Physical and chemical characterization of polymer housed surge arresters tested under accelerated weathering

In our investigation we tested two arresters with different polymeric housing material; the basic polymer of one arrester is silicon rubber (SiR), and ethylene propylene diene monomer (EPDM) for the other one. They were tested under accelerating aging and multistress conditions with environmental cycles, representative of the specific conditions in the most severe locations of Mexico. We report the use of static contact angle measurement and microstructure observation on the insulating material surface to diagnose the insulation condition. It is important to note that these techniques also proved to have effectiveness as non-destructive techniques to be used with polymeric insulation being in service. Special attention is taking on non destructive microstructure observation technique by using the replica technique widely used in metallurgy.