Assessment Of Containment Fan Cooler Degradation By Motor Current Signature Analysis

Abstract

Nuclear plants develop a surveillance and maintenance program that relates to assuring the continuing adequacy of important plant equipment. This is especially true regarding nuclear safety-related equipment which is considered to be part of the "Safety-Related structures, systems, or components that are relied upon to remain functional during and following design basis events to ensure the integrity of the reactor coolant pressure boundary, the capability to shut down the reactor and maintain it in a safe shutdown, and the capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposure comparable to lOCFR part 100 guidelines" consistent with 10CFR50.65(1). In addition electrical nuclear safety related equipment which may be subject to a harsh environment must be maintained in a state of readiness to perform during the harsh environmental conditions of the nuclear accident. A cost- effective surveillance and maintenance program should assure that equipment adequacy to perform or remain operable is retained. This paper describes the criteria used for selection of a Non-Intrusive Condition Evaluation (NICE) system by Motor Current Signature Analysis (MCSA) to assess selected conditions of relatively inaccessible incontainment motors during normal operation. It also describes the successful results from use of such a system.