A switch-fuse module and a ring main unit. The switch-fuse module includes: a housing having therein a first enclosure including a first insulating gas and a second enclosure including a second insulating gas; at least one switch disconnector arranged within the first enclosure; and at least one fuse at least partially surrounded by the second enclosure; wherein each of the first insulating gas and the second insulating gas has a global warming potential less than a global warming potential of SF6, and the first enclosure is different and separate from the second enclosure.

A switch-fuse module and a ring main unit. The switch-fuse module includes: a housing having therein a switch enclosure including an insulating gas and a cable compartment that is different and separate from the switch enclosure; at least one switch disconnector arranged within the switch enclosure; and at least one fuse canister with a vertically oriented longitudinal axis; wherein the fuse canister i) is adapted to receive a fuse, and ii) is arranged within the cable compartment, and the insulating gas has a global warming potential less than a global warming potential of SF6.

A switch-fuse module and a ring main unit. The switch-fuse module includes: a housing having therein a switch enclosure including an insulating gas and a cable compartment that is different and separate from the switch enclosure; at least one switch disconnector arranged within the switch enclosure; and at least one fuse canister with a vertically oriented longitudinal axis; wherein the fuse canister i) is adapted to receive a fuse, and ii) is arranged within the cable compartment, and the insulating gas has a global warming potential less than a global warming potential of SF6.

A high voltage electric switch includes contacts with graphite carbon electrode forming the arc gap. In addition, the carbon contacts are located in a chamber containing at least 60% carbon dioxide (CO2) as a dielectric gas to achieve improved arc interrupting performance. In conventional switches, the metallic contacts introduce metallic vapors into the arc plasma that inhibits the ability of the dielectric gas to interrupt high voltage, high current arcs. As the element carbon is inherently present in CO2 gas, the addition of vapors from the carbon electrodes into the dielectric gas does not significantly interfere with the dielectric arc-interrupting performance of the CO2 dielectric gas.

An electromechanical actuator includes an electrically insulating rod, an electrically insulating cover at least partly encompassing the electrically insulating rod, and an elastomeric diaphragm. The electrically insulating rod has a body, a first actuation portion connected to an electromechanical drive mechanism arranged in a first region, and a second actuation portion for actuating an electromechanical actuation mechanism arranged in a second region. The elastomeric diaphragm unit is arranged between the body and the cover. The elastomeric diaphragm unit has a flexible membrane electrically separating the first region from the second region. The elastomeric diaphragm unit is coated on at least one surface of the membrane with a semiconductive layer.

A gas circuit breaker includes: a fixed arc contact disposed on an axis of motion, whose tip is directed to one side in a first direction that is parallel to the axis of motion; a movable arc contact that can reciprocate along the axis of motion between a position when in contact with the tip of the fixed arc contact and a position when separated from the tip of the fixed arc contact; and a first permanent magnet and a second permanent magnet as a permanent magnet whose magnetic poles are aligned in a second direction that is a direction perpendicular to the first direction. The fixed arc contact has a shape that is gradually widened in a direction away from the axis of motion from the tip toward another side in the first direction.

A gas circuit breaker includes: a fixed arc contact disposed on an axis of motion, whose tip is directed to one side in a first direction that is parallel to the axis of motion; a movable arc contact that can reciprocate along the axis of motion between a position when in contact with the tip of the fixed arc contact and a position when separated from the tip of the fixed arc contact; and a first permanent magnet and a second permanent magnet as a permanent magnet whose magnetic poles are aligned in a second direction that is a direction perpendicular to the first direction. The fixed arc contact has a shape that is gradually widened in a direction away from the axis of motion from the tip toward another side in the first direction.

The use of a gas as a medium for electrically isolating and/or extinguishing electric arcs, the gas including 1-chloro-2,3,3,3-tetrafluoropropene. Also, an electrical device including a sealed chamber containing electrical components and a gas for electrically isolating and/or extinguishing electric arcs, in which the gas includes 1-chloro-2,3,3,3-tetrafluoropropene. The gas may be only 1-chloro-2,3,3,3-tetrafluoropropene.

A gas-insulated switching device including, inside a pressure tank: a vacuum valve having a movable contact provided on one side of a movable conductor, and a fixed contact provided to a fixed conductor; an insulation rod connected to another side of the movable conductor led out through a bellows from the vacuum valve; and an airtight container in which the insulation rod and the other side of the movable conductor are stored, wherein an internal space of the bellows and an internal space of the airtight container communicate with each other, one side of the vacuum valve is fixed to a tank wall via an insulation support body, another side of the vacuum valve is connected to the tank wall via the airtight container, and the airtight container insulates the vacuum valve and the tank wall from each other, and is slidable in a movable direction of the movable conductor.

A gas circuit breaker includes: a fixed arc contact disposed on an axis of motion, whose tip is directed to one side in a first direction that is parallel to the axis of motion; a movable arc contact that can reciprocate along the axis of motion between a position when in contact with the tip of the fixed arc contact and a position when separated from the tip of the fixed arc contact; and a first permanent magnet and a second permanent magnet as a permanent magnet whose magnetic poles are aligned in a second direction that is a direction perpendicular to the first direction. The fixed arc contact has a shape that is gradually widened in a direction away from the axis of motion from the tip toward another side in the first direction.