Monitoring equipment environment during nuclear plant operation at Salem and Hope Creek generating stations

Monitoring of environmental parameters has become a significant issue for operating nuclear power plants. While the long-term benefits of plant life extension programs are being pursued with comprehensive environmental monitoring programs, the potential effect of local hot spots at various plant locations needs to be evaluated for its effect on equipment degradation and shortening of equipment qualified life. A significant benefit can be experienced from temperature monitoring when a margin exists between the design versus actual operating temperature. This margin can be translated into longer equipment qualified life and significant reduction in maintenance activities. At PSE and G, the immediate need for monitoring environmental parameters is being accomplished via the use of a Logic Beach Bitlogger. The Bitlogger is a portable data loggings system consisting of a system base, input modules and a communication software package. Thermocouples are installed on selected electrical equipment and cables are run from the thermocouples to the input module of the Bitlogger. Temperature readings are taken at selected intervals, stored in memory, and downloaded periodically to a PC software program, i.e., Lotus. The data is formatted into tabular or graphical documents. Because of their versatility, Bitloggers are being used differently at the authors Nuclear facility. At the Salem Station (2 Units-4 loop Westinghouse PWR), a battery powered, fully portable, calibrated Bitlogger is located in an accessible area inside Containment where it monitors the temperature of various electrical equipment within the Pressurizer Enclosure. It is planned that close monitoring of the local hot spot temperatures in this area will allow them to adjust and reconcile the environmental qualification of the equipment