A low-voltage circuit breaker includes at least one current sensor for determining the magnitude of the electric current of a conductor of the low-voltage circuit breaker; and at least one electromechanical switching unit for connecting and disconnecting at least two electrical contact points. In a first switching position of the movable contact point, two contact points are connected and in a second switching position the contact points are not connected to one another. The circuit breaker further includes at least one electronic switching unit having a semiconductor switching element, electrically conductive in a first switching state and electrically blocking in a second switching state; an electronic tripping unit, connected to the current sensor, the electronic switching unit and the electromechanical switching unit. Further, when current and/or current/time-period limit values of the conductor are exceeded, first the electromechanical switching unit is opened and then the electronic switching unit is blocked.

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.

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.

Switch assemblies and switching methods are disclosed. In some embodiments, a switch assembly may include a first blade having a first contact within an enclosed cavity, and a second blade having a second contact within the enclosed cavity. The first and second contacts are operable to make or break contact with one another in response to a magnetic field. The switch assembly may further include a coating formed over each of the first and second contacts, the coating including a titanium layer, a second layer formed over the titanium layer, and a tungsten-copper layer formed over the second layer. In some embodiments, the second layer is copper or molybdenum.

Switch assemblies and switching methods are disclosed. In some embodiments, a switch assembly may include a first blade having a first contact within an enclosed cavity, and a second blade having a second contact within the enclosed cavity. The first and second contacts are operable to make or break contact with one another in response to a magnetic field. The switch assembly may further include a coating formed over each of the first and second contacts, the coating including a titanium layer, a second layer formed over the titanium layer, and a tungsten-copper layer formed over the second layer. In some embodiments, the second layer is copper or molybdenum.

A system for isolating a fault in a direct current (DC) grid using thermionic arc extinction. The system includes a DC grid that includes a transmission line. The DC grid also includes a plurality of current interrupters disposed on the transmission line. Each of the plurality of current interrupters on the transmission line are electrically coupled to one another in series. At least one of the current interrupters includes a fixed terminal end and a moveable terminal end. Further, at least one of the current interrupters has an arc shield housing at least two arcing contacts. At least one of the arcing contacts comprises a first conducting material that has a first vaporizing point.

A system for isolating a fault in a direct current (DC) grid using thermionic arc extinction. The system includes a DC grid that includes a transmission line. The DC grid also includes a plurality of current interrupters disposed on the transmission line. Each of the plurality of current interrupters on the transmission line are electrically coupled to one another in series. At least one of the current interrupters includes a fixed terminal end and a moveable terminal end. Further, at least one of the current interrupters has an arc shield housing at least two arcing contacts. At least one of the arcing contacts comprises a first conducting material that has a first vaporizing point.

A vacuum interrupter includes a housing having at least one annular ceramic insulating element which forms a vacuum chamber. A contact system has two contacts which are movable relative to one another. A capacitive element has two electrodes and a dielectric material disposed between the electrodes. The capacitive element is form-lockingly mounted on the insulating element and has a capacitance between 400 pF and 4000 pF. A high-voltage switching assembly including the vacuum interrupter is also provided.

A safety device for emergency shut-down of an electric instantaneous water heater. The safety device includes a contact and a counter contact, which are set up to conduct the current for supplying the instantaneous water heater in a contacted state and to interrupt the power supply of the instantaneous water heater in an open state. Further, the safety device includes a mounting device for mounting the counter contact on a tie rod, wherein the tie rod is set up to release the mounting device and the counter contact 4 from the contact to interrupt a power supply of the instantaneous water heater. The contact of the safety device is implemented as a contact rivet which is integrated directly into a circuit board.

Various embodiments of the teachings herein include a grid influencing system for a power supply grid comprising: a current-conducting grid influencing component; and a vacuum circuit breaker including a vacuum circuit breaker tube containing an at least partly integrated pre-arcing device for actively generating an arc between two contacts.