Main Article Content
Pollution of high voltage insulators is a problem for outdoor substation installations as in the case of transmission lines. Composite materials can provide a solution in this case also. However there are limitations especially for the already installed equipment, where the use of composite housings is not technically or financially in profit for the electrical utility. RTV SIR coatings are an efficient alternative in this case, since they can demonstrate a behavior similar to a composite insulator and in the same time can be applied on the already installed equipment. In this paper the performance of coatings installed in a coastal high voltage substation is investigated by measurements of leakage current. The measurements indicated the improvement achieved by the use of coatings and further reveal the importance of the wetting mechanism, for these specific environmental conditions.