Climatic ageing tests on polymeric power cable terminations

During outdoor service, power cable terminations must withstand the combined effects of sunlight, contamination and moisture in addition to thermal cycles and periodic overvoltage surges. CEPEL has constructed a weathering test laboratory to simulate these conditions. After briefly describing the test chamber and testing schedule, this paper summarizes data and observations made during tests for one year on prototype ethylene propylene rubber terminations for 12/20 kV cables. The EPR terminations suffered negligible degradation during 40 weeks at 13 kV (11 V/mm) while subjected to UV irradiation (max. dose 14 kWh/m/sup 2/) and salt spray for a total of 570 hours. Heat cycling to 60 degrees C tends to reduce surface discharges during salt-fog cycles compared with operation at ambient temperature.<
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