Silicone Coating of Insulators: Latest Technical Knowledge Based on Field Performance & Laboratory Testing by Jean-Marie George

Substituting polymer insulators with a hydrophobic surface over glass has substantially impacted selection of insulators for polluted environments as well as for certain HVDC applications. Today many suppliers offer glass or porcelain insulators with coatings applied either in the factory or on site. This presentation will explain the key requirement of coating adherence. It will also review a unique field experience that brings light to the possible performance limits of coated insulators under extreme service conditions that go far beyond the pollution classifications within IEC TS60815.