Comparative evaluation of polymer insulator materials subjected to synthetic rain

Polymer materials are currently being used as outdoor insulation for high voltage transmission and distribution lines. Work has been initiated in this laboratory to investigate the effects of natural rainfall constituents on polymeric insulator materials under high voltage conditions. In this study, high density polyethylene, silicone rubber and ethylene propylene diene monomer slabs were subjected to electric stress in a fog chamber containing an acid rain environment. It was found that all materials suffered degradation, with strong material dependencies being revealed.