Characteristics of EHV Station Post Insulators

Results of tests and research are given covering EHV station post insulators from 1,300 BIL (basic insulation level) to 2,100 BIL, including flashover and withstand on 60 cycle wet and dry, impulse and switching surge, wet and dry tests. As of today there is no information such as this in the literature. Since several United States and Canadian systems are now in the midst of 500and 700-kv substation design, the information should be timely. Some data are inconclusive and will have to be verified or varied by additional testing. Other data are presented to show trends rather than final results.