A method for monitoring a protective device, which has a series circuit of a multiplicity of thyristors. The protective device has a series circuit of N>1 thyristors. The series circuit is connected in a parallel circuit with an electrical device to be protected. A snubber branch is connected in parallel with each thyristor. For the purpose of testing a firing capacity, n<N thyristors in a first thyristor group are fired when a positive voltage is present across the series circuit and a negative snubber current is flowing through the snubber branches of the thyristors in the first thyristor group.

A surge protective device includes an overvoltage protection circuit and a control module coupled to the overvoltage protection circuit that is configured to monitor at least one performance characteristic of the overvoltage protection circuit and is further configured to communicate the at least one performance characteristic to a destination external to the surge protective device.

An over-voltage protection system is provided for use with electrical equipment. The system includes a protection circuit having a first bus for receiving electrical power, a second bus for providing power to the equipment and two parallel surge arresters connected between the first bus and ground. A main and backup bushing are arranged in parallel between the first and second bus. The main bushing is arranged in series with a normally closed contact maintaining the main bushing in service by default. The backup bushing is arranged in series with a normally open contact isolating the backup bushing by default. The protection circuit comprises a controller for testing the insulation of the arresters and bushings. The controller is configured to selectively actuate the contacts to selectively isolate, or incorporate, the arresters and bushings in the circuit to facilitate testing and maintenance while maintaining the protection circuit operational.

A protection circuit, and related method, for an electronic device including a first power output interface and a second power output interface is disclosed. The protection circuit includes a first switch element, coupled between a first voltage source and the first power output interface. The detection circuit being operation to detect an output voltage value of the second power output interface to generate a detection result. The first switch element, according to the detection result, connects the first voltage source to the first power output interface to allow the first power output interface to output power to an external terminal, or disconnects the first voltage source from the first power output interface.

A device, a method and a system for monitoring an electrical connection status of a disconnector device are disclosed. The disconnector device is connectable to pole-mounted equipment in a power distribution or transmission grid, thereby disconnecting the pole-mounted equipment. The connection status monitoring device includes a determining section configured to determine whether the disconnector device has been activated and to generate connection status indicator data, indicative of whether the disconnector device has been activated. The determining section further includes a wireless communication section which is adapted to connect to a wireless communication infrastructure using a wireless communication protocol, and to transmit the connection status indicator data over the wireless communication infrastructure.

Even when an overvoltage suppression circuit is not formed due to failure of an overvoltage suppression switch, overvoltage application to semiconductors and a filter capacitor is prevented. A control unit controls the overvoltage suppression circuit to short-circuit the filter capacitor when the voltage thereacross exceeds a predetermined value. Then when non-operation of the overvoltage suppression circuit is detected, the control unit opens an AC breaker and AC switch, and closes a charging switch. Thereafter, the control unit turns ON the converter element (or converter element) connecting to the filter capacitor terminal (or terminal) and a charging resistor, and turns ON converter element (or converter element) connecting to terminal (or terminal) of filter capacitor and connecting to the terminal of the transformer not connected to charging resistor.

The object of the invention is an overvoltage protection apparatus with monitoring function having a parallel circuit of two branch circuits, wherein the first branch circuit has a first overvoltage protection device and a second overvoltage protection device that are connected in series, wherein the second branch circuit has a third device and a fourth device that are connected in series, wherein the first overvoltage device and the third device have a first shared voltage potential during operation, and wherein the second overvoltage device and the fourth device have a second shared voltage potential during operation, wherein a first measuring tap is provided between the first overvoltage protection device and the second overvoltage protection device and wherein a second measuring tap is provided between the third device and the fourth device, with a signal being derived from the voltage between the first measuring tap and the second measuring tap that provides state information in relation to the first overvoltage protection device and the second overvoltage protection device.

A device, a method and a system for monitoring an electrical connection status of a disconnector device (110). The disconnector device (110) being connectable to pole-mounted equipment in a power distribution or transmission grid (200), thereby disconnecting the pole-mounted equipment. The connection status monitoring device (100) comprises a determining section (130) configured to determine whether the disconnector device (110) has been activated and to generate connection status indicator data, indicative of whether the disconnector device (100, 110) has been activated. The determining section (130) further comprises a wireless communication section (140) which is adapted to connect to a wireless communication infrastructure (150) using a wireless communication protocol, and to transmit the connection status indicator data over the wireless communication infrastructure (150).

An over-voltage protection system is provided for use with electrical equipment. The system includes a protection circuit having a first bus for receiving electrical power, a second bus for providing power to the equipment and two parallel surge arresters connected between the first bus and ground. A main and backup bushing are arranged in parallel between the first and second bus. The main bushing is arranged in series with a normally closed contact maintaining the main bushing in service by default. The backup bushing is arranged in series with a normally open contact isolating the backup bushing by default. The protection circuit comprises a controller for testing the insulation of the arresters and bushings. The controller is configured to selectively actuate the contacts to selectively isolate, or incorporate, the arresters and bushings in the circuit to facilitate testing and maintenance while maintaining the protection circuit operational.

A method of remotely monitoring a status of a surge arrester disconnector includes providing a long-range wireless mesh communication system including a plurality of disconnectors organized in a plurality of clusters. Each cluster includes a plurality of disconnectors that are physically located within a same cluster area. At least one of the disconnectors in each cluster is coupled to a communication device of a predetermined communication range. The method includes transmitting, from a first cluster, a status signal indicative of a status of a first disconnector in the first cluster to a second cluster located within the predetermined communication range, and consecutively transmitting the status signal from the second cluster to a third cluster within the predetermined communication range, until reaching an end cluster. The method includes transmitting, from the end cluster, the status signal to a monitoring station, and monitoring the status of the first disconnector at the monitoring station based on a result of transmission of the status signal.