In order to provide an environmentally secured voltage testing interface, an electrical enclosure box comprising a front panel is herein-described, into which is mounted a voltage indicator comprising a plurality of LED indicators that indicate a status of one or more circuits coupled thereto and monitored thereby. A test point device is also mounted through the front panel and comprises an interface comprising a plurality of external measurement sockets configured to receive one or more probes for manual measurement of voltages, wherein each external measurement socket is coupled to a voltage divider that is further coupled to each of a plurality of respective wires coupled to respective LED indicators of the voltage indicator.

In order to provide an environmentally secured voltage testing interface, an electrical enclosure box comprising a front panel is herein-described, into which is mounted a voltage indicator comprising a plurality of LED indicators that indicate a status of one or more circuits coupled thereto and monitored thereby. A test point device is also mounted through the front panel and comprises an interface comprising a plurality of external measurement sockets configured to receive one or more probes for manual measurement of voltages, wherein each external measurement socket is coupled to a voltage divider that is further coupled to each of a plurality of respective wires coupled to respective LED indicators of the voltage indicator.

A leakage current detection device includes a self-test unit for activating a simulated leakage current signal; a leakage current detection unit for detecting the simulated leakage current signal and the actual leakage current signal, where when at least one of them is present, the leakage current detection unit activates a trigger signal, and when both of them are absent, the leakage current detection unit deactivates the trigger signal; a self-test feedback turnoff unit for detecting the trigger signal, where when the trigger signal is detected, the self-test feedback turnoff unit deactivates the simulated leakage current signal before a predetermined time point; and a power line disconnect unit for detecting the trigger signal after the predetermined time point, and when the trigger signal is detected, it disconnects the power between the power source and the load.

An electrical system can include a diagnostic device that generates a first test signal. The electrical system can also include multiple energy transfer links coupled to the diagnostic device, where the first test signals flows through a first subset of the energy transfer links. The electrical system can further include a first monitoring device coupled to the first subset of energy transfer links, where the first monitoring device receives the first test signal from the diagnostic device through the first subset of the energy transfer links. The electrical system can also include a first electrical device coupled to the first monitoring device. The first monitoring device can implement a first test procedure based on the first test signal, where the first test procedure helps determine a first condition of the first electrical device.

A method for line assignment of a short-circuit of a broadband lambda sensor having an upper or a lower short-circuit potential, wherein the broadband lambda sensor has a sensor and multiple sensor lines. The method comprises establishing a conductive connection of at least one sensor line of the multiple sensor lines via a limiting resistor to a reference potential; comparing a sensor line potential of at least one sensor line to be checked of the multiple sensor lines to the reference potential or the short-circuit potentials; classifying (105) the at least one sensor line to be checked as not short-circuited with the upper or the lower short-circuit potential if it is established upon the comparison that the at least one sensor line potential is inside the reference potential range or if it is outside the short-circuit potential ranges; and assigning the short-circuit to at least one sensor line not classified as not short-circuited.

A method for line assignment of a short-circuit of a broadband lambda sensor having an upper or a lower short-circuit potential, wherein the broadband lambda sensor has a sensor and multiple sensor lines. The method comprises establishing a conductive connection of at least one sensor line of the multiple sensor lines via a limiting resistor to a reference potential; comparing a sensor line potential of at least one sensor line to be checked of the multiple sensor lines to the reference potential or the short-circuit potentials; classifying (105) the at least one sensor line to be checked as not short-circuited with the upper or the lower short-circuit potential if it is established upon the comparison that the at least one sensor line potential is inside the reference potential range or if it is outside the short-circuit potential ranges; and assigning the short-circuit to at least one sensor line not classified as not short-circuited.

Provided is a load drive device capable of diagnosing a failure of an output terminal of the load drive device before a charging voltage stabilizes in a configuration in which a capacitor is connected to an output terminal of the load drive device that drives an inductive load. In the load drive device according to the present invention, a capacitor is connected between a load terminal and a ground terminal, and the presence or absence of a failure of the load terminal is diagnosed on the basis of a current flowing between an internal power supply included in a diagnosis circuit and the load terminal.

Provided is a load drive device capable of diagnosing a failure of an output terminal of the load drive device before a charging voltage stabilizes in a configuration in which a capacitor is connected to an output terminal of the load drive device that drives an inductive load. In the load drive device according to the present invention, a capacitor is connected between a load terminal and a ground terminal, and the presence or absence of a failure of the load terminal is diagnosed on the basis of a current flowing between an internal power supply included in a diagnosis circuit and the load terminal.

Disclosed herein are methods for determining resistance in an electric circuit, including the steps of: applying a voltage pulse to a test point of said electric circuit, said voltage pulse having a predetermined pulse duration; measuring an electric observable at a response point of said electric circuit during at least a part of said pulse duration; estimating during said pulse duration an expectation value from said measured observable; and determining said resistance from said expectation value. Also disclosed herein are devices for determining resistance in an electric circuit.

Disclosed herein are methods for determining resistance in an electric circuit, including the steps of: applying a voltage pulse to a test point of said electric circuit, said voltage pulse having a predetermined pulse duration; measuring an electric observable at a response point of said electric circuit during at least a part of said pulse duration; estimating during said pulse duration an expectation value from said measured observable; and determining said resistance from said expectation value. Also disclosed herein are devices for determining resistance in an electric circuit.