Gas filled HV switching appts. - has blind to shield viewing window when circuit is broken to prevent deposition of dirt on inside

摘要

The appts. is used for shielding a window (8) in a housing (1) of a HV switch. It comprises a blind (9) which is operated automatically by a lever (13) on the inside of the gas-filled housing (1). The blind can also be operated by an external lever (6) or simultaneously from the inside and the outside. The window provides a view of the electric contacts (3, 4) and it is not rendered opaque when the gas (e. g. SF6) is decomposed by an electric arc.