Evaluation of polymer systems for outdoor HV insulator application by salt fog chamber testing

This paper describes the development of a functional test method to evaluate the long term performance of are resistant polymer compounds in their function as insulator sheds on longrod insulators. Cylindrical rod samples are subjected to cyclic conditions of salt fog and high voltage stresses. The surface discharge and current conditions are monitored by continuous digital current measurements. The results of the fog chamber testing are compared to actual service experience under outdoor contaminated conditions.