The influence of the vibration test mode on the failure rate of electrical connectors

A new model for the reliability prediction was developed and validated in previous investigations in order to enable the determination of the failure in time (FIT) of electrical connectors from highly accelerated life tests (HALT). The established testing method considers the influence of temperature, thermal cycling and vibration on the failure rates of electrical connectors. Various stress levels, i.e. the combinations of different test parameters, were derived from the ZVEI Technical Guideline TLF 0214 for low voltage automotive connectors. The applied vibrational load was initially defined as a sinusoidal test mode. The aim of this study is to investigate the influence of the vibration test mode on the failure rates. Two commonly used automotive connectors are chosen and subjected to stresses in HALT under two different types of vibrational load. The sinusoidal test mode along with the random vibration test mode are taken into account. The influence of the vibration test modes is subsequently determined by comparing the numbers of failures. Additionally, the principles of determining the coefficient of vibration are discussed and the specific coefficients for the chosen connectors are calculated based on the test results. A guideline, derived from this investigation, to select an appropriate vibration mode and vibration level is provided in order to compare the reliability of different electrical connectors.