Abstract: A current induction arrangement develops a power supply voltage and a measurement signal from current flowing in a circuit path so as to optimize both the energy developed in the power supply and the fidelity of the sinusoidal signal used to measure the waveform in the circuit path. The arrangement includes a capacitor accumulating current to develop a positive voltage with respect to common, a current transformer inducing current from the circuit path and providing an output having a positive induced-current signal component and a negative induced-current signal component. A rectifier circuit is arranged to receive the output from the current transformer, and to produce the positive induced current signal component at a positive output terminal and the negative induced current signal component at a negative output terminal. A first zener diode is connected to receive the positive induced-current signal component, and the circuit permits the positive induced-current signal to charge the capacitor.

Abstract: A dry type transformer has an iron core, high voltage windings embedded in cast resin, and low voltage windings resin encapsulated. The low voltage winding is constructed with flexible sheet conductors coincident with layer insulation sheets that extend beyond the edge of the sheet conductor. Cooling air ducts are fabricated in the low voltage windings as it is wound. To prevent the extension of the layer insulation sheets from collapsing over the formed air ducts during a vacuum and pressure resin impregnation process, reinforcing means are added to the extensions to prevent them from collapsing.

Abstract: The present invention locates the primary winding of a transformer in a configuration where it substantially surrounds the secondary winding of the transformer in order to enhance the efficiency of the electromagnetic coupling. High magnetic permeability material surrounds portions of the primary winding of the transformer. The transformer is designed to efficiently operate at frequencies of approximately 50 kilohertz. In one preferred embodiment, the primary winding of the invention is formed of two U-shapes in which the parallel members of the U are substantially longer than the bottom portion of the U. The two U-shapes form a rectangular shape and the substantially parallel rectangular portions are surrounded by high magnetic permeability material to further enhance the electromagnetic coupling between the primary coil winding and the secondary coil winding. In another embodiment, the primary winding of the invention may be rectangular in shape.

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: In an electrical switching device including a stationary contact carrier having a stationary contact mounted thereon, a contact carrier assembly comprises a movable contact carrier and an arc-resistant protective shield. The movable contact carrier has a movable contact mounted thereon. The movable contact carrier is movable between a closed position and an open position. The movable contact abuts the stationary contact while the movable contact carrier is in the closed position, and the movable contact is separated from the stationary contact while the movable contact carrier is in the open position. The arc-resistant protective shield is mounted to the movable contact carrier and surrounds the movable contact. The shield protects the movable contact carrier from electrical arcs generated during circuit interruption.

Abstract: A non-ferrous current sensor is used to continuously measure the charging current magnitude in step-graded foil and paper insulation systems and capacitive insulation systems used on high voltage measurement and control apparatus such as instrument transformers and on the condenser bushings of power transformers and circuit breakers. The low voltage measured signal is conditioned by an electronic circuit such that it modulates a DC signal in a system current control loop to provide continuous remote monitoring and alarm functions. Remote power is supplied to the sensor and conversion circuits through the current loop. The sensor detects changes in the charging current through the insulation ground conductor, indicating the degradation of the dielectric properties between the foil layers. The sensor and associated electronic circuitry are enclosed in a housing adaptable to be used with a capacitance tap common to high voltage measurement and control apparatus.

Abstract: A calibration method for a potentiometer which provides indicia reflecting an accurate indication of actual electrical resistance throughout the resistive range of a particular potentiometer. The indicia includes a number of graduation marks or symbols having a range and spacing unique to the resistive characteristics of the particular potentiometer. The indicia is fixed with respect to a known location associated with the particular potentiometer. The range and spacing of the indicia graduations is derived from measured resistance values at predetermined locations along the resistive member of the particular potentiometer.

Abstract: Disclosed is a method for making a laminate having utility in an electrical inductive apparatus, which first comprises coating at least one side of a metal substrate with a solventless liquid resin system comprising an ultraviolet radiation curable acrylic or vinyl monomer and a heat reactive thermoset adhesive resin. The resin system on the coated metal substrate is then exposed to ultraviolet radiation to cure the ultraviolet radiation curable monomer. The resin system is now a tacky solid layer. The laminates so formed can be assembled into components for use in applications such as electric power transformers, ignition coils, generators, chokes, reactors, solenoids ballasts, motors and electronics, in which prior art laminates have been utilized. The assembled laminates are then exposed to sufficient heat to cure the heat reactive thermoset resin and adhere the laminate layers together.

Abstract: The present invention provides a fuse holder as part of an integrated switch base assembly for attachment to a fusible switch having one or more phases between the line and load side of a circuit. The fusible switch has a switch base assembly for opening and closing a switch contact. The switch base assembly has a mounting surface. The fuse holder includes a generally planar base made of electrically-insulating material. The base has a top and bottom face. The top face has a plurality of upstanding walls integrally formed therewith which define a compartment corresponding to each phase. The bottom face has a contoured surface adapted to abut the mounting surface of the switch base assembly. A first and second fuse clip correspond to each phase and are secured on opposite ends of the top face within the compartment. A terminal connects to the load side of the circuit and electrically and mechanically connects to the first fuse clip. The fuse holder includes an elongated connector having two ends.

Abstract: A control system (FIGS. 2, 3, 5, 6) and method in which multiple levels, or stages (128, 130, 132), of logical decisions are made by selectively feedforwarding output signals (356) from control modules (72) to the inputs of other modules (80), preferably through use of control modules (233) with selective feedforwarding circuits (239, 240) to logically combine during selected synchronous time slots (351) of a synchronous clock signal (FIG. 11) the result of a plurality of nonconcurrent input signals from a plurality of input devices (28, 30, 32, 34) to control an output device (26).

Abstract: A programmable data link module (32) for use in a time division multiplexing control system (30) having a plurality of modules interconnected by a bus (40) for passing control signals between data link modules on a serial multiplex basis. Each module includes an integrated circuit (80) having signal conditioning circuits (180, 186 and 188) including a programmable hysteresis circuit (126), a power on reset delay circuit (190), a safety input inhibit circuit (220), a clock loss detect circuit (240), a safety output protection circuit (262), a data verifier (260), a polarity selector for a third output terminal (350), an input synchronizer (182 and 184), a combined mode/sync output terminal (110), a multiplex clock output terminal (108), a programming circuit (232) for accepting programming over the clock bus (44) and data bus (46), input/output word extender circuits (104, 106), a high voltage protection circuit (420) including a transistor (600) and a data bus integrity checker (630).

Abstract: There is disclosed a two wire AC power supply for proximity switch integrated circuits. A problem has existed with previous power supplies in that such have been implemented using discrete devices, which take up valuable room on any printed wiring assembly. This invention therefore provides a two wire AC power supply for a proximity switch integrated circuit, wherein at least some circuitry associated with the power supply is provided within the integrated circuit. The power supply preferably comprises a bridge rectifier (BR1), a voltage regulator (Z1, R1, M1), a thyristor (SCR), a diode (D1), a storage capacitor (CVS), a comparator, and an AND gate, wherein at least the comparator and the AND gate are provided within the integrated circuit.

Abstract: A blade suspension assembly for a circuit breaker comprises a pivot pin, a torsion spring, an elongated blade, and a blade carrier. The torsion spring includes a lateral middle section, a pair of end legs disposed on opposite sides of the middle section, and a lateral hole extending therethrough. The blade includes an electrical contact mounted thereto, a lower bearing surface, and a lateral circular aperture. The blade carrier includes first and second pairs of bearing surfaces. To assemble the blade suspension assembly, the torsion spring is placed over the blade with the lateral middle section abutting the lower bearing surface of the blade, with the end legs disposed on opposite sides of the blade, and with the lateral hole in the torsion spring disposed in line with the circular aperture in the blade. Next, the pivot pin is inserted through the lateral hole in the torsion spring and through the circular aperture in the blade.

Abstract: A ground fault detection circuit monitors an interlock control circuit for use with a machine or process control system. The interlock control system utilizes electromechanical relays with hard contacts. The interlock control system will disable operation of the machine or process if any ground fault condition exists in the interlock control circuit. A ground condition in the machine or process control circuits is permissible. The system uses a redundant circuit path to verify the integrity of the components in the interlock control system. The control system includes an ungrounded isolation transformer for supplying power to separate monitoring relays interposed between each leg of the transformer and ground. The contacts of these relays are series connected with emergency-stop (e-stop) switches to energize interposing control relays. The outputs of the interposing relays are used to energize the final control relay that controls the operation of the machine or process.

Abstract: A power distribution switchboard assembly is provided which is adapted to accept plug-in outgoer mechanical base fixing/location arrangements or units having different physical size and format. The switchboard assembly includes at least two rear mounting plates each formed with interspersed different format apertures in a longitudinal direction. The two rear mounting plates are located in juxtaposed relationship and are adjustable in a lateral direction so as to be spaced apart by different specified distances and together be capable of accepting different sized plug-in outgoer arrangements.

Abstract: A neutral lug assembly for coupling neutral wire conductors to a neutral plate in the panelboard is provided, the neutral lug assembly includes a generally u-shaped bracket adapted to be electrically coupled to the panelboard neutral plate and having first and second stair-step shaped side portions. A cross strap having a first end secured to the first side portion, a second end secured to the second side portion and a middle portion. A securing means is provided for securing the first and second end of the cross strap to the first and second side portions of the bracket, wherein the securing means electrically couples the cross strap to the first and second side portions. A connector is coupled to the middle portion of the cross strap for coupling at least one neutral wire conductor to the bracket.

Abstract: A remotely controllable circuit breaker device for interrupting power in a circuit path between a source and a load includes local and remote monitoring capabilities and a worm-gear mechanism for reliable control of the interruption mechanism. The device includes a first contact and a second contact cooperatively arranged in the circuit path so as to provide current from the source to the load. At least one of the contacts are movable for interrupting the power provided to the load. The worm gear mechanism includes a motor with a rotatable shaft which responds to open and closed control signals generated from a remote location, and a gear, rotatably responsive to the rotatable shaft, for controlling the movable contact so that the circuit path is interrupted and established, respectively. The worm gear mechanism controls the movable contact using a coupling arrangement, which has a first part coupled to the movable contact and a second part coupled to the gear.

Abstract: The present invention defines a convertible electrical contact. The convertible contact comprises two pair of movable contacts attached to an actuator which is supported by and enclosed within a housing. The actuator is biased to a first position and is slidably movable to a second position in response to a force applied to the actuator. The movable contacts are attached to the distal ends of a flexible member which is supported at its approximate midpoint by the actuator. The movable contacts are also movable between a first position and a second position as the actuator is moved. A pair of contact cavities are defined by the housing such that the one contact cavity lies on each side of the actuator and the flexible member and movable contacts are contained within the cavities. The housing defines a first pair of access apertures associated with the first position of the movable contacts and a second pair of access apertures associated with the second position of the movable contacts.

Abstract: A manually actuatable integrated contact module connecting to an output access module by means of a common communications link. The integrated contact module has an electrical contact, a logic circuit, a communications circuit and a communications terminal mounted on a common printed circuit board. The printed circuit board provides communication between the electrical contact and the logic circuit, between the logic circuit and the communications circuit, and between the communications circuit and the communications terminal. The printed circuit board is enclosed within a protective housing. A contact operator is slidably mounted with respect to the printed circuit board such that it is partially enclosed within the housing and movable between a first position and a second position.

Abstract: A modular circuit interrupter is arranged for interrupting current in a three-phase circuit path providing current from a three-phase source to a three-phase motor. The interrupter includes a contactor unit arranged to interrupt the circuit path in response to a trip command; a current inducer circuit for providing a current signal having a magnitude corresponding to the current in the circuit path; a fault detection circuit responsive to the current signal, for detecting and communicating power faults in the circuit path; and start and stop motor modules. Respective housings are provided for each of the contactor unit, the fault detection circuit, the start motor module and the stop motor module. A data/power communication bus provides a data communication link between each of the contactor unit, the fault detection circuit, the start motor module and the stop motor module.