Tracking Surface is the propagation of an electrically conductive path along the surface of an electrical insulator due to the breakdown of the insulation material. The tracking test simulates the electrical propagation over the surface under test. It is commonly used to verify the resistance of the insulation materials.
Tracking develops from surface discharge activity associated with the flow of leakage current, especially under wet or contaminated conditions. Arcs created from surface discharges burn the insulating material and create electrically conductive carbonized tracks, reducing or eliminating the insulation properties of the material under test.