The invention relates to an overvoltage protection device with a short-circuit function for protecting installations and persons for low-voltage installations, wherein at least one overvoltage protection element and a thermally activatable short-circuit device are arranged in a common housing. The device is designed to be inserted into an NH fuse part, and the common housing is designed with contact blades so as to be spatially analogous to a NH fuse link.

A bypass switch includes: a casing; a vacuum interrupter disposed inside the casing, the vacuum interrupter being disposed such that a movable contact is movable to a fixed contact; a first fixing bus-bar fixed to the casing; a second fixing bus-bar fixed to the casing to be spaced apart from the first fixing bus-bar; a moving pusher connected to the movable contact; a drive source installed in the casing, the drive source pushing the moving pusher to a position at which the movable contact and the fixed contact are contacted with each other; and a multi-contactor disposed to be contacted with the moving pusher. Accordingly, the moving pusher can rapidly contact the movable contact with the fixed contact. Further, the moving pusher can be moved with a small external force. Thus, it is possible to minimize the size of the drive source and the power used in the drive source.

An electrical short-circuiting device includes a fixed contact piece and a movable contact piece. The fixed and movable contact pieces are distanced from one another in a basic position and electrically conductively connected to one another in a short-circuit position. A drive transfers the movable contact piece from the basic position into the short-circuit position, and a trigger device includes an electrically driven actuator for triggering the drive.

Certain aspects are directed to a thermal fuse for preventing overheating of RF devices in a telecommunication system. In one embodiment, an RF thermal fuse comprises a body: a conductive bolt positioned in the body, the conductive bolt having a length sufficient to provide an impedance at a point of protection on a transmission line in response to the conductive bolt contacting a live conductor of the transmission line, wherein the impedance reflects a portion of the incident power of an RF signal from an RF signal source; and a driving mechanism that causes the conductive bolt to selectively contact the live conductor in response to an event.

Certain aspects are directed to a thermal fuse for preventing overheating of RF devices in a telecommunication system. In one embodiment, an RF thermal fuse comprises a body: a conductive bolt positioned in the body, the conductive bolt having a length sufficient to provide an impedance at a point of protection on a transmission line in response to the conductive bolt contacting a live conductor of the transmission line, wherein the impedance reflects a portion of the incident power of an RF signal from an RF signal source; and a driving mechanism that causes the conductive bolt to selectively contact the live conductor in response to an event.

An electrical short-circuiting closing switch including an electrically insulating housing; a first electrode having a tapered first electrode opening; a second electrode having a tapered second electrode opening; a movable contact having a tapered profile, the movable contact being movable relative to the housing along a closing axis from an open position, in which the movable contact is electrically disconnected from the second electrode, to a closed position, in which the movable contact electrically connects the first electrode and the second electrode by engaging the tapered profile with the first electrode opening and the second electrode opening; and an actuator arranged to force the movable contact from the open position to the closed position; wherein at least one of the first electrode and the second electrode is flexibly attached to the housing. A switchgear including a closing switch is also provided.

An electric closer, in particular for a motor vehicle line, in particular a motor vehicle power line, comprising a first electrical terminal and a second electrical terminal, a first contact element which is electrically connected to the first terminal, a second contact element which is electrically connected to the second terminal, a connecting element with which an electrical connection can be established between the two contact elements, and a drive which effects a relative movement between the contact elements and connecting element, characterised in that the connecting element or the contact elements are formed at least in parts from an electrically conductive, porous metal.

A short circuit current detection device for a medium voltage or high voltage switchgear includes: a reed contact; and a holder for holding the reed contact, the holder being mountable with a defined orientation to a conductor of the switchgear. At a location where the holder is mounted, the conductor has a longitudinal axis. The conductor enables a current to flow through the conductor in a direction of the longitudinal axis. The holder positions the reed contact with respect to the longitudinal axis such that when a magnitude of the current flow through the conductor exceeds a threshold current value the reed contact closes.

An electric system has an electrical energy source connected to an electrical energy sink by at least one feeding line. Each feeding line (8) is in at least one position therealong between said source and said sink provided with an arrangement configured to interrupt arcing in the feeding line would such arcing reach this position. The arrangement has a temperature dependent member which upon an increase of the temperature thereof above a predetermined level activates an irreversible movement of movable means (24) which by this movement cuts off the arc (a) and/or removes hot ionized gases (28) and by that prevents the arcing to continue in the feeding line past the arrangement.

The invention relates to a switching device, in particular for a voltage limiting device, which has a first fixed switching contact 14 which is electrically connected to a first device terminal 8, a second fixed switching contact 15 which is electrically connected to a second device terminal 9, and a movable switching contact 16. The invention also relates to a voltage limiting device which has such a switching device 5. The first and second fixed switching contacts 14, 15 of the switching device are arranged next to one another in such a way that their contact surfaces 14A, 15A point in the same direction. The movable switching contact 16 can be moved between a closed position in which the first and second fixed switching contacts 14, 15 are electrically connected to one another, and an open position in which the first and second fixed switching contacts 14, 15 are separated from one another. The first and second fixed switching contacts 14, 15 and the movable switching contact 16 form an arrangement of electrical conductors which are arranged substantially parallel to one another. At least one of the fixed switching contacts 14, 15 has an elongated contact surface which extends in the direction A of current flow. Electrodynamic forces act on the fixed conductors 14, 15 and the movable conductor 16, which are directed in such a way that the conductors attract each other, i.e., the switching contacts tend to close.