Vacuum Arc Extinguishing Chamber KDV4-35-25/1600 for Electrical Switching Applications

Vacuum arc suppression chamber is the heart of vacuum switching apparatus for various purposes. Its design includes the following main elements: contacts, current leads, screens, insulating casing. The contact group works in the following way: the current is fed to the contacts through inductors, which have the form of two semicircles.

The axial field arising during such current flow keeps the arc in a diffuse state and prevents its ejection beyond the contacts. It allows to increase the reserve on the switch-off current and to reduce the thermal load on the screens. At opening of the current circuit by the VDC contacts, a vacuum arc lights up, which goes out when the switched off alternating current passes through zero value.

Properties of the arc and efficiency of its switching off depend on the distance between the contacts, speed of their opening, current value, material and design of the contacts.