Circle tests of tracking and erosion of the composite insulator

This paper introduces the change of the characteristics of the surface state and electric performance of the composite insulator samples composed of different material, different process in production, and different colors after 31500 circle tests of tracking and erosion by the wheel test mode. In order to evaluate the change and the comparison of the samples, the test measures the leakage current and its involved characteristic values, hydrophobic state. And we also carry out the impulse power test to the samples after the test. The test appropriately simulates the influence of the weather with shower or with interval between rain and fine under atmospheric contamination on the composite insulator. The two kinds of the producing procedure, shed shaped by injection and vulcanization, and extrusion sheath and then, through the shed in the sheath. The test shows, though both of them has passed the 31500 circle tests, after the time the leakage current occurring and deposit dirtiness were statistic, we can find that the distribution of all the electricity and all dissipation energy passed the surface of the former is uniform, but that´s of the latter is different.