Evaluation of a New Protective Coating for Porcelain Insulators
This paper describes the evaluation of a new elastomeric coating made from a silicone rubber compound for use on porcelain insulators. Field experience has shown that coated insulators have a lower flashover probability under wet contaminated operation than uncoated insulators.
RTV silicone rubber coatings for substation insulator maintenance
The selection, application, and performance of room-temperature-vulcanizing (RTV) silicone rubber coatings for the maintenance of electrical substation insulators are described. The ability of silicone rubber coatings to suppress leakage current, thereby eliminating the cause of electrical power interruptions to the plant, is discussed. Coating life expectancy is discussed in terms of the pollution conditions, the frequency of maintenance cleaning, and the formulation of the RTV silicone rubber coating system.<<ETX>>
Switching Surge Performance of Contaminated Insulators
The "wet contaminant" test method, originally developed for use with alternating voltage, is extended for use with switching surges. In order to evaluate insulators under conditions where dry bands would form, it was found necessary to first energize the contaminated insulators with alternating voltage before applying the surges. Included in the investigation are the effect of front time and tail time on the critical flashover voltages, and a comparison of the switching surge performance of five insulator types under various levels of contamination.