Fission Chambers for Out-of-Core Use

Fission Chambers for Out-of-Core Use

PHOTONIS manufactures a wide range of fission chambers for out-of-core use in severe environmental conditions, and are used in thermal neutron detection for up to 11 decades for wide range reactor monitoring, and waste monitoring. The well-insulated construction of a PHOTONIS detector will ensure the continual operation of the unit.

Gas filled neutron detectors are designed to operate in three modes.  Pulse mode analyzes and counts individual detector pulses.  Fluctuation, or Campbell mode, is used to analyze the fluctuation of the direct current from the detector.  Current mode is used to measure the mean of the direct current from the detector.

A complete Inconel detector protection can be requested. This protection is LOCA (loss of coolant accident) and post LOCA qualified.  These fission chambers are typically designed with a maximum operating temperature of 250°C (although some versions can monitor up to 600°C and up to 20 bar external pressure) and are equipped with an integrated HN connector.

Due to the extreme operating conditions of fission chambers, PHOTONIS also recommends the use of an insulated cable designed specifically for the detector.


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