An on-load tap-changer of a tap-changing transformer has a switch. The switch has: a take-off contact; a primary fixed contact; and a contact unit. The contact unit has a moving contact, a first arcing contact and a second arcing contact. These contacts are pivotable about a pivot axis during a switchover process such that the contacts assume a first position, in which they make contact with the take-off contact and the primary fixed contact, and a second position, in which they are separated from the take-off contact and the primary fixed contact. The second arcing contact assumes the first position before the first arcing contact when switching over from the second position to the first position and leaves the first position after the first arcing contact when switching over from the first position to the second position.

An on-load tap-changer of a tap-changing transformer has a switch. The switch has: a take-off contact; a primary fixed contact; and a contact unit. The contact unit has a moving contact, a first arcing contact and a second arcing contact. These contacts are pivotable about a pivot axis during a switchover process such that the contacts assume a first position, in which they make contact with the take-off contact and the primary fixed contact, and a second position, in which they are separated from the take-off contact and the primary fixed contact. The second arcing contact assumes the first position before the first arcing contact when switching over from the second position to the first position and leaves the first position after the first arcing contact when switching over from the first position to the second position.

A medium voltage switching pole includes: a fixed contact of a vacuum interrupter; a movable contact of the vacuum interrupter; a piston; at least one electrical contact; a first terminal; and a second terminal. The fixed contact is fixedly connected to the first terminal. The movable contact is fixedly connected to the piston. The piston moves within the second terminal along an axis. The at least one electrical contact makes an electrical connection between the piston and the second terminal. An outer surface of the piston and an inner surface of the second terminal are arranged such that: when in an open configuration the fixed contact and movable contact are separated, at least one first radial line perpendicular to the axis extends through locations of the at least one electrical contact, and a first distance along the at least one first radial line extends from the outer surface.

A circuit breaker for connecting at least two line sections in an interruptible manner has at least one pair of vacuum tubes, each with a stationary switching contact and a movable switching contact. The switching contacts of the vacuum tubes are electrically connected in series. The movable switching contacts of the vacuum tubes are coupled to a common actuator and can be simultaneously switched by a movement of the actuator.

In a vacuum container (1) of a vacuum interrupter (1A), an insulating cylindrical body (10) is sealed with a fixed-side flange (11a) on the fixed side in the axial direction, and is sealed with a movable-side flange (11b) on the movable side in the axial direction. In the fixed-side flange (11a) and the movable-side flange (11b), annular expansion portions (5a, 5b) are formed between middle portions (3a, 3b) and outer peripheral edge portions (4a, 4b), respectively. The annular expansion portions (5a, 5b) are respectively formed in annular shapes extending along the outer peripheries of the middle portions (3a, 3b), and in shapes expanding in the axial outer side direction of the vacuum container (1), such that an arch structural effect can be obtained.

A switch including a first electrical terminal, the first electrical terminal including a blade pivotable between an open position and a closed position, and a rod extending from the first electrical terminal parallel to the blade. The switch further includes a second electrical terminal configured to receive the blade when in the closed position, the second electrical terminal including a vacuum interrupter, wherein the vacuum interrupter engages the rod when in the closed position. Rotating the first electrical terminal in a first direction causes the blade to disengage from the second electrical terminal at a first point, and further rotating the first electrical terminal in the first direction causes the rod to disengage from the vacuum interrupter at a second point.

A switch including a first electrical terminal, the first electrical terminal including a blade pivotable between an open position and a closed position, and a rod extending from the first electrical terminal parallel to the blade. The switch further includes a second electrical terminal configured to receive the blade when in the closed position, the second electrical terminal including a vacuum interrupter, wherein the vacuum interrupter engages the rod when in the closed position. Rotating the first electrical terminal in a first direction causes the blade to disengage from the second electrical terminal at a first point, and further rotating the first electrical terminal in the first direction causes the rod to disengage from the vacuum interrupter at a second point.

In a vacuum valve, as a heat dissipation structure thereof, a heat dissipation layer is provided to a part of the surface of each of a fixed conductor and a movable conductor which are a heat generation part, and a radiation heat absorption layer is provided to an insulation cylinder so as to be opposed to the heat dissipation layer. The heat dissipation layer and the radiation heat absorption layer are each formed from a ceramic having a high emissivity. Heat generated at the fixed conductor and the movable conductor is radiated by the heat dissipation layer, to be absorbed by the radiation heat absorption layer, and then radiated to the outside of the vacuum valve from the radiation heat absorption layer and a ceramic layer.

A circuit breaker includes a capacitive voltage sensor located within its insulating casing. The voltage sensor includes a capacitor located between the terminals of the circuit breaker adjacent a low potential surface provided by a coil of a current sensor. The capacitor is dome shaped. The voltage sensor does not appreciably increase the size or weight of the circuit breaker and is reliable and accurate.

A circuit breaker includes a capacitive voltage sensor located within its insulating casing. The voltage sensor includes a capacitor located between the terminals of the circuit breaker adjacent a low potential surface provided by a coil of a current sensor. The capacitor is dome shaped. The voltage sensor does not appreciably increase the size or weight of the circuit breaker and is reliable and accurate.