Noise Analysis System Data Aquisition Block Diagram

W.H. Technologies has manufactured for OPG’s Inspection & Maintenance Services, data acquisition systems that allows monitoring of the safety shutdown systems and the reactor regulating system during the start of an outage. The unit is typically brought to 60% Full Power and the SDS system is manually tripped by the operator. The data is later analyzed using a reactor model and degraded detectors are identified. Since these systems are connecting to the plant safety system certain design criteria had to be met, such as isolation and current leakage. Also MTBF analysis had to be calculated to show the reliability of the system was not being compromised.

The permanently installed In-Core Flux Detectors (ICFD) are part of safety shutdown systems in nuclear reactors. They are designed to detect a sudden increase in neutron flux caused by an accident, and must therefore quickly respond to flux increases within a specified time interval in order to meet safety requirements. The dynamic response of an ICFD can change over time due to burn-up of material and as result of defects. In order for the ICFD’s respond quickly enough to meet safety requirements, their prompt response component must be above the minimum allowable limit and must be tested periodically. This testing can be performed by evaluating dynamic response of ICFD’s to a sudden power change in the reactor, which is the shorter than the time constant for the fastest delayed component.