EPRI Core Protection NANTeL Practice Test

When multiple protection channels monitor the same condition, a degradation in one channel but healthy performance in the others means you have a single-channel fault rather than a system-wide failure. The right approach is to treat it as a degraded channel issue: perform targeted testing to confirm the fault, isolate the degraded channel if needed to prevent it from influencing trip logic, rely on the remaining healthy channels to make trip decisions, and schedule repair to restore full protection. This preserves system reliability by using redundancy for protection while containing the fault and returning the system to full capability. Ignoring the degraded channel risks missed or false trips once the fault propagates; tripping the entire system is unnecessarily intrusive for a single degraded channel; replacing all channels is overly drastic when only one is at fault.