Abstract: An assembly and method is provided for a tripping mechanism of an circuit breaker to limit the damage to a protected circuit breaker and other associated equipment such as enclosures, bus way, etc. from the high forces that result from high currents and prevent unwanted tripping of a circuit breaker due to rapidly decreasing currents. A trip system for a circuit breaker including a sensor to determine a rate of change in the current level. A positive detector is connected to the sensor to determine a positive current direction. A negative detector is connected to the sensor to determine a negative current direction. An electronic switch connected to the positive and negative sensors to activate the tripping mechanism of the circuit breaker. A power supply is connected to the tripping mechanism and electronic switch.

Abstract: A core for a three-phase transformer, the core comprising a centrally-disposed flux collector and three generally C-shaped core leg sections peripherally arranged about the flux collector in an angularly spaced relationship and connected to the flux collector. The three core leg sections are each adapted to support a transformer coil and the flux collector is adapted to provide a low reluctance path to magnetically link the coils of the transformer.

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 one-piece self-aligning withdrawable finger cluster includes a plurality of members formed to surround a mating stab for making a removable electrical connection. The throat of the finger cluster is smaller than the mating stab, and, when mated with the stab, opposing members are biased against the stab.

Abstract: A circuit monitor monitors one or more metered values in an electrical circuit, and includes a system for selecting alarm setpoints based upon learned characteristics of normal operation of metered values. The circuit monitor includes a controller and a memory. The memory includes a test register of alarms selected to be part of a learning process. The controller includes summaries and characterizes the one or more metered values as histogram formatted data corresponding to metered values identified by a test register of alarms selected to be part of a learning process. The controller stores the histogram formatted data in the memory and organizes the stored data into a plurality of memory locations, each covering a fixed range of time duration. The controller selects setpoints which produce a minimum product of metered value multiplied by time duration for Over Alarms or a maximum product of metered value multiplied by time duration for Under Alarms.

Abstract: A circuit breaker comprises a line terminal, a middle terminal, and a load terminal, at least one of which is constructed from a positive temperature coefficient material and configured for introducing a predetermined resistance into the current path of the circuit breaker. The predetermined resistance is intended to limit current reaching a bi-metallic trip element as temperature rises so as to protect the bi-metallic trip element from excessive thermal stress, where the predetermined resistance increases with the increased temperature.

Abstract: A method and apparatus for detecting a partial discharge in a voltage transformer, the transformer having a first voltage winding and a second voltage winding. A grounded electrostatic shield being operably attached to the transformer, preferably between the windings. A radio frequency current transformer is operably connected to the electrostatic shield wherein the partial discharge occurring within the voltage transformer is detected.

Abstract: A circuit breaker for interrupting the flow of current upon the detection of excess current or temperature is provided that has a current conducting blade mounted on a blade cross bar, which has a blade biasing spring for urging the blade to a first pivotal position on the blade cross bar during the open, closed, and tripped operation of the breaker, and for latching the blade in a second pivotal position on the blade cross bar upon the occurrence of a blown-open action of the breaker. The spring is a torsion spring that is coiled around a spring mounting pin, having a first end leg extending outwardly and formed into a hook anchored in a hook accommodating opening, and having a second end leg extending outwardly and cantilevered in contact with a spring follower pin. The second end of this leg is bent away from the spring follower pin to reduce the spring force exerted between the blade cross bar and the blade upon the occurrence of a blow-open action of the circuit breaker.

Abstract: A circuit breaker for interrupting the flow of current upon the detection of excess current or temperature is provided that contains an arc plate assembly which includes a pair of insulative mounting plates having mounted thereon a set of arc plates arranged in an arcuate array generally tracing the arcuate path of movement of a circuit breaker moveable contact blade. A baffle plate is mounted between the insulative mounting plates and positioned above the uppermost arc plate in the set of arc plates for blocking arc-formed debris from projection into the operating mechanism of said circuit breaker. Mounting tabs, which are extending toward the insulative mounting plates from edges of the arc plates, are being used to connect the mounting plates with the arc plates by passing the tabs through corresponding apertures located in the mounting plates. The tabs are crimped against the exterior surface of the mounting plates.

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: An arcing fault protection assembly in an electrical outlet, and a corresponding method determine whether arcing is present in an electrical device connected to the outlet. The assembly comprises a sensor, a broadband noise circuit, a controller and s an electrical device. The sensor detects a current 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. The sensor, the broadband noise circuit and the controller are mounted to the outlet receptacle or to an outlet box which houses the receptacle. The electrical device is connected in parallel to the first electrical outlet on the load side of the sensor.

Abstract: A system clock for a system for measuring at least one given quantity having a value which does not vary significantly from a given frequency, the system clock comprises a controller for sampling said given quantity at a rate determined by an oscillator frequency, and a programmable oscillator for generating the oscillator frequency, said programmable oscillator being programmable to produce said oscillator frequency at a frequency which is substantially identical to a high order harmonic of said given frequency of the quantity to be measured.

Abstract: A field replaceable wiring adapter for interfacing a remotely operable switching device to a control device. The wiring adapter contains a set of terminals coupled to control wires extending from the switching device, a conversion circuit, and a second set of terminals coupled to the control device. The conversion circuitry converts a bi-directional current flowing from the control device in a single current path into two separate current paths that share a common conductor. The conversion circuitry extends between the first and second sets of terminals. The mounting element is used to mount the adapter to the control device. Since the wiring adapter contains the interface circuitry and necessary terminals, it may be easily installed or replaced in the field, for upgrade or maintenance purposes, with minimal disruption to power distribution services.

Abstract: An online monitor that can be permanently attached to a device to be monitored continuously monitors a set of analog signals and initiates data capture over a window of time when a user programmable set of conditions is satisfied. The online monitor includes a digital signal processing unit, a modular, interchangeable, analog signal conditioning base unit that can be tailored to the specific requirements of the process to be monitored and a modular, interchangeable, communication interface unit. The interface unit permits the digital signal processing unit to exchange data with external equipment such as network computers via a number of industry standard communication fieldbus protocols. The online monitor provides the capability to define the trigger condition under which data capture is initiated by comparing a user defined signal to a function of the instantaneous value of another signal or constant.

Abstract: A method and device for immunizing a contactor circuit from the inductive effects of a holding coil derived power supply, including: sensing a voltage signal from a power supply, the voltage signal having a switching range comprising an upper voltage and a lower voltage; providing a drive output responsive to the upper voltage; holding the drive output at a constant level as the voltage signal remains above the lower voltage; and, disabling the drive output in response to the voltage signal droppings below the lower voltage.

Abstract: An economical digital voltage sag compensator for overcoming sags in distributed electrical power. The voltage sag compensator employs an inexpensive micro-controller, a full wave bridge rectifier, a DC power supply, a voltage divider and an output switch. The micro-controller continuously monitors and evaluates, with respect to a setpoint measured in volt-seconds, the rectified DC voltage. At regularly spaced trigger events, as determined by the micro-controller, the micro-controller concurrently monitors the rectified DC voltage, evaluates the monitored voltage with respect to the setpoint, produces an output signal and sends that output signal to the output switch. The output switch supplies an electrical device, connected electrically in series with the full wave bridge rectifier and the output switch, with a constant average current of sufficient level to maintain the electrical device in a desired operating condition.

Abstract: The present invention provides 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. The invention also includes several methods for making electrical connections to the circuit breakers.

Abstract: A wide input range switching power supply for a circuit protection device includes a rectifier circuit for rectifying an AC line voltage at a supply input, and a switch-mode DC-to-DC converter coupled to the rectifier circuit for providing a low voltage DC power to a load at a supply output. The converter includes a switch having an open state and a closed state and a control circuit for controlling the state of the switch. The control circuit is operatively coupled to receive operating power from the supply output.

Abstract: An electronic trip device including an analog measuring for measuring electrical signals, analog-to-digital conversion having an input connected to the analog measuring an output having a first output signal, a digital processing means connected to the conversion for performing protection functions, and an offset correction. The offset corrections means are connected to the output of the conversion, and include high-pass digital filtering for computing an output signal value for each sample signal supplied by the conversion, according to an equation.

Abstract: A fuse base assembly for electrical fuses, including an electrical bus on which a load end fuse clip of the end-user's choice can be attached. The electrical bus is provided with means for attaching the selected load end fuse clip in a linearly adjustable manner such that the end user can adjust the spacing between the line and load end fuse clips as required for the desired fuse. The electrical bus is also provided with a load terminal attaching point such that wiring between the load device and the fuse is easily accomplished.

Abstract: A wide input range power supply for a circuit protection and/or fault detector device includes a passive supply for providing power to a load under nominal input voltage conditions at or near the nominal line voltage with minimum power loss, and a linear regulating supply path for assisting the passive supply at an input line voltage substantially below the nominal line voltage value.