LMFBR Neutron Monitoring Systems - A Review of the State-of-the-Art

The French PHENIX, the British PFR and the West German SNR-300 Prototype Fast Reactor neutron monitoring system concepts are reviewed and compared to U. S. systems. Emphasis is placed on the type of neutron detectors and preamplifier electronics being used. The French Series CFUC and the British Type P7 high temperature (~1050°F) fission counters are described and indicated performance discussed based upon published results. High temperature compensated ionization chambers manufactured in Europe and the U. S. are briefly covered. The European low level flux monitoring preamplifier philosophies are related and compared to present and planned U. S. systems. Major differences are noted and discussed. Recent test results from wide range systems mated with fission counters operating at 725°F in the EBR-II Nuclear Instrument Test Facility (NITF) are presented. The NITF facility is briefly described.