disclosed. The operating shaft has a first end dimensioned to be slidably received within a receiving portion of the rotating apparatus such that the shaft is maintained in a fixed angular position with respect to the rotating apparatus. The shaft is axially slidable with respect to the rotating apparatus such that it will provide compensation for axial misalignment between the rotatable component and the rotating apparatus. The shaft has a second end configured to engage the rotatable component such that rotation of the rotating apparatus will produce a corresponding rotation of the rotatable component. The shaft also has a spatial compensation device which is integrally formed from the shaft between the first and second ends.

Abstract: A circuit protection apparatus includes a circuit breaker coupled in series with a circuit to be protected. The circuit breaker has a trip input and is responsive to a trip signal at the trip input for changing from a closed circuit condition to an open circuit condition to thereby remove electrical current from the circuit to be protected. A thermal trip element is coupled in series with the circuit to be protected and is responsive to a predetermined current/time characteristic of current flow in the circuit for delivering the trip signal through the thermal trip element to the trip input.

Abstract: A multiplex extender 26 for permitting discrete I/O devices 34, not individually equipped to decode multiplex channel addresses, to be multiplexed on a time division multiplexed control bus 10. The multiplex extender 26 is connected intermediate the time division multiplexed control bus 10 and a branch line 30 and includes a multiplex channel address decoder 78, a data disconnect switch 82 and a branch line controller 90. The multiplex channel address decoder 78 is selectively programmed to one of the multiplex channel addresses of the time division multiplexed control bus 10. The multiplex channel address decoder 78 produces one or more output signals, each being determined by the multiplex channel address which has most recently been decoded.

Abstract: A circuit for initiating the setting of a series brake upon detecting a loss of armature current in an overhauling DC crane motor. The circuit includes an ammeter shunt, a meter relay and associated contact, a meter relay power supply, a control relay and associated contact, a low current relay and associated contact and two static timers which can be added to an existing crane operating circuit. The ammeter shunt is located electrically in series with motor armature for monitoring current flow in the armature. The meter relay is connected to the ammeter shunt such that it will operate in response to a signal from the ammeter shunt indicating that current in the motor armature has dropped below a predetermined level. The meter relay requires power for operation, this power being provided by the 24 VDC power supply.

Abstract: An operator interface unit for monitoring and controlling controllers coupled to a communications network has a common database that is accessible across the network, regardless of each controllers data structure. The operator interface unit provides an apparatus for displaying, storing, and editing data obtained from the network. Data from each controller can be accessed by the unit based upon the individual controller's data structure and type through embedded objects resident in the interface unit's operating system and program. The data can then be displayed, edited, and stored by any data entry device that is capable of executing the operator interface unit's program.