Composite insulator diagnostics in service and condition monitoring in very Harsh coastal environment of Iran

During the last decades the use of composite insulators has grown all over the world. And also diagnostic techniques for these insulators have been studied and developed. According to DIN50019, the coastal districts of Persian Gulf are classified as extreme hydrothermal climatic zone. Unusually high saturation vapor pressure up to 53mbar observed in this zone, justify this marking, as such air humidity phenomena are unique in the free atmosphere of the earth and are absolute extremes. Intensive night falls of dew, which can occur regularly for several months, long periods of rainless and sultry weather and high level of marine pollution worsening the situation for power lines. This paper present an applicable program for diagnostics and condition monitoring (CM) of 20 kV distribution line which is located in a coastal district which pollution level of this region is classified at very heavy category as shown in figure1.with pilot project in this area, this model of CM presented the best tool for Evaluation of reminded life of all kind of insulators.