Abstract: An actuator system for actuating a high voltage current interrupter is disclosed. The actuator system comprises a transmission link for transmitting kinetic energy from a force provision system to a moveable contact of the current interrupter. The transmission link has a first end which is mechanically connectable to the moveable contact of the current interrupter and a second end facing away from the moveable contact. The actuator system further comprises a damping system comprising a shock-absorbing mass. The shock-absorbing mass is located along the extension of the line of translational movement of the transmission link, at the farther side of the transmission link as seen from the current interrupter, so that upon an opening operation of the current interrupter, the second end of the transmission link will collide with the shock-absorbing mass.

Abstract: An actuator system for actuating a high voltage current interrupter is disclosed. The actuator system comprises a transmission link for transmitting kinetic energy from a force provision system to a moveable contact of the current interrupter. The transmission link has a first end which is mechanically connectable to the moveable contact of the current interrupter and a second end facing away from the moveable contact. The actuator system further comprises a damping system comprising a shock-absorbing mass. The shock-absorbing mass is located along the extension of the line of translational movement of the transmission link, at the farther side of the transmission link as seen from the current interrupter, so that upon an opening operation of the current interrupter, the second end of the transmission link will collide with the shock-absorbing mass.

Abstract: The protective device for protecting against over currents in electric circuits includes at least one electrically conductive body and two electrodes which function to supply circuit current through the conductive body and which lie against the conductive body at corresponding positions either directly or through the medium of an intermediate part. An abutment pressure is applied to the electrode so that the electrodes are maintained in abutment at the corresponding positions of the conductive body. When the devices are subjected to high short circuiting currents, the current density in the deformed abutment surfaces of the conductive body will increase, thus increasing the resistance of the device.

Abstract: A PTC element has at least one body and two electrodes. The body or bodies has/have and is/are two parallel surfaces, of an electrically conductive polymer composition with a positive temperature coefficient. At least one of the parallel surfaces on the body, or on one of the bodies, of polymer composition is in free contact with an electrode or with a parallel surface on another body of electrically conductive polymer composition. A pressure device exerts a pressure directed perpendicularly to the parallel surfaces on the body, or the bodies, on the electrodes. The pressure device is preferably provided with pressure-exerting devices with the ability to be resilient. After changing from a low resistance to a high resistance state, the PTC element returns to the initial resistance and is reusable after having been subjected to short-circuit currents. The parallel surfaces on the body, or the bodies, of polymer composition may be concentric.

Abstract: A device for motor and short-circuit protection in low-voltage plants includes a contact device (3) which is connected in series with a tripping circuit comprising two parallel-connected current branches. One of the branches comprises a first thermistor (1) serving as an overload protective means and connected in series with a second thermistor (2) serving as a short-circuit protective means. The second branch comprises a multi-turn excitation coil (4) which is adapted to influence the contact device (3) for opening thereof at an overcurrent. The resistivity of the two thermistors (1, 2) has a positive temperature coefficient in the temperature range in question. The first thermistor (1) may consist of a ceramic material or electrically conductive polymer composite. The second thermistor (2) consists of polymer composite with a extremely high content of electrically conductive filler and is, in addition, layered.