Abstract: A method for controlling a static converter connected to a direct-current source. The converter has power conductor switches that can be deactivated and is configured to supply a distribution network with three-phase voltage. The currents flowing through the respective power semiconductor switches are measured, current values respectively assigned to the power semiconductor switches are obtained, the current values are sampled and digitized to obtain digital current values. The latter are checked by a logic in a control unit for the presence of an excess current condition. If no excess current condition is detected, the power semiconductor switches are activated and deactivated with the aid of a nominal operation controller and if an excess current condition is detected, at least the power semiconductor switches with assigned digital current values that fulfill the excess current condition are deactivated after a pulse block has expired.

Abstract: A multiple function safety compliance test instrument includes a high voltage output switching relay protected by a solid state in-line circuit breaker.

Abstract: A user adjustment assembly for translating user-adjustable dial settings to tripping levels of an electronic trip unit includes a potentiometer and an adjustment button. The potentiometer is positioned inside a cover of the trip unit and includes a potentiometer button. The adjustment button is coupled to the potentiometer for mechanically adjusting it and includes an insulation disc for increasing resistance to electrostatic discharge, preventing contaminants from entering the printed wire assembly components, and preventing application of downward force to the potentiometer button. The insulation disc has a bottom surface that is dimensioned to be larger than the potentiometer button. The adjustment button includes one or more stops that trigger a fail safe operation mode where the tripping levels are automatically adjusted to higher or predetermined protective levels when the adjustment button is moved to those stop positions. Switch calibration is obviated and the simplified design reduces overall cost.

Abstract: An electronic filter for filtering the output signal of a current sensor of a circuit breaker is disclosed. The current sensor has an output signal characteristic similar to that of a Rogowski coil output signal characteristic that includes a third harmonic noise component in response to a switching primary current of the circuit breaker, and the circuit breaker has an electronic trip unit with an instantaneous pick-up setting responsive to the output signal of the current sensor. The electronic filter includes a first stage and a second stage. The first stage has a first transfer function that defines first characteristic poles and permits passage of the third harmonic noise component. The second stage has a second transfer function that defines second characteristic poles and filters the third harmonic noise component.

Abstract: A method and occupancy-based control device in a trip unit of a main circuit breaker, with the circuit breaker coupled to an electrical distribution system including at least one feeder circuit breaker and a load circuit. The occupancy-based control device comprises an input device associated with the electrical distribution system and coupled to the trip unit. A selector is coupled to the trip unit and configured to select a first set of parameters and a second set of parameters, with each set of parameters defining a mode of operation of the trip unit. A means for selecting one of the first set of parameters and a second set of parameters in response to a signal from the input device is provided wherein, the trip unit operates based on the selected set of parameters.

Abstract: A cellular telephone 1 measures a current value after being turned on, and performs addition and subtraction of a predetermined margin to and from the measured value, and thereby sets up determination thresholds for an overcurrent and an undercurrent, namely, a minimum current value and a maximum current value, respectively. Here, the predetermined margin includes minimum allowance required (B) as a standard, a variation (E) in voltage of a power source of the cellular telephone 1, and a variation (D) in an operating temperature of the cellular telephone 1.

Abstract: The present invention relates to intelligent fuse box (1) for a vehicle's multiplex power distribution system, the fuse box including outputs (3) for driving the vehicle's functional components/actuators and/or cable buses (11–13) equipped with intelligent_nodes (14), the latter in turn having outputs for driving functional components/actuators (15), and further including means serving fuse functions between the outputs (3; 11–13) and the vehicle's power supply bus (12). The fuse-function means are controlled solid-state switches (4). The fuse box (1) includes inputs (5) for receiving messages controlling the ON/OFF state of solid-state switches (4) and a microprocessor (6), the latter controlling the solid-state switches (4) based on a program stored in the microprocessor memory (7) and on current limits predetermined in configuration data (8).

Abstract: A digital protection and control (P & C) device for a power distribution network, which comprises a computerized control unit comprising a microprocessor. The P & C device, according to the present invention, further comprises an external computerized palmtop computerized device, including a human-machine interface (HMI), which comprises a software communication platform. This software communication platform is aimed at exchanging, by means of a predefined communication channel, data/information related to the software configuration of the HMI and data/information related to the operating status of the P & C device.

Abstract: An electrical power breaker includes an electronic protective device and an electronic memory. The memory is accommodated in the power breaker such that it is physically separated from said protective device, for operational data for the power breaker. Data security when using the additional electronic memory is increased by the electronic memory being connected to the protective device via a data bus, which can be used to transmit control signals for the purpose of activating or deactivating a write protection device of the electronic memory. The data bus is preferably an I2C bus, and the write protection device is controlled by an I/O module which is likewise controlled by the I2C bus.

Abstract: A detection circuit includes a first power line, a first signal conditioning module operationally coupled to the first power line, a neutral line (N) operationally coupled to the first signal conditioning module, a second signal conditioning module operationally coupled to the first power line, a second power line operationally coupled to the second signal conditioning module, and an analog to digital (A/D) converter operationally coupled to the first and the second signal conditioning modules.

Abstract: Embedded controller(s) in an information handling system have real-time status and activities represented by indicators, such as light emitting diodes (LEDs), associated with the embedded controller(s). These indicators may be monitored for example by operating (management software, e.g., Embedded Server Management (ESM) software. In addition, edge triggered latches and a timer detect and store flash patterns of these LED indicators so that the flash pattern information may be read by the operating management software as static signals.

Abstract: A universal vehicle electric power distribution module employs reconfigurable inputs and outputs enabling use of the same hardware across vehicle lines. The module is scalable for ease of expansion and is capable of handling both low current and high current load management on the same module.

Abstract: An electronic fuse comprising an integrated circuit having a control output terminal coupled to a control electrode of a power semiconductor switching device, the power semiconductor switching device being coupled in series with a load between first and second potentials, the integrated circuit further comprising a current sense input for sensing the current through the power semiconductor switching device, the integrated circuit further comprising a driver circuit for driving the power semi-conductor switching device, the driver circuit being coupled to a current limiting circuit responsive to the sensed current in the power semiconductor switching device, the current limiting circuit controlling the driver circuit whereby if the current through the power semiconductor switching device exceeds a predetermined threshold, the current limiting circuit generates a command to pulse the power semiconductor switching device on and off in a period of pulsed operation to maintain the current in the power semiconducto

Abstract: The protection circuit (30) comprises at least one switch (FET1, FET2) comprising at least one control means (G1, G2) for adjusting the conductivity of said at least one switch (FET1, FET2). The conductivity is arranged to be adjustable by means of an electrical control conducted to the control means (G1, G2).

Abstract: An algorithmic system for an electronic trip unit is provided whereby reliable instantaneous protection is provided. A multi-algorithmic approach uses an algorithm to detect bolted faults based on a direct comparison of the current and a threshold value, and an additional algorithm to detect current overloads based on a comparison of a peak-to-peak current and an additional current threshold.

Abstract: A power management switch arrangement can be programmed by an external switch controller to alter the operating parameter limits used for fault detection. The switch arrangement includes the capability for full diagnostic feedback of load current and over-temperature conditions.

Abstract: Disclosed are methods and apparatus for over-current detection in PWM power stages. Disclosed methods and apparatus provide over-current detection with adaptive filtering according to the pulse width of the PWM input signal. Methods and apparatus for their implementation are described for detecting the pulse width of a PWM signal in the PWM circuit. According to the detected pulse width, a digital delay less than the pulse width of the PWM signal is selected from among a plurality of available digital delays. Further, an over-current condition in the PWM power stage is detected. The detected over-current signal is filtered by means of the selected digital delay and an over-current detection result is output.

Abstract: A combined current and voltage sensor includes: a combined sensor shell; a current sensor located in the combined sensor shell, the current sensor disposed proximate to said first load strap; and a first voltage sensor located in the combined sensor shell, the first voltage sensor disposed proximate to the first load strap. A circuit breaker includes: a first load strap in electrical communication with an electronic trip unit; a breaker in electrical communication with the electronic trip unit; a current sensor disposed at the first load strap; and a first voltage sensor disposed proximate the current sensor.

Abstract: Improvements to a rating plug for an electronic trip unit of a circuit breaker are disclosed. The rating plug includes a non-volatile memory which has access to current and frame rating information. A microcomputer in the electronic trip unit may receive new current rating information over the World Wide Web from a vendor system to update the current rating information of the rating plug. A program within the circuit breaker may detect errors in the new current rating information and may reject such and revert to a safe mode of operation. A billing system may be connected to the vendor system for calculating charges based on the transmission of the new current rating information. Preferably, the non-volatile memory of the rating plug is programmed at the factory site and a label adhered to the outer case of the rating plug for indicating the current rating.

Abstract: A fault warning system controls light sources and a warning signal to provide an indication of fatal and non-fatal faults in a communication system. The circuitry uses a pull-down circuit in electrical communication with light and signal control circuits. The circuit can be operated to activate a first light emitting diode (LED) if an operational status of a monitored circuit is either fatal or non-fatal fault. The circuit can be operated to deactivate a second LED if an operational status of a monitored circuit is fatal, and the second LED remains active if the operational status of the circuit is a non-fatal fault.

Abstract: A method and apparatus for rejection of an inappropriate rating plug in an electronic trip unit for a circuit breaker including: a microprocessor programmed to determine an overcurrent condition of the circuit breaker; a nonvolatile memory in operable communication with the microprocessor; the rating plug releasably engaged with the microprocessor, the rating plug includes an identification register; wherein the microprocessor reads the identification register, the identification register includes an identification number; wherein the microprocessor accesses one of a plurality of programs in the nonvolatile memory based on the identification number; and wherein the one of a plurality of programs instructs said microprocessor to perform a validation of said rating plug for operation with said microprocessor.

Abstract: The invention relates to a protection circuit (30) which includes at least one switch (FET1, FET2) including at least one control means (G1, G2) for adjusting the conductivity of the at least one switch (FET1, FET2). The conductivity is arranged to be adjustable by means of an electrical control conducted to the control means (G1, G2).

Abstract: Motor stall can be detected without the use of additional sensors in a hybrid stepper motor through the detection of a harmonic component an associated motor spectrum. The associate motor spectrum can be a motor command voltage spectrum. For example, all of the harmonic components except for the second harmonic are eliminated from the voltage and the presence or lack thereof indicates whether or not the motor has stalled. The harmonic component can be isolated with the use of several cascaded filters. These filters can include notch filters and bandpass filters. Additionally, the circuit may be realized as either an analog, digital or hybrid circuit. The motor may be either hybrid stepper motor having 2, 3, or 5 phases, or a variable reluctance motor.

Abstract: A digital multifunction relay, for controlling one or more protection devices of an power distribution network from fault events, which comprises a digital signal processor for executing a set of processing activities for regulating the operating state of said protection devices. The digital signal processor comprises a first computerized means for calculating the run-time computational load related to said digital signal processor and a second computerized means for reducing said run-time computational load, if said run-time computational load exceeds a predefined threshold.

Abstract: An electrical distribution device having a main part including a main breaking device, at least one secondary part having at least one secondary breaking device, and an electrical power distribution line connected between the main and secondary parts. The secondary breaking device includes secondary control circuit for enabling opening of at least one secondary breaking device if a current flowing in said breaking device is lower than a preset opening current threshold. A distributed electrical installation includes at least one such device. An electrical protection process for an electrical distribution device includes an opening step of the secondary breaking devices when a current flowing in these devices is lower than a preset opening current threshold following detection of a fault.

Abstract: A device includes a governor for controlling the frequency of the generator of a private power generation equipment, function generating means having a function characteristic for detecting the frequency variation rate of the generator and outputting a large output to the value thereof, effective power adjusting means for outputting an output proportionate to the signal, and protective relays for sensing abnormality of the frequency variation rate of the generator, so that, by making the signal in which an output from the function generating means and an output from the effective power adjusting means are synthesized an instruction signal of the governor, and shifting the frequency variation rate of the generator to a level sensed by the protective relays by the function characteristic of the function generating means at the power outage on the alternating current power line side, to detect the power outage on the alternating current power line side.

Abstract: An add-on unit for coupling to a main electrical appliance with separable power contacts, including a housing having a front face and a rear face, and for mounting frontally against or into such main appliance, wherein the front face includes first connections having an input-output function for connection with communication conductors for communicating with a device for control and monitoring of such main appliance, and second connections having an output function for connection with communication conductors for communicating with command input terminals of such main appliance, wherein the first connections are pins located in a connector on the front of the housing, the first connections comprising signal input connections to command such main appliance and signal output connections for signalling a status of such main appliance.

Abstract: A method is provided for optimizing the power consumption of a trip unit. The method comprises sensing a first output from a power system, the first output including a first current and a current-sensing signal; supplying a power supply with only the first current, or with a second current alone or in combination with the first current; powering a microprocessor from the power supply; inputting a second output to the microprocessor indicative of whether the power supply is receiving the second current; operating the microprocessor at a first state when the second output indicates the power supply is not receiving the second current; and operating the microprocessor at a second state when the second output indicates the power supply is receiving the second current alone or in combination with the first current.

Abstract: A method and apparatus is provided for protecting voltage regulation circuits and battery cells (“cell”) when a cell is reverse-coupled to a charger. When a charger is reverse-coupled to the cell, parasitic devices in voltage regulation circuits become forward-biased. When the parasitic devices become forward-biased, the parasitic devices may carry a current that is sufficiently large to damage the voltage regulation circuits. A shunt regulator is used to detect the presence of a reverse-coupled charger (“reverse charger”) and to shunt current to a ground potential such that potentially damaging currents are prevented from flowing through the parasitic devices.

Abstract: In a load for testing an energy production device, such as a fuel cell, a technique is provided for sensing one or more operational parameters for each of a plurality field effect transistors. Analog and digital feedback are provided to adjust the control signal to the FETs to ensure that each remains within its individual safe operating area. The technique preferably takes all of the various operational parameters into account to determine if any individual FET is approaching the SOA boundary, and prevent that single FET from leaving the SOA while continuing to manage the operation of the entire load.

Abstract: Motor stall can be detected without the use of additional sensors in a hybrid stepper motor through the detection of a harmonic component an associated motor spectrum. The associate motor spectrum can be a motor command voltage spectrum. For example, all of the harmonic components except for the second harmonic are eliminated from the voltage and the presence or lack thereof indicates whether or not the motor has stalled. The harmonic component can be isolated with the use of several cascaded filters. These filters can include notch filters and bandpass filters. Additionally, the circuit may be realized as either an analog, digital or hybrid circuit. The motor may be either hybrid stepper motor having 2, 3, or 5 phases, or a variable reluctance motor.

Abstract: Compatibility with a current transformer having several kinds of rated current ratios is achieved by finding out a formula of relationship between errors arising in a transformer input circuit and detectable ranges set as setting values of the input circuits which can be optimally set. In connection with that, by dispensing with a gain control section, the number of components, the mounting area and the cost can be reduced. Arithmetic expressions representing the relationship among errors arising in the transformer input circuit, the instrumentation ranges of the input circuits, and detectable errors have been derived. Further by optimally setting the detectable ranges of the input circuits, which are the parameters of the arithmetic expressions, the configuration compatible with a current transformer having several kinds of rated current ratios is achieved.

Abstract: A network protector relay controls a circuit breaker connected between polyphase feeder and network busses. A circuit samples polyphase circuit breaker current and network voltage to generate digital polyphase current and voltage samples. A microcontroller generates positive sequence current and voltage vectors from the current and voltage samples. A first trip algorithm trips the breaker in response to the positive sequence current vector being in a first trip region of a first trip characteristic with respect to the positive sequence voltage vector. The first trip characteristic is defined by a reverse trip setpoint and a first positive angle. A second trip algorithm trips the breaker in response to the positive sequence current vector being in a second trip region of a second trip characteristic with respect to the positive sequence voltage vector. The second trip characteristic is defined by the reverse trip setpoint and a second negative angle.

Abstract: A circuit breaker system 10 (FIG. 1) using electronic trip units 35 is disclosed. The electronic trip units 35 are coupled to a communications bus 30 whereby the electronic trip units 35 can be reconfigured, controlled, and/or monitored by a central computer. Further, the electronic trip units 30 include a data acquisition circuit 100 (FIG. 4) that uses chopping to provide better accuracy and increased dynamic range of current measurements.

Abstract: A power management switch arrangement can be programmed by an external switch controller to alter the operating parameter limits used for fault detection. The switch arrangement includes the capability for full diagnostic feedback of load current and over-temperature conditions.

Abstract: A method is provided for optimizing the power consumption of a trip unit. The method comprises sensing a first output from a power system, the first output including a first current and a current-sensing signal; supplying a power supply with only the first current, or with a second current alone or in combination with the first current; powering a microprocessor from the power supply; inputting a second output to the microprocessor indicative of whether the power supply is receiving the second current; operating the microprocessor at a first state when the second output indicates the power supply is not receiving the second current; and operating the microprocessor at a second state when the second output indicates the power supply is receiving the second current alone or in combination with the first current.

Abstract: A power lock device for safe power output/input is a control lock composed of coding devices, decoding devices and electromagnetic switches. The coded signal will attach to the power transmitting line and keeps on transmitting. After discerning that the coded signal is correct, the decoding device turns on electromagnetic switches and conducts power to transmit. If the code is not correct, the decoding device uses the electromagnetic switches to cut off power and achieves the function of power control.

Abstract: A method for predicting zero crossings of fault currents in a multi-phase power system includes sensing a fault current in each respective phase, estimating parameters of a model of each respective fault current, and independently using the estimated parameters for each respective fault current to predict a zero crossing of the respective fault current.

Abstract: Electrical equipment (14) is safeguarded from damage due to parallel arc faults by a circuit that provides several levels of protection. A semiconductor switch (18) and a current sensor (24) are placed in series with the electrical equipment (14). When the current to the equipment exceeds a first threshold for a predefined period of time, the semiconductor switch (18) is rendered non-conductive until the circuit is specifically reset. When the current to the equipment exceeds a greater second threshold, a pulsed signal alternately places the semiconductor switch (18) in conductive and non-conductive states so that the average current applied to the equipment (14) is within an acceptable level. The pulses are measured to determine whether a parallel arc fault has occurred. When the measured pulses (74) are within a predetermined range, a parallel arc fault is declared and the semiconductor switch (18) is rendered non-conductive.

Abstract: The thermal protection relay determines a value representative of the thermal image of an apparatus to be protected according to a measured current value, to a previous value of the thermal image and to preset heating and cooling time constants. The relay takes into account a non-zero initial thermal image, determined from experimental thermal resistance curves of the apparatus. In the case of a motor, for example, this enables the cold tripping curve of the relay to be lowered without modifying the hot tripping curve, so as to bring the tripping curves of the relay closer to the thermal resistance curves of the motor.

Abstract: A method and apparatus for rejection of an inappropriate rating plug in an electronic trip unit for a circuit breaker including: a microprocessor programmed to determine an overcurrent condition of the circuit breaker; a nonvolatile memory in operable communication with the microprocessor; the rating plug releasably engaged with the microprocessor, the rating plug includes an identification register; wherein the microprocessor reads the identification register, the identification register includes an identification number; wherein the microprocessor accesses one of a plurality of programs in the nonvolatile memory based on the identification number; and wherein the one of a plurality of programs instructs said microprocessor to perform a validation of said rating plug for operation with said microprocessor.

Abstract: A circuit breaker (10) (FIG. 1) has a power line (12) for carrying a power signal from a source to a load and a current transformer (14, 16, 18, 20) configured to sense the power signal and provide a sense signal based on the power signal at a first terminal (14a, 16a, 18a, 20a) (FIG. 2). The circuit breaker (10) includes a control circuit (26) configured to receive a first data message and to provide a second data message based on the first data message at a second terminal (40). The circuit breaker (10) further includes a programmable amplifier (30) coupled to the first terminal (14a, 16a, 18a, 20a) and the second terminal (40) configured to receive the sense signal, to receive the second data message, to amplify the sense signal based on the second data message, and to provide the amplified sense signal at a third terminal (42). A method of constructing the circuit breaker (10) is provided (FIG.

Abstract: A circuit breaker which displays electronically state of the circuit breaker and the cause of the disconnection which enables users to determine whether to reconnect a conductor which connects a source and a load in power distribution system. An arc display part is coupled to an arc fault detector, a ground display part is coupled to a ground fault detector and an overload display part is coupled to an overload detector. If arc fault occurs, the arc fault detector generates a trip signal and the trip signal is provided to the arc display part. As the trip signal from the arc fault detector is not provided to the ground display part and the overload display part, users can determine that arc fault has occurred by the lighting of the arc display part.

Abstract: An algorithmic system for an electronic trip unit is provided whereby reliable instantaneous protection is provided. A multi-algorithmic approach uses an algorithm to detect bolted faults based on a direct comparison of the current and a threshold value, and an additional algorithm to detect current overloads based on a comparison of a peak-to-peak current and an additional current threshold.

Abstract: A network protector relay controls a circuit breaker connected between polyphase feeder and network busses. A circuit samples polyphase circuit breaker current and network voltage to generate digital polyphase current and voltage samples. A microcontroller generates positive sequence current and voltage vectors from the current and voltage samples. A first trip algorithm trips the breaker in response to the positive sequence current vector being in a first trip region of a first trip characteristic with respect to the positive sequence voltage vector. The first trip characteristic is defined by a reverse trip setpoint and a first positive angle. A second trip algorithm trips the breaker in response to the positive sequence current vector being in a second trip region of a second trip characteristic with respect to the positive sequence voltage vector. The second trip characteristic is defined by the reverse trip setpoint and a second negative angle.

Abstract: A method and apparatus for automated testing of a plurality of electrostatic discharge (ESD) devices on a wafer. The wafer has M padsets and N conductive pads on each padset, where m is at least 1, and n is at least 2, and each ESD device is conductively coupled to a unique plurality of pads of a padset of the M padsets. Testing sequences, under program control of a computer system, implement the testing of the ESD devices.

Abstract: A contactor includes a switching circuit for switching a load between one or more electrical supplies, a current detector for detecting the current flowing through the load, a trip circuit for tripping the current after an interval of time which depends upon how much the current flowing through the load exceeds a predetermined amount, and a pre-trip circuit for providing an indication during said time interval that the current exceeds said predetermined amount for providing ‘pre-trip’ or ‘near-trip’ information.

Abstract: A circuit breaker system (100) providing application specific module (ASM) instantaneous overcurrent indication is disclosed herein (FIG. 5). A trip unit (110) included in the circuit breaker system (100) is powered by an external power supply unit (134) in the ASM (104). The circuit breaker system (100) includes transmitting an indication signal (130) from the trip unit (110) to the ASM (104) in response to an overcurrent condition. The indication signal (130) triggers a first controller (130) included in the ASM (104), the first controller (130) configured to cause the external power supply unit (134) to maintain power to the trip unit (110) for a first length for time sufficient to communicate a data corresponding to the overcurrent condition to the ASM (104).

Abstract: A system for supplementing existing safety devices in light circuits by real-time monitoring of current and voltage levels in light circuits to diagnose and pinpoint problems in the circuit, and to activate a safety disconnect in the event hazardous conditions are detected. The system includes a monitor device electrically coupled to a light circuit service panel. The monitor device includes a switching means complementary to an existing disconnect means operable to independently disconnect a light circuit from a power source, and input means for collecting real-time data from a plurality of circuits. The input means includes a means for detecting unequal current levels in the light circuits, a means for continuous surveillance of ground wire continuity for each light circuit, and means for continuous sensing of the current and voltage levels in each light circuit.

Abstract: A circuit breaker includes a pair of separable contacts forming a pole, an operating mechanism for operating the electrical contacts, an electronic trip circuit responsive to currents flowing through the pole for operating the operating mechanism in response to predetermined current conditions to open the separable contacts, and a fail-safe mechanism for operating the operating mechanism in response to a failure in the electronic trip circuit. The fail-safe mechanism includes a solenoid that is electrically connected to be energized in response to a failure in the electronic trip circuit and a linkage that operates the operating mechanism in response to operation of the solenoid. An operating arm that moves in response to the solenoid, interacts with operating mechanism to prevent resetting of the operating mechanism following actuation of the solenoid.