Arc resistance testing of materials under various gaseous atmospheres

Electrical insulation materials exhibit a wide range of resistance to degradation under electrical arcs in normal air ambients which is well known and documented. Very little is known about the effects of discharges over dielectrics in highly insulating gaseous atmospheres such as sulfur hexafluoride (SF6). This test provides a method of categorizing this important parameter, and the effects can be measured and compared. Wet tracking tests can not be used since they are made in normal air ambient and also introduce a contaminate on the surface. Arc resistance tests are too severe and are also performed in an air atmosphere. A large selection of insulation material has been tested, graded, and reported in this paper.