MULTIPLE-ELEMENT TYPE NEUTRON DETECTOR

摘要

PURPOSE:To enhance operating efficiency of a reactor by improving reliability for monitoring the reactor and then relaxing the restriction im terms of operation of the reactor due to the limitation in the number of allowable bypasses and then reinforce monitoring by achieving the abnormality diagnosis function of a neutron detection element. CONSTITUTION:A plurality of neutron detection positions are set at different positions in axial direction within a protection tube 12 and then a plurality of neutron detection elements 14 are incorporated and multiplexed, which can be applied to a local output detector. Also, the neutron detection positions can also be applied to a detector for starting and that for increasing output. A neutron detection element is in ionization box format with a column-shaped anode 16 and a cylindrical cathode 18 surrounding it and a plurality of neutron detection elements are laid out vertically in one piece or they may be laid out in parallel in one piece. By comparing the signals of the multiplexed neutron detection elements, abnormality diagnosis can be made.