Temperature distribution on polluted insulator string model

The surface temperature of energized, wetted by steam fog, polluted insulator string model was measured and scanned from the instant of voltage application using an infra-red camera. Visicorder oscillographs were used to trace and record the leakage currents. Results show that the presence of capacitance increases the maximum surface temperature, enhances the degree of non-uniform temperature distribution, helps the formation of dry bands and increases the level and intensity of discharges as well as the probability of the formation of large magnitude leakage current pulses.