Arc tracking is a progressive electrical failure mechanism which leads to creation of a carbonized path along the surface of a non-conducting insulator that connects two electrical conductors. Arc tracking is significantly enhanced by high voltage and conductive contaminants, such as moisture, on the surface. Once a carbonized path is created, current flow, including arcing, may then occur along this path.
Many electrical fire ignitions have been attributed to arcing across a carbonized path. If an electrical system is incapable of detecting errant electrical current, a carbonized path may propagate for days, weeks or even years.
A current-carrying and arcing carbonized path can then cause a combustible host substrate to smolder and potentially transition to an open flame. WHA has performed numerous investigations of arcing-through-char cases associated with arc tracking, including tracking on printed circuit boards (PCB).WHA has discovered that certain materials in the PCB can become conductive when exposed to elevated temperatures and allow a track to propagate. WHA's engineers are qualified to work with you on evaluating this electrical failure mechanism in your system of interest.