Calibration of the Self-Powered Neutron Flux Monitor in a Simulated PWR Lattice

The response of a rhodium all-solid, self-powered incore monitor was measured in a critical assembly mock-up of a typical PWR. The detector signal strength and the power density of adjacent fuel rods were correlated. The detector background, typically 2 to 5%, was highly dependent on the detector environment as well as the incident gamma flux.