Study or polymeric material characteristics on covered conductors used in Brazil

The use of overhead covered conductors in the Brazilian Distribution System was motivated by an increasing number of faults due to tree contact with bare conductors and trees clearances. As these conductors use covering polymeric insulating materials, there were other problems, such as: tracking and erosion susceptibility, not only due to abrasion (tree contact), but also to the deleterious action of environmental agents (humidity, pollution, UV radiation, etc.), and finally to lower resistance to thermomechanical effects. Many test methods and solutions have been suggested, however, they are not suitable to a tropical climate. Those reasons have lead the CED-Center of Excellence in Distribution of Electric Energy-to investigate cable resistance to our weather conditions, adapting or developing methods that will permit observation and analysis of field characteristics of covered conductors, as well similar accelerated laboratory conditions. This paper presents methodological developments and recommendations for covered conductors´ reception, which is considered an early method for detecting polymer aging signals