A crowbar device has a first terminal and a second terminal, the terminals being connectible to a medium to high impedance AC voltage source including a trigger circuit configured to output a trigger signal responsive to exceeding a threshold voltage across at least one trigger element of the trigger circuit; a positive-side signaling circuit and a negative-side signaling circuit configured to output a positive or a negative clamping signal, respectively, according to a positive-voltage or a negative-voltage signal, respectively, input from the trigger circuit; and a positive-side overvoltage clamping circuit and a negative-side overvoltage clamping circuit configured to control their respective semiconductor element to be in a conducting state, when the clamping signal from the corresponding signaling circuit is present, and configured to control their semiconductor element to be in a non-conducting state, when the corresponding clamping signal has not been present for a predetermined time period.

The present invention provides for an electronic isolator device for application in intrinsically safe environments having isolation and safety functionality and comprising: an isolator module (101), a safety module (100), and wherein the isolator module is arranged for removable physical/electrical connection to the safety module in at least two orientations/configurations (DO, Dl, Al, AO) relative to the safety module, wherein the electrical connection to the safety module in each of the at least two orientations/configurations serves to configure the electrical functionality of the safety module (100).

Primary protection relays and an integrator disclosed for providing primary protection and secondary applications for an electric power delivery system. The primary protection relays obtain signals from, and provide primary protection operations for the power system, and may operate independently from the integrator. An integrator receives signals and status communications from the primary protection relays to perform secondary applications for the electric power delivery system. The secondary applications may include backup protection, system protection, interconnected protection, and automation functions.

An electronic system for a surgical instrument is disclosed. The electronic system comprises a main power supply circuit configured to supply electrical power to a primary circuit. A supplementary power supply circuit configured to supply electrical power to a secondary circuit. A short circuit protection circuit coupled between the main power supply circuit and the supplementary power supply circuit. The supplementary power supply circuit is configured to isolate itself from the main power supply circuit when the supplementary power supply circuit detects a short circuit condition at the secondary circuit. The supplementary power supply circuit is configured to rejoin the main power supply circuit and supply power to the secondary circuit, when the short circuit condition is remedied.

A residual current device includes an insulating housing, an electromagnetic induction module, a leakage current detecting module and an electromagnetic shielding structure. The insulating housing includes a base and a lid. The electromagnetic induction module is disposed in the base. The electromagnetic induction module includes a core base and an iron core. The leakage current detecting module is disposed in the base. The leakage current detecting module includes a circuit board assembly, a detecting circuit disposed on the circuit board assembly and a lead frame electrically connected to the circuit board assembly. The electromagnetic shielding structure is disposed in the base and covers the leakage current detecting module. The effect of preventing electromagnetic interference is achieved.

Ground-fault circuit interrupter positioned between energy controlled supply circuit and load circuit which includes fault detection circuit that senses ground path current leakage to the load circuit, fault processing circuit that detects presence of fault and generates fault output signal when fault detected, and control circuit switch connected to fault processing signal output, wherein control circuit switch is opened by presence of fault output signal, thus isolating load circuit from supply circuit. Preferably fault processing circuit and control circuit are optically linked, such that when fault is detected, control circuit switch is opened by optical fault output signal, thus isolating load circuit from the supply circuit. Circuit interrupter may couple another circuit interrupter via power distribution control unit, optionally manageable remotely via automated control interface.

An electronic functional device such as an isolator arranged to offer configurable functionality for alteration of the function of the device. The device includes wireless reception means for receiving wireless configuration data for the selective configuration of the device, and can also include wireless transmission means for the wireless transmission of data identifying its configured state.

Various implementations are directed to a method for detecting, by a device, an increase in temperature at certain parts of an electrical system, and taking appropriate responsive action. The method may include measuring temperatures at certain locations within the system and estimating temperatures at other locations based on the measurements. Some embodiments include an integrated cable combining electrical conduction and heat-detection capabilities, or an integrated cable or connector combining electrical conduction with a thermal fuse.

A circuit breaker for an electric load includes first and second terminals; a number of first separable contacts each electrically connected between one of the first terminals and one of the second terminals; a first mechanism to open, close or trip open the first contacts; a number of second separable contacts each electrically connected in series with a corresponding one of the first contacts; a second mechanism to open or close the second contacts; a processor to cause the second mechanism to open or close the second contacts, annunciate through one of the second terminals a power circuit electrical parameter for the electric load, receive from a number of the second terminals a confirmation from or on behalf of the electric load to cause the second mechanism to close the second contacts, and determine a fault state operatively associated with current flowing through the second contacts.

An item of electrical equipment has a preprocessing device for digital measured values. The preprocessing device has an integrated circuit and an electronic memory chip that contains a configuration of a logic circuit. If a fault of the preprocessing device is identified, an operation of the preprocessing device is interrupted until the configuration of the logic circuit has been loaded from a configuration memory chip into the electronic memory chip. There is also described a method for rectifying device faults, such as by reloading a configuration of a logic circuit into an electronic memory chip of a preprocessing device.