Determining a Component’s Fault Status and the Status’ Readiness

A diagnosis points at a set of components whose abnormal behavior could explain why a system does not function as intended, and a set of diagnoses points at different such sets of components. It would be an advantage for repair technicians if it, as a complement to the diagnoses, was possible to exactly state which components that certainly are faulty, which that are only suspected to be faulty, and which that are normal, i.e. to state the components’ fault statuses. There would also be an advantage if the technicians could get an indication when a component’s fault status cannot be changed by evaluating additional diagnostic tests, and the fault status is in that case said to be ready. The key contributions in the present paper are conditions that can be used to decide a component’s fault status and the fault status’ readiness. Conditions are stated for both centralized and distributed systems. Copyright c ©2006 IFAC.