METHOD OF AND APPARATUS FOR VOLTAGE TESTING OF HIGH-VOLTAGE EQUIPMENT AND ELECTRICAL MACHINES

• US 3,775,686 A
• Filed: 05/24/1972
• Issued: 11/27/1973
• Est. Priority Date: 06/15/1971
• Status: Expired due to Term

• Current Assignee: Bertold Ganger, Roland Schuler
• Original Assignee: Bertold Ganger, Roland Schuler
• Inventors: Schuler, Roland, Ganger, Bertold
• Primary Examiner(s): Strecker, Gerard R.
• Application Number:
  US05/256,266
• Time in Patent Office: 552 Days
• Field of Search: 324/54
• US Class Current: 324/546
• CPC Class Codes: G01R 31/12 Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing G01R31/08, G01R31/327 and G01R31/72 take precedence; measuring in plasmas G01R19/0061; measuring dielectric constants G01R27/2617; ESD, EMC or EMP testing of circuits G01R31/002

Abstract

A method of testing the strength of insulation on electrical equipment and electrical machines at voltages higher than those to which the insulation is subjected in normal operation in which the testing is carried out under enhanced environmental conditions established by enclosing the insulated parts to be tested within a flexible transparent gas-tight envelope filled out with an electronegative gas, such as sulphur hexafluoride or Freon or other fluorocarbon based gas, or a gas/air mixture, to a pressure slightly in excess of atmospheric.

Claims

1. In the method of testing the strength of insulation of critical parts of electrical equipment and electrical machines at test voltages higher then those to which the insulation is subjected during normal operation the improvement comprising the steps of temporarily enclosing the critical insulated parts to be tested within a gas-tight envelope made from flexible transparent material, filling out said envelope with an electronegative gas or gas-air mixture to a pressure slightly in excess of atmospheric thereby to enhance the environmental conditions for the test thereafter applying the test, thereafter applying the test voltage to the critical insulated part and then removing the envelope.

2. Apparatus for testing the strength of insulation on critical parts of electrical equipment and electrical machines at test voltages higher than those to which the insulation is subjected during normal operation comprising a flexible, transparent gas-tight envelope, means supporting the insulated part to be tested within said envelope, means located exteriorly of said envelope for introducing an electronegative gas or gas/air mixture into said envelope to fill it out to a pressure slightly in excess of atmospheric, a source of test voltage located exteriorly of said envelope, and means for connecting said test voltage to the insulated part within said envelope.

3. Apparatus as defined in claim 2 for testing the strength of insulation on critical parts of electrical equipment and electrical machines and wherein said envelope is made from transparent plastic sheet material welded at the edges.