Abstract: A switching arrangement for low-voltage circuit breakers with a high nominal current, comprising moveable switching contacts (2,3) arranged essentially on a moveable contact carrier (1), fixed switching contacts and a device for cooling, de-ionizing and extinguishing an electric switching arc (7, 11). The fixed contact is provided with a pre-contact function over the entire contact width thereof. Moveable contact levers (2,3) are arranged according to a set pattern in a distributed manner over the entire width of the contact carriers and are provided with or without a pre-contact (5). A contact lever (2) with a pre-contact (5) and a contact lever (3) without a pre-contact can be provided successively. Similarly, two or more contact levers (2) with a pre-contact (5), and two or more contact levers (3) without a pre-contact can be successively and alternatingly provided in packet-form.

Abstract: An arc extinguisher for low voltage switchgear, switching in air, includes a universally applicable variable attachment for adjustment of the arc extinguisher chamber to meet increased demands. The attachment is in the form of a chimney-like arc extinguisher chamber extension, for increasing the volume of the arc extinguisher chamber. It represents a moulded piece with a lower outline which exactly matches the outline of the arc extinguisher chamber cover, normally located on the arc extinguisher chamber and with an upper outline, identical to the upper outline of the switchgear housing for mounting the arc extinguisher chamber cover. Any number of attachments may be used in a stacked manner.