Electrical behavior of golden automotive connectors under vibration tests

Connector terminals, particularly in automotive applications can be prone to failure due to small amplitude movements; vibrations have been recognized as one of the main causes of these degradations. The choice of connector design and of materials is often guided by the results of "imposed displacement" sine vibration tests. Here a new experiment has been designed to measure the electrical properties of low level connectors. A four point measurement set-up is used with a dedicated acquisition system allowing high speed measurement of the voltage drop with the possibility to trigger ultra high speed acquisition when a threshold value is reached. Vibration spectra of various types can be imposed to the contact thanks to a dedicated M+P control and acquisition system. Various calibration steps are described both for the electrical measurement and for the vibration response of the system. First results on connectors with a gold finish for automotive applications are described. Their resistance is shown to be very stable for all the vibration spectra tested. Dissymmetric gold tin contacts were used in order to investigate the occurrence of significant electrical resistance variations. The aim of the study is to be able, in the future, to correlate the well known fixed sine amplitude tests to vibration ones closer to real duty conditions of use.