On-Line Monitoring Of Sensors

The article considers the short results of the fulfilled research and implemented requirements in the field of on-line monitoring of sensors (OLM) at the Ukrainian nuclear power plants (NPP). OLM is a system of planned (periodic) monitoring of the technical characteristics of sensors at the installation location (without their dismantling) during the launch, shutdown, and operation of the NPP power unit. During OLM within the surveillance system an assessment, monitoring, and control of the condition of the sensor is performed depending on the influence of certain factors. The results of OLM are used to justify decisions regarding the further calibration of sensors.The main requirements of industrial standard SOU NAEK 234:2021 "Engineering, scientific and technical support. Requirements for procedures for monitoring the condition of pressure sensors at NPPs" developed by specialists of the State Scientific and Technical Center for Nuclear and Radiation Safety (Ukraine) are described in the article. Namely, the purpose and tasks of OLM, the conditions for conducting OLM, and the main stages of OLM for the stationary mode of operation of the NPP power unit and OLM after the launch or shutdown of the NPP power unit are considered. An example of OLM analysis results and the advantages of using of OLM are also presented.