Abstract: A voltage surge protection device for protection of a high voltage device includes a varistor having a first part and a second part separated by varistor material. The voltage surge protection device further includes an expandable member arranged to act on a movable electrical contact for short-circuiting the voltage surge protection device upon a threshold voltage being applied between the first part and the second part of the varistor. A high voltage circuit breakers includes one or more semiconductor devices connected in series and the voltage surge protection device connected in parallel thereto.

Abstract: A voltage surge protection device for protection of a high voltage device includes a varistor having a first part and a second part separated by varistor material. The voltage surge protection device further includes an expandable member arranged to act on a movable electrical contact for short-circuiting the voltage surge protection device upon a threshold voltage being applied between the first part and the second part of the varistor. A high voltage circuit breakers includes one or more semiconductor devices connected in series and the voltage surge protection device connected in parallel thereto.

Abstract: A circuit breaker for high voltage applications, including: at least one breaking unit, a supporting insulator having one end on ground potential and the other end on high voltage potential, and the end on high voltage potential is mechanically connected to the breaking unit, and a fiber optic sensor for sensing the current through the breaking unit. The supporting insulator is removably connected to the breaking unit. The sensor has an optic fiber coil arranged in the high voltage end of the supporting insulator, and the circuit breaker includes a mechanism for conducting current from the breaking unit to the sensor so that the current passes through the sensor coil.

Abstract: A circuit breaker for high voltage applications, including: at least one breaking unit, a supporting insulator having one end on ground potential and the other end on high voltage potential, and the end on high voltage potential is mechanically connected to the breaking unit, and a fiber optic sensor for sensing the current through the breaking unit. The supporting insulator is removably connected to the breaking unit. The sensor has an optic fiber coil arranged in the high voltage end of the supporting insulator, and the circuit breaker includes a mechanism for conducting current from the breaking unit to the sensor so that the current passes through the sensor coil.

Abstract: The invention relates to a system and a method for assembly and maintenance of connection modules (3) in high-voltage switchgear (1). According to the invention assembly and maintenance are performed in a service bay (6) in the vicinity of the switchgear. Modules (3a) to be assembled, replaced or repaired are transported between the service bay (6) and its site (2a) in the switchgear area by a service vehicle (4). The vehicle (4), connection modules (3) and the positions for their base plates (2) are thus so adapted to each other that the service vehicle (4) can move about in the switchgear area while the switchgear is in operation. A special aspect of the invention is the custom-design of the service vehicle (4) specifically for its purpose.

Abstract: A system for assembly and maintenance of connection modules in a high-voltage switchgear. The assembly and maintenance is performed in a service bay in the vicinity of the switchgear. Modules which are to be assembled, replaced or repaired are transported between the service bay and the site in the switchgear area by a service vehicle. The vehicle, the connection modules and the positions for the base plates are so adapted that the service vehicle can move about in the switchgear area while the switchgear is in operation. A special aspect of the invention is the special design of the service vehicle.

Abstract: A truck mounted breaker for high voltage lines. The breaker is a kind in which a linear displaceable contact device, including a plurality of units, coacts with a stationary countercontact device which includes a corresponding number of countercontact units. The breaker is intended for high voltage lines. All countercontact units are supported by a stand common to the units. The stand also supports the linear displaceable contact device. This arrangement ensures correct alignment of all pairs of contact and countercontact units.

Abstract: A switch assembly for high voltage overhead lines. The assembly includes circuit breakers with associated operators and circuit disconnectors with associated operators. These are supported by a stand. This switch assembly construction reduces the amount of space required by the switch gear and simplifies the erection of the switch gear. The stand has a single support base which supports all components of the switch assembly.