Abstract: A new vacuum switching chamber is intended for power breakers in the low-voltage range and is distinguished by a compact form with a small physical height and a high switching capacity. Its enclosure includes a plate-like power current connection, a cylindrical wall part which surrounds flat spiral contacts, an annular insulator and a membrane disk with a centrally arranged power current supply bolt.

Abstract: A movable contact arrangement suitable for use in a switching device has a rigid contact body and a flexible conductor piece connecting the contact body to a fixed conductor. The contact body is connected to the conductor piece by mechanically compressing a section of a semifinished product in the form of a cable or strand, with the flexible conductor piece being formed by an uncompressed part of the semifinished product. The compressing operation can also be used at the same time to produce the contact body from the semifinished product. The method described allows low-cost production of contact modules for power circuit breakers used in sophisticated mechanical and electrical equipment.

Abstract: A low-voltage circuit breaker (1) has an arc-extinguishing chamber (2) and a switching gas damper (4) which consists of two partial bodies (6, 7) that are displaceable in relation to each other. One (6) of the partial bodies (6, 7) is fixed to the circuit-breaker (1), while the other (7) is pre-stressed against the first partial body (6) with an elastic restoring force (spring 12). The switching gases that; are discharged from the arc-extinguishing chamber (2) are contained inside (8) the switching gas damper (4) until the relative displacement of the partial bodies (6, 7) forms a flow outlet through which the switching gases can escape.

Abstract: A low voltage circuit breaker (1) has an arc extinguishing chamber (2) and a switching gas damper (4) which consists of two partial bodies (6, 7) that are displaceable in relation to each other. One (6) of the partial bodies (6, 7) is fixed to the circuit-breaker (1), while the other (7) is pre-stressed against the first partial body (6) with an elastic restoring force (spring 12). The switching gases that are discharged from the arc-extinguishing chamber (2) are contained inside (8) the switching gas damper (4) until the relative displacement of the partial bodies (6, 7) forms a flow outlet through which the switching gases can escape.

Abstract: In switchgear with superordinate power circuit-breakers and a plurality of subordinate power circuit-breakers, the superordinate power circuit-breaker must be triggered in the event of failure of the subordinate power circuit-breakers. This is accomplished as follows: electrical post-arc currents are detected after current zero, the electrical post-arc currents are compared with a predetermined limit value, and if the limit value is exceeded, a signal is effected for triggering the superordinate power circuit-breaker in the switchgear. This method can advantageously be implemented in particular in the case of vacuum circuit-breakers with at least one vacuum interrupter. The associated arrangement has a device which monitors the subordinate power circuit-breakers and, if appropriate, triggers the superordinate power circuit-breaker.

Abstract: A contact system for power circuit breakers includes a nozzle body made of graphite which is pressed cold into a tube of cold-worked copper and is enclosed by the latter with a friction fit. A low-alloy copper is used as the material for the electrically conducting tube. Such a copper alloy can be made, for example, with 0.1 percent silver.