A method for testing a device for monitoring an item of equipment of a motor vehicle. The method includes controlling a driver with a microcontroller in order that the driver performs at least one diagnosis, detecting an electrical fault of the monitoring device, positioning a switch connecting the driver and the circuit board in its open position, controlling the driver with the microcontroller in order that the driver reiterates the at least one diagnosis, and, in the event of the electrical fault being detected again, locating the electrical fault on the driver or, in the event of absence of detection of the electrical fault, locating the electrical fault outside the driver and in particular on the circuit board or between the driver and the circuit board.

A system and method for fault location and isolation in an electrical power distribution network, where the network includes a plurality of switching devices provided along a feeder. The method includes detecting an overcurrent event in the network from the fault and interrupting the overcurrent event by opening and then immediately locking out or subsequently reclosing and testing the fault. A count value is increased in each switching device that detected the overcurrent event. A count and current (C&I) message is sent from each of the switching devices that detected the overcurrent event and then detected the loss of voltage upstream to an upstream neighbor switching device. Current measurements in the C&I messages, measured current by the devices and the counts values in the devices determine what devices are opened to isolate the fault.

A method for fault location and isolation in a power distribution network, where the network includes a plurality of switching devices provided along a feeder, and at least one of the switching devices does not have voltage sensing capabilities. The method includes detecting an overcurrent event in the network from the fault and interrupting the overcurrent event by opening and then immediately locking out or subsequently reclosing and testing the fault. A count value is increased in each switching device that detected the overcurrent event. A message is sent from each of the switching devices that detected the overcurrent event and then detected the loss of voltage upstream to an upstream neighbor switching device. Current measurements in the messages, measured current by the devices and the counts values in the devices determine what devices are opened to isolate the fault.

The present invention corresponds to a method and an apparatus for detecting faults in transmission and distribution systems. The method is characterized by the steps of: a) Rectifying the ac current signal of the “auxiliary services” triphasic system; b) Rectifying and inverting the ac current signal of the transmission and distribution system; c) Connecting the step b signal to step a signal; d) Measuring the ac current signal obtained in step b; e) Measuring the dc current signal rectified in step a; f) Scaling the value of the current measured in step e by a scale k factor; g) Calculating the rms value of the signal measured in step d; h) Finding the difference between the values obtained in steps f and g; i) Comparing the absolute value of the step h difference with a reference value m; j) If the comparison made in step i is greater than the reference value m, a trigger signal is generated and the tension is maintained between the dc points of step b in about from 0 to 90%, of the operating tension with no fault. The apparatus comprises, a rectifier; an inverter connected to the rectifier; current measuring means at the rectifier and inverter outlets; and a control unit connected with the rectifier, the inverter and the current measuring means that makes the tripping command of the rectifier and the inverter, and compares the dc current measure at the rectifier outlet with the inverter outlet current, sending a tripping signal according to said comparison.

A method is disclosed for locating an earth fault in a DC network, to which multiple load zones are connectable. Each load zone has two symmetrically earthed load zone lines. In an embodiment of the method, for each load zone line, a line voltage is continuously measured between a line potential, at which the load zone line lies, and an earth potential. In the event that an earth fault is detected at a main line of the DC network, the main lines are separated from both load zone lines of a load zone and the earth fault is assigned to this load zone, if a magnitude difference between the magnitudes of the line voltages of the two load zone lines of this load zone are not significantly reduced after separating the main lines from the load zone lines.

A fault symptom sensing system comprises a slave station including an inference device to infer whether a fault symptom occurs in a power distribution line by inputting waveform data of an electric amount measured in the power distribution line or one or more feature values the waveform data to a trained model received from a master station. The slave station transmits the measured waveform data to the master station w hen the inference device infers that the fault symptom occurs. When the fault symptom actually occurs, the master station's learning device adds the waveform data received from the slave station or ore or more feature values of the waveform data to training data for updating the trained model, and performs additional learning to update the trained model.

The method for determining mutual voltage sensitivity coefficients between a plurality of measuring nodes of an electric power network does not rely on knowledge of the network parameters (for example: series conductance and susceptance of the branches, shunt conductance and susceptance of the nodes, etc.). The method uses a monitoring infrastructure including metering units at each one of the measuring nodes, and includes a step of measuring at the same time, at each one of the measuring nodes, repeatedly over a time window, sets of data including values of the current, the voltage, and the phase difference, a step of computing active power, reactive power and values from each set of measured data, and a step of performing multiple parametric regression analysis of the variations of the voltage at each one of the measuring nodes.

Testing to detect intermittent electrical pathways is described. Applied currents may be reversed to fully test all components of a workpiece. Various testing methodologies may be employed. These methodologies may include Time Domain Reflectometry (TDR), mechanical agitation, dark current/voltage testing, (dark IV), i.e., electrical testing of a workpiece using applied electricity, and thermographic imaging, e.g., infra-red thermal imaging. The sensed voltage during agitation may be compared to a benchmark voltage to determine whether or not an intermittent failure exists.

Described herein are methods and systems for detecting electrical discharges that precede electrical fires in electrical wiring. One or more sensor devices coupled to a circuit detect one or more signal waveforms generated by electrical activity on the circuit. The sensor devices identify one or more transient signals within the one or more signal waveforms, and generate one or more transient characteristics based upon the identified transient signals. A server communicably coupled to the sensor devices receives the one or more transient characteristics. The server analyzes the one or more transient characteristics to identify one or more electrical discharge indications. The server generates one or more alert signals when one or more electrical discharge indications are identified.

An electric utility distribution system in which power is supplied by a distribution transformer through an electric utility meter including an apparatus for detecting the presence of a back-feed voltage source connected to the load. The apparatus includes a virtual neutral established in the electric utility meter at ground potential and a remote switch that is opened to interrupt electric power flow from the distribution transformer to the load. The apparatus further includes a balanced voltage divider circuit including a connection point established between a pair of series connected resistive elements. In addition, the apparatus includes a detection circuit configured to monitor a voltage signal at the connection point to detect a back-feed voltage source connected between a neutral conductor of the electric utility distribution system and one of a first or second power line at the load.