Circuit interrupter positioned between supply circuit and load circuit includes fault detection circuit that senses wave forms 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.

A motor drive device includes: an inverter circuit; a drive circuit which receives voltage supplied from a control power source; a first cutoff circuit which cuts off voltage supply from the control power source to the drive circuit; a second cutoff circuit connected between the first cutoff circuit and the drive circuit; a voltage detection circuit which detects a detection voltage corresponding to the voltage supplied from the control power source and which is capable of changing the detection voltage; a comparison circuit which, upon determination that the detection voltage is not within a predetermined range, cuts off the first cutoff circuit; and a diagnosis circuit which diagnoses the first cutoff circuit. The diagnosis circuit causes the comparison circuit to cut off the first cutoff circuit, diagnoses the first cutoff circuit, and upon diagnosing the operation of the first cutoff circuit as being abnormal, cuts off the second cutoff circuit.

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.

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 pantograph remote control circuit for an unmanned metro train includes a startup circuit of an auxiliary inverter emergency start relay, a control circuit of an auxiliary inverter energized relay, and a startup circuit of a pantograph raising relay. A first normally-open contact pair of the pantograph raising relay is serially connected to a pantograph raising electromagnetic valve and then connected to an output terminal of a battery. At the meantime, the bootstrap is remotely controlled by the internal ATC wake-up module when the power supply is fed by the battery, and there is no need for the driver to operate on the spot, thereby saving time for the driver from operations and reducing the potential misoperation of the driver.

A pantograph remote control circuit for an unmanned metro train includes a startup circuit of an auxiliary inverter emergency start relay, a control circuit of an auxiliary inverter energized relay, and a startup circuit of a pantograph raising relay. A first normally-open contact pair of the pantograph raising relay is serially connected to a pantograph raising electromagnetic valve and then connected to an output terminal of a battery. At the meantime, the bootstrap is remotely controlled by the internal ATC wake-up module when the power supply is fed by the battery, and there is no need for the driver to operate on the spot, thereby saving time for the driver from operations and reducing the potential misoperation of the driver.

A disclosed under-voltage lockout (UVLO) circuit includes an automatic UVLO threshold configuration. The UVLO circuit may include an over-voltage protection circuit that receives power from a power source, a peak detector that detects a peak voltage output for the power source, a voltage threshold generator that sets a UVLO threshold based on the peak voltage output, and a comparator that compares an instantaneous voltage with the UVLO threshold and configures an operating mode of a device based on the comparison.

A disclosed under-voltage lockout (UVLO) circuit includes an automatic UVLO threshold configuration. The UVLO circuit may include an over-voltage protection circuit that receives power from a power source, a peak detector that detects a peak voltage output for the power source, a voltage threshold generator that sets a UVLO threshold based on the peak voltage output, and a comparator that compares an instantaneous voltage with the UVLO threshold and configures an operating mode of a device based on the comparison.

A method for analyzing effects of electrical perturbations on equipment in an electrical system includes processing energy-related signals from at least one intelligent electronic device in the electrical system to identify an electrical perturbation in the electrical system. An end time of the electrical perturbation may be determined, and electrical measurement data from prior to, during and/or after the end time of the electrical perturbation may be analyzed to identify and quantify the effects of the electrical perturbation on equipment in the electrical system. The effects may include, for example, equipment restarts/re-energizations due to the electrical perturbation. One or more actions may be taken or performed to reduce the effects of the electrical perturbation and extend the life of the equipment. The actions may include, for example, at least one of communicating the equipment restarts/re-energizations and controlling at least one component in the electrical system.

A method for analyzing effects of electrical perturbations on equipment in an electrical system includes processing energy-related signals from at least one intelligent electronic device in the electrical system to identify an electrical perturbation in the electrical system. An end time of the electrical perturbation may be determined, and electrical measurement data from prior to, during and/or after the end time of the electrical perturbation may be analyzed to identify and quantify the effects of the electrical perturbation on equipment in the electrical system. The effects may include, for example, equipment restarts/re-energizations due to the electrical perturbation. One or more actions may be taken or performed to reduce the effects of the electrical perturbation and extend the life of the equipment. The actions may include, for example, at least one of communicating the equipment restarts/re-energizations and controlling at least one component in the electrical system.