Abstract: A ground fault protection system includes a power switch including a source-side and a load-side. The power switch is structured to receive a load current from a power source at the source-side and selectively output the load current from the load-side to a load. A first voltage measuring device is structured to measure a first voltage of the source-side while the power switch is not conducting the load current. A second voltage measuring device is structured to measure a second voltage of the load-side while the power switch is not conducting the load current. A controller is structured to determine a source-side-to-ground voltage based on the first voltage, determine a load-side-to-ground voltage based on the second voltage, determine a ground fault is occurring, and determine a direction of the ground fault relative to the power switch.

Abstract: Each grain bin includes a data collector coupled to multiple capacitive moisture cables, each with multiple sensor nodes spaced along it. Each sensor node includes a pair of longitudinally extending capacitive plates of the capacitive moisture sensor positioned in side-by-side, spaced-apart relationship to form a longitudinally extending gap between the capacitive plates. Positioned within the longitudinal gap between the capacitive plates is a circuit board including a microprocessor, memory, and temperature sensor. An outer housing provides a sealed enclosure that surrounds the circuit board, the capacitive plates, and a longitudinal length of the moisture cable that extends through and seals openings in each longitudinal end of the housing.

Abstract: In a process plant, a first series of measurements from a coupling interface are received. The first series of measurements are stored. A second series of measurements from a coupling interface are received. The second series of measurements. The first series and second series of measurements are compared. An indication of loss of clamping force is generated if the first series of measurements deviates from the second series of measurements.

Abstract: A PLC or other industrial controller programmed to locate ground faults in a networked high resistance grounded multi-drive system through network communications messaging to automatically place networked motor drives in various operational states to isolate individual drives for ground fault identification testing and selectively identify individual drives as suspected ground fault locations.

Abstract: A method for estimating the characteristic impedance of a structure comprising the following steps: providing a current probe comprising a magnetic core having an aperture therein and a primary winding wrapped around the core; measuring, with a calibrated vector network analyzer (VNA), the impedance (Zop) of the current probe while in an open configuration wherein nothing but air occupies the aperture and the current probe is isolated from a ground; measuring, with the VNA, the impedance (Zsh) of the current probe while in a short configuration, wherein the current probe is electrically shorted; measuring, with the VNA, the impedance (Zin) of the current probe while the current probe is mounted to the structure such that the structure extends through the aperture; and calculating an estimated characteristic impedance (Z?mast) of the structure according to the following equation: Z?mast=(Zin?Zsh)(Zop?Zsh)/(Zop?Zin).

Abstract: This invention relates to a method of detecting faults on an electrical power line (7) and a sensor (5) for use in such a method. Preferably, the sensor is a line-mounted sensor (5). The method comprises the initial step of determining an initial impedance profile for the power line (7), and thereafter the method comprises the subsequent steps of the line-mounted sensor (5) transmitting a conducted communication signal (41) along the power line, receiving a reflected signal (43) particular to the transmitted communication signal and correlating the transmitted signal and the reflected signal. By correlating the signals, it is possible to determine the actual impedance of the power line. The actual impedance of the power line may then be compared with the initial impedance profile and it is possible to ascertain whether a fault exists on the power line. Preferably, the method uses an adaptive filter to determine the location of the fault.

Abstract: A circuit for detecting fault conditions in a supply circuit includes a monitoring circuit and a comparator circuit. The monitoring circuit is operable to output a detection signal related to a control signal for the switched mode power supply. The control signal may be configured to operate at least one switch of the supply circuit between alternating activated and deactivated states to supply power to a load. The comparator circuit is operable to compare the detection signal to a range defined by first and second thresholds and output a fault signal according to a relationship of the detection signal to the range over a time period. Related methods of operation are also discussed.

Abstract: A method of monitoring an electrical power switching module of an underwater installation, the power switching module being operable to switch AC power in use is provided. The method includes the steps of measuring at least one operating parameter of the power switching module and producing a signal indicative of the measured parameter; if the signal is not digital, then converting the signal into a digital format; and outputting the digital signal on a bus. A power distribution unit for an underwater installation is also provided.

Abstract: An appliance and a method are intended to monitor a phase line of a section of an electrical energy grid line. The appliance comprises a device for monitoring a parameter of a phase line. The parameter is representative of routine operating conditions of the phase line and has a known propagation speed. The appliance also comprises a device for generating an event detection signal each time the parameter has a value that exceeds a threshold, and for storing a reception time when the detection signal is generated. The appliance also has a device for sending a signal representative of a geographic location of the end of the section and a device for performing a geographic location of the event once two consecutive detection signals are generated from the signal representative of the geographic location, and reception times associated with the two detection signals.

Abstract: An ambulatory infusion device for infusion of a liquid drug into a patient's body over an extended period of time and methods thereof are disclosed. The device includes a sensor assembly, which produces a sensor assembly output based on an infusion characteristic of the ambulatory infusion device and based on a supply voltage/current, and a supply unit which is coupled to a sensor of the sensor assembly and generates the supply voltage/current. A sensor testing unit detects a failure of the sensor assembly, wherein the sensor testing unit is coupled to the sensor assembly and the supply unit, and the sensor testing unit carries out a sensor testing sequence. The sensor testing sequence includes controlling the supply unit so as to produce a variation of the supply voltage/current, and determining whether the variation of the supply voltage/current produces a corresponding variation of the sensor assembly output.

Abstract: A compressor monitoring system includes current and voltage monitors, current and voltage averaging modules, a control module, and a switch. The current monitor measures a current drawn by a motor of a compressor. The current averaging module generates first and second average current values based on the current measured by the current monitor. The voltage monitor measures a utility power voltage. The voltage averaging module generates first and second average voltage values based on the voltage measured by the voltage monitor. The control module selectively generates a fault signal when a first ratio is greater than a first predetermined threshold and a second ratio is less than a second predetermined threshold. The first ratio is based on the first and second average current values. The second ratio is based on the first and second average voltage values. The switch deactivates the motor when the fault signal is generated.

Abstract: Methods are disclosed for identifying and locating points of impairment in a cable plant, such as that used for cable television (CATV). The methods utilize both known characteristics of signals as well as propagation times in free space and within the cable in conjunction with accurate determination of locations at which measurements are taken. The methods can be applied to both RF cable leaks as well as points of ingress of interference.

Abstract: There is described a method and a system for evaluating damage of a plurality of cells in an electrolyser. The method comprises acquiring a voltage for each one of the cells; comparing the voltage to at least two threshold voltage levels; classifying the cells as one of: severely damaged cells, non-severely damaged cells and undamaged cells, based on the comparison of the voltage with the at least two threshold voltage levels; and deactivating the cells classified as severely damaged cells from the electrolyser.

Abstract: Disclosed are embodiments of a system, method and service for detecting and analyzing systematic conditions occurring in manufactured devices. Each embodiment comprises generating a unique signature for each of multiple tested devices. The signatures are generated based on an initial set of signature definitions and the values for those signature definitions that are derived at least in part from selected testing data. A systematic condition is detected based on commonalities between the signatures. The systematic condition is then analyzed, alone or in conjunction with additional information, in order to develop a list of underlying similarities between the devices. The analysis results can be used to refine the systematic condition detection and analysis processes by revising the signature definitions set and/or by modifying data selection.

Abstract: Among the various embodiments described is a method of detecting defects in a cell of an integrated circuit that analyzes exercising conditions applied to an input of the cell during a capture phase of testing with failed test patterns that produce an indication of a fault and that analyzes the exercising conditions that are applied during a capture phase of testing with observable passing patterns that do not provide an indication of a fault. From the analysis, true failing excitation conditions and passing excitation conditions can be determined and used to identify whether a defect is in the cell or on an interconnect wire of the integrated circuit.

Abstract: A method and apparatus for cross-point detection in devices have been disclosed where each leg of a differential signal is compared to a reference voltage and time lags for each are noted in crossing the reference voltage and this information is used to identify characteristics of the differential signal.

Abstract: A system detects the wiring phase of an unknown phase voltage at a remote location relative to a reference phase voltage at a reference location in an electrical power distribution system having a single phase or poly phase power line. A transmitter transmits a signal from the reference location to the remote location. The signal comprises a characteristic signal pattern. Moreover, a first circuit detects at the remote location the characteristic signal pattern of the signal and determines a first time interval between the characteristic signal pattern and the occurrence of a reference point in the unknown phase voltage. A second circuit determines at the reference location a second time interval between the characteristic signal pattern and the occurrence of a reference point in the reference phase voltage. The system determines the wiring phase of the unknown phase voltage from the first time interval and the second time interval.

Abstract: In one embodiment, a plurality of signals are sequentially driven onto a signal path. Each of the signals has a pulsewidth defined by a trigger edge and a sensor edge, and at least some of the signals having different pulsewidths. After driving each signal, the signal is sampled at or about a timing of the signal's sensor edge to thereby characterize the signal's sensor edge. The sensor edge characterizations corresponding to the different signals are then analyzed to quantify a timing error induced by an impedance variation of the signal path.

Abstract: The present invention is a technique for locating and identifying a failed filter/arrester in an underground conveyance such as a fiber optic cable. A sensor is installed in the filter/arrester housing to sense grounding of a cable locating frequency. The sensor will monitor the cable locating signal that is normally on the cable and blocked by the filter arrester to ground. A small radio frequency oscillator (85 to 88 Hz), also installed inside the filter housing, is activated by the sensor. The RF signal is detected above ground with standard cable locating equipment. A warning indicator such as an indicator light may also be installed on the outside of the filter housing. The indicator is also activated by the sensor. In that way, the particular failed filter can be identified if multiple filters are installed at that location. The power that will be required to operate the RF transmitter and indicator will be obtained from the voltage passing through the cable.

Abstract: A method to locate a fault from one end of a section of a power line utilizing measurements of current, voltage and angles between the phases at a first end of said section. Symmetrical components of currents are calculated for the current and voltage measurement at the first end. A value of impedance is calculated for an extra link between the terminals with the impedance for the positive sequence. A compensation is determined for the shunt capacitance. The zero-sequence current is determined from the healthy line of a section of parallel power lines. A distance to a fault is calculated for the parallel line section. The distance to the fault from the first end is calculated. The fault is located utilizing the calculate distances.

Abstract: An apparatus and method is provided for sensing data relating to a structure (14), including an inspection site sensor system having at least one microprocessor (16) coupled to the structure. At least one sensor (12) for sensing data is connected to each of the at least one microprocessors that compare the data to a standard. A user interface (18) is coupled to the microprocessor (16) for presenting the comparison, and a wireless transmitter (20) is coupled to the microprocessor (16) for transmitting at least one of the data and the comparison to a management site (22). The management site (22) includes a receiver (24) for receiving the transmitted at least one of the data and the comparison, a microprocessor (26) coupled to the receiver (24); and a user interface (28) coupled to the microprocessor (26).

Abstract: A system and method for sensing the formation of tin whiskers is presented. An assembly substrate includes whisker detectors at various locations for detecting tin whiskers in an X direction, a Y direction, and a Z direction relative to the assembly substrate. Each whisker detector includes sense traces and a trace bridge that produce “planar gaps” and “orthogonal gaps” that are smaller than trace gaps produced by other traces on the assembly substrate. As such, tin whiskers short across the planar gaps and orthogonal gaps before they short across trace gaps. When the assembly substrate is finished with processing steps, a system tester performs a continuity test on the whisker detectors. When the continuity test fails, an operator is notified to check for tin whiskers on the assembly substrate. Once shipped, a processor monitors the whisker detectors for shorts throughout the product's lifecycle.

Abstract: A fault detection system includes a fault indicator and power monitors coupled to the fault indicator. The fault indicator is configured to indicate a fault for a first one of the power monitors which detects a corresponding voltage is not between a corresponding maximum value and a corresponding minimum value.

Abstract: A method and apparatus for diagnosing open defects on non-contacted nodes of an electrical device is presented. Actual and expected signal measurements are collected for various contacted nodes of the electrical device. Nodes whose actual measurements are out of range of their respective expected measurements are deemed abnormal nodes. Non-contacted nodes may then be assessed as having, or as likely to have, open defects based on knowledge of the degree of coupling of the non-contacted node to the abnormal contacted nodes. In the preferred embodiment, abnormal nodes are identified using a linear regression analysis, and the non-contacted nodes indicted as having open defects are identified using a weighting scheme.

Abstract: The present invention is a technique for locating and identifying a failed filter/arrester in an underground conveyance such as a fiber optic cable. A sensor is installed in the filter/arrester housing to sense grounding of a cable locating frequency. The sensor will monitor the cable locating signal that is normally on the cable and blocked by the filter arrester to ground. A small radio frequency oscillator (85 to 88 Hz), also installed inside the filter housing, is activated by the sensor. The RF signal is detected above ground with standard cable locating equipment. A warning indicator such as an indicator light may also be installed on the outside of the filter housing. The indicator is also activated by the sensor. In that way, the particular failed filter can be identified if multiple filters are installed at that location. The power that will be required to operate the RF transmitter and indicator will be obtained from the voltage passing through the cable.

Abstract: A method for evaluating the upper bound fault coverage of an integrated circuit (IC) or a portion thereof from register transfer level (RTL) description is provided. The method requires the analysis of a circuit described in RTL consisting of primary input and output pins as well as devices connected to each other and/or to the primary pins to determine the controllability and observability of each pin of the circuit to ‘stuck at zero’ and ‘stuck at one’ conditions. The upper bound fault coverage is then determined based on the ratio between the number of pins that are both controllable and observable and twice the number of pins in the circuit. The method does not require a dynamic simulation for its fault coverage assessment and hence is advantageous over other methods consuming significant time and resources.

Abstract: An anode monitoring system for monitoring the integrity of anodes 2 provided on a metallic structure such as a pipeline system 1. A signal circuit Sn including the pipeline 1 and one of the anodes 2 is set up and appropriate signals are looked for at a central station 4. Reception of the signal at the central station 4 is dependent on the integrity of the anode 2 under inspection at that time. If the anode 2 is missing or defective the expected signal is not received and thus the fault in the anode 2 can be detected. A notch filter 5 is inserted in series between each anode 2 and the pipeline 1. The filter 5 provides a high impedance which can be signalled across but does not interfere with the cathodic protection system.

Abstract: The present invention provides an improvement over conventional electric circuit monitoring devices in that it provides a device and method to passively monitor the performance of an electrical circuit to a load device, including faults that occur intermittently. The invention is capable of identifying the location and type of malfunction in the event of a fault.

Abstract: A sensor network has a plurality of resistors connected to row lines and column lines in a matrix. A monitoring resistor is connected between ends of two adjacent row lines. One of the row lines is connected to a pull-up resistor and the other row line is grounded to form a series circuit. When a voltage is applied to the series circuit, a voltage across the monitoring resistor is inputted to an ECU. If the circuit is in the shorted condition, the voltage across the monitoring resistor is 0. If the circuit is in the open condition, the voltage is equal to the voltage applied to the circuit. If no failure is present in the series circuit, the voltage is equal to the divided voltage. Failure detection in column lines is performed in the same manner as the row lines.

Abstract: An apparatus for monitoring a cellular communications system; comprising a plurality of voltage standing-wave ratio (VSWR) measurement means located at respective connections to antennas of said communications system and at respective discontinuities in radio transmission lines to said distributed antennas; wherein each said VSWR measurement means is individually identifiable, has a respective threshold, and is arranged to compare its measured VSWR value to its respective threshold and identifiably indicate an error status if its measured VSWR value exceeds its threshold. Also described is a corresponding method of monitoring a cellular communications system. Also described is a VSWR measurement apparatus, and an antenna arrangement comprising an antenna and such a VSWR measurement apparatus.

Abstract: An invention including an outer shell that can be used to provide separated conductors and a method for installing a conductor in the outer shell is disclosed. The invention can assume many different embodiments. The outer shell is adapted to retain a conductor and includes a base adapted to associate with a support surface. The outer shell also includes a hollow sensing portion that extends from the base and is adapted to retain a conductor. The sensing portion is spaced from the base a distance sufficient to accommodate a portable, hand-held current sensing device. The invention also includes a method of installing a conductor in the hollow sensing portion.

Abstract: The present invention relates to an apparatus and a method for detecting an open circuit fault condition in a differential signal, and generating a fault detection signal. An open circuit fault condition is detected by employing weak current sources to pull the differential signal paths outside the valid ac common-mode range and toward the supply rails. If both signal paths can be pulled within a predetermined proximity to the supply rails by their respective weak current sources, an open condition fault is defined to exist and a fault detection signal is generated. The fault detection signal can be used by another device to report the fault condition.

Abstract: An invention including separated conductors is disclosed. The invention can assume many different embodiments. The invention includes a chassis or body adapted to receive a first conductor and second conductor, the first conductor being separated from the chassis and the second conductor a distance sufficient to accommodate a portable, handheld current-sensing device. The first conductor has an insulating jacket and is generally less flexible than the flexibility of the first conductor without the insulating jacket. In addition, the invention preferably does not influence the current flow through the apparatus and the invention continues to provide electricity even if the current detector malfunctions.

Abstract: A method and apparatus for use with an electronic test system to enable the direct testing of buses on a unit under test (UUT). A connection and interface for an electronic test system are provided, which are simple to use, fast to connect and reliable, which may be used as an extra point of test and/or for testing buses remote from the microprocessor of a circuit under test, and which may also be used independently of any devices of the circuit under test. The test apparatus and method may be used to test buses remote from the microprocessor without the use of peripheral devices on the circuit under test, for example I/O chips.

Abstract: An apparatus for testing an electrical connection between a first electrical contact on a first side of an electronics package substrate and a first electrical terminal on a second, opposing side of the substrate. A holder is provided which is capable of releasably receiving and holding a substrate. At least a first electrical pin is located on the holder. The first electrical pin is positioned to contact the first electrical contact on the first side of the substrate. A support structure is mounted to the holder. An electrical probe is mounted to the support structure. The electrical probe is movable relatively to the support structure between a first position and a second position. In the first position the electrical probe is distant from the first electrical terminal on the second side of the substrate. In the second position the electrical probe is in contact with the first electrical terminal.

Abstract: A probe for fault-actuation devices has a transistor which is utilized to insert a reference signal into a fault-insertion point. The emitter and collector are connectable to the fault-insertion point and a reference signal and a capacitor with a capacitance greater than the capacitance of parasitic components is connected between the base and the emitter.

Abstract: A method of locating in a non-destructive and non-invasive manner power plane-to-power plane shorts or I/O net-to-power plane shorts found in a printed circuit board or a multi-chip-module by way of a magnetic field generating probe is described. Thousands of nets can be simultaneously tested to detect not only the presence of a short but also to accurately pinpoint its position. For high resistance shorts, the probe is provided with a pot core housed inductor located at its tip, and is used at low frequencies to minimize the effect of the capacitive impedance between the power planes. For low resistance shorts, the probe is used at high frequencies, delivering equal but opposite current to each of two matched inductors at the tip of the probe to maximize mutual inductive coupling while minimizing electrostatic capacitive coupling with the board or module. In both cases, the highest current stress is on the probe rather than on the expensive and fragile package under inspection.

Abstract: A semiconductor device manufacturing process diagnosis system including a visual inspection device for detecting a physically abnormal part of a semiconductor device to be diagnosed, an LSI tester for measuring electrical characteristics of a semiconductor device and a diagnosis device and characterized in that the diagnosis device extracts, from among circuit blocks constituting a semiconductor device, a block contained in a predetermined region covering a physically abnormal part, determines whether an extracted block and an abnormal block causing abnormality of electrical characteristics are the same, with respect to a block discriminated as an abnormal block, detects a position causing abnormality of electrical characteristics within the block, and depending on whether a detected position substantially coincides with a physically abnormal part, determines whether abnormality of electrical characteristics derives from physical abnormality.

Abstract: A method of measurement for fault distance determination on two or more parallel HVDC lines connected between two stations with a line fault locator is provided. The fault distance determination is performed by determining the difference in time, via synchronous clocks at each station, between travelling waves, which arise when a fault occurs, reach the two stations. The difference in time is determined by measuring the current associated with the travelling waves and detecting the current at the two stations and on each of the parallel connected lines.

Abstract: A fault locating system for locating a fault in an underground power distribution system includes a method and an apparatus. The underground power distribution system receives and distributes power from a bulk power source to power consumers through a fused switchgear unit and a first vault. The first vault distributes power from the fused switchgear unit among plural outgoing underground power lines, with each line supplying power to at least one power consumer. A current limiting apparatus for locating faults in the above system includes an enclosure of an insulative material defining a fuse receiving chamber. First and second bushings extend through the enclosure to the fuse receiving chamber. The apparatus has a current limiting fuse received by the respective first and second bushings within the fuse receiving chamber.

Abstract: A method and device for detecting defects in wire or cable insulation without disconnecting the cable by synchronously detecting the current in a sense conductor with respect to the potential waveform existing or imposed on the cable under test. Both the ion source and the sense conductor are placed in close proximity to the cable under test. The current flowing in the sense conductor due to the ions from the ion source varies depending upon the presence of defects in the cable insulation and the potential waveform present on the cable under test. The synchronous detection enhances the signal to noise ratio of the current measurement.