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Summary
DescriptionTracking1.jpg
English: A polycarbonate plate, originally part of a high voltage Trigatronspark gap switch, tracked by a 2D Electrical tree. The device had a design flaw: the small white cylinder of PVC began to break down when subjected to corona discharge. This liberated hydrogen chloride HCl gas. The HCl then absorbed water from the air, depositing a partially-conducting film of hydrochloric acid on the surface of the polycarbonate. This led the formation of 2D carbonized tree-like patterns across the surface of the polycarbonate. The conductive paths ultimately led to premature breakdown and operational failure of the trigatron. From Bert Hickman, Stoneridge Engineering, http://www.capturedlightning.com
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Polycarbonate plate from a Trigatron tracked by a 2D Electrical Tree. In this case, a small piece of PVC began to track, causing a film of HCl to be deposited on the plate. The partially conducting film led to rapid tracking across the sur