exida Recorded Webinars

Failure rate data for many different devices has shown that a device failure rate changes during the operating time interval. The failure rate would follow what has become known as the “Bathtub Curve.” Failure rates can be approximated as a constant value during the flat bottom of the Bathtub Curve for a time period known as Useful Life. At some point in time, the failure rate increases, often rapidly. This marks the end of the Useful Life time period. In Functional Safety (FuSa), one critical performance metric, called PFDavg (the average probability that a safety protection function will not work when needed) is calculated. Failure rates are an input to this calculation and are only valid during the Useful Life. Therefore, Useful Life is required for FuSa. An FMEDA can be used to predict this important metric. This webinar explains the Reliability Engineering background and the method used in FMEDA.