Field testing of silicone rubber compositions

In this paper the design of the facility (power supply and leakage current (LC) measuring system) and experience from first 12 months of aging on 4 compositions of high temperature vulcanized (HTV) silicone rubber (SIR) are reported. Samples were selected according to a 2³ factorial test plan, where electrical stress, content of ATH-filler and content of silicone oil were the factors. A high filler level significantly increased the leakage current activity on AC energized insulators. Short DC energized insulators show already traces of erosion, the erosion are more pronounced for samples with extra silicone oil