Time Dependence of Breakdwon Voltage and Endurance Testing of Compressed Gas Insulation

Factors which may influence the long term endurance characteristic of gas insulated equipment are discussed in this paper. Time dependence in the dielectric strength of gas is attributed to the statistical nature of the electrical breakdown in compressed gas. The influence of the factor will diminish in large scale practical systems. Solid insulators may be subjected to deterioration, but properly fabricated gas insulated equipment is normally designed to be free from those deteriorations.