An arc quenching device creates a fault on a bus. A lockout mechanism of a circuit breaker feeding the bus is responsively actuated. Actuating the lockout mechanism may include releasing a spring-loaded mechanism mounted on a cassette that holds the circuit breaker to cause the mechanism to engage a lockout member of the circuit breaker.

A switching device including a frame, a first fixed contact member having a first contact area, and a first movable contact member having a first contact arm provided with a contact area. The first movable contact member is adapted to pivot relative to the frame around a first pivoting axis between a first position and a second position. The switching device includes a spreader member that is adapted to provide a first intermediate position for the first movable contact member in which a projection of the contact area of the first contact arm overlaps at least partially with a projection of the first contact area on a switch plane perpendicular to the first pivoting axis while the contact area of the first contact arm is spaced apart from the first contact area.

An arc quenching device creates a fault on a bus. A lockout mechanism of a circuit breaker feeding the bus is responsively actuated. Actuating the lockout mechanism may include releasing a spring-loaded mechanism mounted on a cassette that holds the circuit breaker to cause the mechanism to engage a lockout member of the circuit breaker.

The present invention provides a series compensator and a control method. The series compensator includes a series transformer, a series transformer bypass device, a voltage source converter, a high-speed converter bypass device, a high-speed switch, and a reactor. The reactor and the high-speed switch are connected in parallel to form a current limiting module; one winding of the series transformer has two ends connected in series to a line, and the other winding thereof is sequentially connected to the current limiting module and the high-speed converter bypass device; the voltage source converter and the high-speed converter bypass device are connected in parallel; and at least one winding of the series transformer are connected in parallel to at least one series transformer bypass device. The series compensator of the present invention indirectly provides the current limiting module, so as to effectively limit the short-circuit current of a system, reduce the fault current to which the compensator is subjected, and improve the reliability of an alternating current system and the series compensator. Moreover, the current limiting module has a low voltage level, and the high-speed switch has a small breaking current, thereby providing good industrial applicability.

A surge protective device (SPD) module includes a module housing, first and second module electrical terminals mounted on the module housing, a gas discharge tube (GDT) mounted in the module housing, and a fail-safe mechanism mounted in the module housing. The GDT includes a first GDT terminal electrically connected to the first module electrical terminal and a second GDT terminal electrically connected to the second module electrical terminal. The fail-safe mechanism includes: an electrically conductive shorting bar positioned in a ready position and repositionable to a shorting position; a biasing member applying a biasing load to the shorting bar to direct the shorting bar from the ready position to the shorting position; and a meltable member. The meltable member maintains the shorting bar in the ready position and melts in response to a prescribed temperature to permit the shorting bar to transition from the ready position to the shorting position under the biasing load of the biasing member. In the shorting position, the shorting bar forms an electrical short circuit between the first and second GDT terminals to bypass the GDT.

A surge protective device (SPD) module includes a module housing, first and second module electrical terminals mounted on the module housing, a gas discharge tube (GDT) mounted in the module housing, and a fail-safe mechanism mounted in the module housing. The GDT includes a first GDT terminal electrically connected to the first module electrical terminal and a second GDT terminal electrically connected to the second module electrical terminal. The fail-safe mechanism includes: an electrically conductive shorting bar positioned in a ready position and repositionable to a shorting position; a biasing member applying a biasing load to the shorting bar to direct the shorting bar from the ready position to the shorting position; and a meltable member. The meltable member maintains the shorting bar in the ready position and melts in response to a prescribed temperature to permit the shorting bar to transition from the ready position to the shorting position under the biasing load of the biasing member. In the shorting position, the shorting bar forms an electrical short circuit between the first and second GDT terminals to bypass the GDT.

An electric short-circuit device has a first electric contact piece, a second electric contact piece, and a component made of an electrical semiconductor crystalline material which blocks the flow of an electric current between the first contact piece and the second contact piece in at least one direction. An actuator is configured to apply a mechanical force to the component in response to an electric trigger signal and thereby at least partly destroy the crystalline structure of the component.

An electric short-circuit device has a first electric contact piece, a second electric contact piece, and a component made of an electrical semiconductor crystalline material which blocks the flow of an electric current between the first contact piece and the second contact piece in at least one direction. An actuator is configured to apply a mechanical force to the component in response to an electric trigger signal and thereby at least partly destroy the crystalline structure of the component.

An overvoltage protection device includes: input terminals; output terminals; at least two overvoltage protection elements for forming staggered protection levels; and at least one longitudinal element electrically connecting an input terminal and an output terminal to conduct an operating current. In order to form a first protection level, a first overvoltage protection device is connected to two input terminals on an input side upstream of the at least one longitudinal element, and, in order to form a second protection level, a second overvoltage protection element is connected to two output terminals on an output side and downstream of the at least one longitudinal element, the at least one longitudinal element influencing a response of the at least two overvoltage protection elements in case of an overvoltage. The at least one longitudinal element is provided with a thermal overload protection device for reducing a possible current flow.

An overvoltage protection device includes: input terminals; output terminals; at least two overvoltage protection elements for forming staggered protection levels; and at least one longitudinal element electrically connecting an input terminal and an output terminal to conduct an operating current. In order to form a first protection level, a first overvoltage protection device is connected to two input terminals on an input side upstream of the at least one longitudinal element, and, in order to form a second protection level, a second overvoltage protection element is connected to two output terminals on an output side and downstream of the at least one longitudinal element, the at least one longitudinal element influencing a response of the at least two overvoltage protection elements in case of an overvoltage. The at least one longitudinal element is provided with a thermal overload protection device for reducing a possible current flow.