Properties of Short Arc Phenomena on AgCu Electrical Contact Pairs for Automotive Electronics Devices

Characteristics of arcs occurring between electrical contacts affect the reliability and lifetime of automotive electronic devices. Accordingly, it is important to investigate the properties of arcs on AgCu contact material. In this paper, arc phenomena occurring between AgCu electrical contact pairs in a DC 14V lamp switch circuit are observed with high-speed camera (12,000frames/s). The arc voltage and current are measured, simultaneously. The photographs taken with the high-speed camera were correlated to the changes in the arc voltage, current and calculated arc energy. The observed arc emitting time is less than 30mus. The irradiating arc power increased as the current at the lamp switch circuit increased. More energy on making arcs is discharged than the energy on breaking arcs. When the contacts were slowly closed, multiple arcs were emitted without rebounding. Moreover, after the single pip reached certain height the arc energy was so concentrated that the pip was burst. It appears that the position of contact for these electrical contact pairs moved when multiple short arcs were blew out as the contact slowly moving operation.