Electrical activities associated with inclined-plane tracking and erosion test

A leakage current monitoring system was installed to measure the electrical activities including peak leakage current, average leakage current, cumulative charge, and number of leakage current pulses in four ranges: 1-5 mA, 5-15 mA, 15-50 mA and 50-200 mA during the inclined-plane test (ASTM D2303). The electrical activities were measured for two materials-a silicone without aluminum trihydrate (ATH) and an ethylene vinyl acetate copolymer (EVA) using the step voltage procedure. The results illustrated the intensity of the electrical activities associated with the applied voltages and the flow rates of the contaminant solution for the two polymers. The severity of the test was quantitatively defined by the detailed measurements of electrical activities. It was also demonstrated that even with intensive arcing, excellent tracking and erosion resistance can be achieved with both polymers. The additives and fillers are more important than the generic polymer types in achieving tracking and erosion resistance for polymer compounds