This application discloses an electrical control device detection circuit, a detection method, and an electric vehicle. The detection circuit includes a drive circuit configured to detect an electrical control device. The drive circuit includes a drive power module, a high-side switch unit, and a low-side switch unit. The detection circuit includes: a detection power module, a first switch module, a second switch module, a first detection module, a second detection module, and a control module. The control module is configured to obtain an electrical signal at a third end of the first detection module and/or an electrical signal at a second end of the second detection module; and determine, based on the electrical signal at the third end of the first detection module and/or the electrical signal at the second end of the second detection module, whether a fault occurs in the drive circuit of the electrical control device.

Implementations of ground fault circuit interrupter (GFCI) self-test circuits may include: a current transformer coupled to a controller, a silicon controlled rectifier (SCR) test loop coupled to the controller, a ground fault test loop coupled to the controller, and a solenoid coupled to the controller. The SCR test loop may be configured to conduct an SCR self-test during a first half wave portion of a phase and the ground fault test loop may be configured to conduct a ground fault self-test during a second half wave portion of a phase. An SCR may be configured to activate the solenoid to deny power to a load upon one of the SCR self-test or the ground fault self-test being identified as failing.

Testing device for testing an overcurrent protector, and method of operating the same. First and second switches are provided for connecting the first and second terminals of the overcurrent protector to first and second capacitors, respectively. The first and second capacitors are pre-charged to first and second voltages, where the second voltage is lower than the first. A controller switches the first and second switches to their test positions, which establishes a current path from the first capacitor to the second capacitor through the overcurrent protector. The first and second voltages are selected so that the peak current that would be generated in the current path is greater than the overcurrent threshold of the overcurrent protector.

A method for identifying a malfunctioning current sensor in an electrical apparatus, in which an electrical power supply of the electrical apparatus is at least partly supplied by a switched-mode electrical power supply circuit connected to at least one current sensor which samples an electrical current in a phase conductor of an electrical installation, the power supply circuit delivering a regulated electrical voltage, the method including: determining a switching duty cycle of a power switch of the switched-mode electrical power supply; analysing the determined switching duty cycle; and identifying a failure condition if the behaviour of the switching duty cycle is representative of a malfunctioning of at least one of the current sensors.

A circuit interrupting device including one or more line terminals for connecting to an external power supply, one or more load terminals for connecting to an external load, one or more contacts electrically connecting one or more line terminals to one or more load terminals, and an auto-monitoring circuit. The auto-monitoring circuit configured to monitor one or more signals to determine an operating state of said circuit interrupting device, output a first signal having a first voltage level based on the operating state, wherein the first voltage level is greater than zero volts, and output a second signal having a second voltage level based on the operating state, wherein the second voltage level is greater than the first voltage level.

An apparatus includes a safety fault interrupter circuit. The safety fault interrupter circuit includes a safety fault monitor coupled to a first bias node and configured to selectively assert a fault interrupter signal based at least in part on a first bias voltage and a first power consumption. The safety fault interrupter circuit also includes a power fault monitor for the safety fault monitor, wherein the power fault monitor is coupled to a second bias node and is configured to selectively assert the fault interrupter signal based at least in part on a second bias voltage and a second power consumption that is less than the first power consumption.

A circuit interrupting device including one or more line terminals for connecting to an external power supply, one or more load terminals for connecting to an external load, one or more contacts electrically connecting one or more line terminals to one or more load terminals; and an auto-monitoring circuit. The auto-monitoring circuit continuously monitoring one or more signals to determine an operating state of said circuit interrupting device. Wherein if said auto-monitoring circuit determines that said circuit interrupting device has reached its end-of-life and it is determined that the contacts have not failed, then a signal is driven to a first level to actuate a switch and open the contacts. Wherein said signal is further driven to a second level to inhibit said circuit interrupting device from resetting when it is determined that contacts of said interrupting device have failed. Wherein the second level has a voltage greater than zero volts.

A functional safety system with high reliability is provided. The functional safety system includes power source apparatuses VS1 and VS2, voltage monitoring apparatuses VM1 and VM2, semiconductor devices SC1 and SC2, interruption circuits IN1 and IN2, and a motor MT. A the voltage converting circuit DA1 of the voltage monitoring apparatus VM1 generates a detected voltage VA1 from a power source voltage VDD1 on the basis of a switching signal VC1, and a voltage converting circuit DA2 of the voltage monitoring apparatus VM1 generates a detected voltage VA2 from the power source voltage VDD1 on the basis of a switching signal VC1.

Safety power disconnection integrity check for power distribution over power conductors to radio communications circuits monitors the integrity of circuit breakers may be used in an operating protection circuit as well as the integrity of current sensors in the operating protection circuit. Such monitoring includes testing the ability of individual switches to disconnect, testing the correctness of a leakage current sensor reading, and testing a correctness of an over current sensor reading. To perform these tests, the individual element is isolated and provided a test current. Any alarms generated by the element under test are diverted so that operation continues normally. Testing the safety power elements ensures that faults in the systems are detected and corrected so as to improve overall safety. Further, manual testing, which may interrupt service, is avoided.

This application provides a noise generation circuit, a self-checking circuit, an AFCI, and a photovoltaic power generation system. The noise generation circuit includes a power switch module, a noise generator, and a capacitor, where the noise generator is connected to both the power switch module and the capacitor; the power switch module is configured to control, according to a self-checking instruction, whether the noise generator generates a noise signal; and the capacitor is configured to filter out a direct current component in the noise signal when the noise generator generates the noise signal. According to the noise generation circuit, the self-checking circuit, the AFCI, and the photovoltaic power generation system that are provided in this application, no noise signal is generated in a non self-checking time, thereby ensuring normal working of the AFCI and the photovoltaic inverter.