Abstract: A method for operating a circuit-breaker by means of which one is able by using a vacuum circuit-breaker, to interrupt inductive circuits without causing disturbing overvoltages. The switching operation of the vacuum circuit-breaker is influenced by a tripping control device, which is supplied with a measured value of the tripping delay of the vacuum circuit-breaker from the instant the tripping signal is output to the instant the contact members are separated as a correcting quantity, in the case of an opening operation that occurred previously. The temperature of the actuator unit of the vacuum circuit-breaker, the standstill time of the circuit-breaker, as well as the operating voltage and temperature of a tripping solenoid can be used as further correcting quantities. The described method is suited for application vacuum circuit-breakers in circuits with inductive components.

Abstract: A disconnect switch for use with a metal-encapsulated high-voltage switching installation wherein the switch comprises a movable switching pin and a mating contact axially associated therewith. The switch is further provided with a tube of insulating material arranged in surrounding sliding relationship to the switching pin and with a spring means braced against the pin for applying a force to the tube. Latching means is also provided for latching the tube against the force of the spring means in the on and off positions of the switch. The latter means further cooperates with an unlatching means which, during the course of the movement of the switching pin to close the switch, releases the latching means, thereby causing the tube to bridge the gap between the mating contact and the pin before the latter elements make metallic contact.

Abstract: The invention is directed to a quenching and contact arrangement for a compressed-gas circuit breaker. The arrangement includes a tubular contact piece and a contact piece axially arranged therewith. An arc is drawn between both contact pieces when the circuit is interrupted under load, the arc then being blasted by a stream of compressed-gas. A turbulence grid is arranged in the flow path of the stream. The turbulence grid is configured in the form of a tube of insulating material with perforations in the cylinder surface thereof which directly encloses the arcing space in the course of the circuit-breaking motion.

Abstract: A contact arrangement for a vacuum switch includes contacts which have central contact surfaces and arc running surfaces surrounding the central contact surfaces. Means are provided to direct current to the area of the central contact surfaces as well as to the area of the arc running surfaces. As the arc foot points approach the edge of the contacts, forces become effective which prevent the arc from leaving the area between the contacts.