Contact contamination and arc interactions

Contact contamination is a major problem for all types of contacts but is more complex for arcing contacts as a result of arc interactions with the contact surface and contaminants. The paper describes arc interactions with mineral particulate and resultant resistances. The complexities of silicone film contamination, migration, and silicon oxide build up are described. The paper also describes the effect of difference automotive loads on silicone reactions. Special arc reactions that occur as a result of silver refractory metal oxidation potential are discussed. For silver contacts, the reasons for high and unstable resistances for DC inductive load applications are discussed. The paper is mainly a review with some added new material.