On-line testing of PARR instrumentation by plant computer

This report describes the utilization of PARR plant computer for automatic periodic testing of nuclear instrumentation in the acquisition and processing of nuclear channel signals. Based on statistical analysis the performance characteristics like mean value, standard deviation and probability distributions of nuclear channel signals are obtained in real time. The computed errors of the channel output are compared with the standard nuclear detection errors and the computer generates a message in case the error exceeds the maximum permissible error by a fixed margin. In this way the faulty channel is automatically identified at an earlier stage, which facilitates instrument maintenance scheduling. The on-line testing program is particularly advantageous for the performance evaluation of those channels whose output signal is either not recorded on the console or which are used to generate reactor trips alone. (author)