Fission chamber detector system for monitoring neutron flux in a nuclear reactor over an extra wide range, with high sensitivity in a hostile environment

摘要

A fission chamber detector system for monitoring neutron flux density in a nuclear reactor includes a preamplifier and signal conditioning unit for amplifying and conditioning neutron signal pulses produced by fission chamber detectors located adjacent the reactor core. The preamplifier and signal conditioning unit are located outside of the containment vessel for the reactor. The amplifier and signal conditioning unit amplify and condition the neutron signal pulses to provide signals that can be transmitted by twisted shielded pairs to a remotely located signal processing unit. The preamplifiers include an input stage that enables the preamplifiers to be controlled remotely to either pass or inhibit neutron signal pulses to an amplifier stage from the fission chambers, and to pass test signals to the amplifier stage.