Relevancy in fault detection analysis

The author discusses the concept of relevancy of circuits, parts, and part failure to system performance and the impact of relevancy to fault detection analysis results. Relevancy requires that all circuits, parts, and part failure modes in a system be analyzed to determine if, in the event of an equipment malfunction, there is an adverse effect on system performance. Thus, a circuit failure critical to system performance is relevant, whereas a failure not critical to system performance is nonrelevant and therefore does not affect equipment operation. By excluding nonrelevant circuits, parts, and part failure modes form the fault detection analysis, the results of the fault detection predictions for a system´s built-in test (BIT) design and/or fault detection test software are more accurate