surface tracking can occur on the surfaces of organic insulation or on contaminated surfaces of inorganic insulation. The signs of tracking on organic materials are eroded surfaces with carbon lines. On track resistant organic materials, these erosion patterns will be essentially free of cartbon.
Note that tracking can propagate from either the high voltage or ground terminal. It will not necessarily progress in a regular pattern or by the shortest possible path.
Surface tracking is one of the insulation failure phenomena. It occurs due to electric discharge over the insulation surface because of the dirt, moisture and other contamination accumulated on the insulation surface over a long period of time. This sort of accumulation weakens the creep distance of the insulation surface and small discharge occurs due to the potential gradient between the applied voltage and the ground, and eventually the insulation is damaged and failed.
In addition to surface, the tracking may also occur due to internally in some materials (most probably called internal tracking).
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Surface Tracking
Re: Surface Tracking
