Load Limits of Ultra Miniature Electromechanical Signal Relays

摘要

Modern telecom and signal relays have been optimized to carry and switch low signals and to withstand high dielectric strength. Recent designs have extremely small physical dimensions and are comparatively cheap. Small size and low cost also make this type of relay very attractive for industrial and automotive applications. For industrial and automotive applications performance characteristics other than low and stable contact resistance values are of importance. While, for industrial applications, safety aspects and inductive load switching characteristics are of major importance, in automotive applications, high switching currents, inductive and lamp loads and high ambient temperatures are essential. Tests were carried out in order to determine the limitations of small size relays. The results obtained clearly show the unexpectedly high load range which signal relays are able to cover. Despite their small size, these relays can handle switching loads up to several hundred volts and currents up to 5 A. On top of the high switching current there is high excess current capability, and relays can work at extreme ambient temperatures between -55 and more than +105 degrees C.