Wide Range Neutron Monitor

The Wide Range Neutron Monitor (WRNM) is a newly developed neutron monitoring channel which was initially conceived as a means to meet Regulatory Guide 1.97 requirements for post-accident neutron monitoring. The scope was expanded to include the startup monitoring function with the aim of replacing both the source and intermediate range monitors in boiling water reactors. The WRNM, consisting of a newly designed fixed incore regenerative sensor and new electronics, which include both counting and MSV channels has been tested in several reactors and its capabilities have been confirmed. The channel will cover the neutron flux range from 103 nv to 1.5×1013 nv; it has greater than 1 decade overlap between the counting and mean square voltage channels. Because of the regenerative fissile coating the sensor, even though fixed incore, has a life of approximately 6.0 full power years in a 51 kW/liter BWR.