Method and equipment for vacuum monitoring in vacuum switching tubes

US4906935A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Ruediger Hess · Berlin, DE
• Wilfried Kuhl · Wendelstein, DE
• Leonhard Klug · Erlangen, DE
• Wolfgang Schilling
• Peter Trentin · Gustavsburg, DE
• Heribert Weber · Leverkusen, DE
• Wolfgang Schlenk · Erlangen, DE
• Heinz-Helmut Schramm · Berlin, DE

Key dates

• Filing date: Sep 29, 1988
• Grant date: Mar 6, 1990
• Expiry date: Sep 29, 2008

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01H33/668
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

To check the presence of operating vacuum in vacuum switches, high voltage can be applied between the contacts at a given contact spacing and the dielectric strength can be tested. According to the invention, the procedure for vacuum monitoring is that a contact spacing (h) below the nominal stroke of the vacuum switch is selected and that the X-radiation generated at this contact spacing (h) and high voltage (U) in vacuum due to the field electron emission between the contacts by the contact surfaces acting as anode is acquired and evaluated as proof of the presence of operating vacuum inside the switching tube. This method can preferably be applied to encapsulated vacuum switching tubes, in particular to SF.sub.6 -insulated switching facilities. Associated with the vacuum switching tube (15) in the associated equipment is an X-ray detector, preferably a Geiger-Muller counter, which is connected to the high-voltage unit (25) via an evaluating circuit (30 to 50) which serves for the determination and indication of the operating vacuum and shuts off the high-voltage unit (25) to minimize the X-ray dose. Due to the X-ray emission, which is stopped long before reaching impermissible v…