A Conductivity Liquid Level Detector for the Nuclear Reactor Environment

An electrical conductivity-sensitive liquid level transducer (LLT) has been developed for and used in the pressurized water reactor (PWR) environment. Local conductivity at each of a vertical stack of electrodes is sampled in continual sequence and the presence or absence of water during each sample interval at each electrode is determined. The LLT was developed for use in test facilities which replicate the PWR environment. Qualification of the LLT for use in commercial nuclear generating stations is not and never was an objective. However, accumulated operating experience with the LLT plus recent improvements in data reduction and in materials processing indicate that an LLT could probably be fabricated and qualified for use in commercial reactors. The transducer and its operating history and performance are described and the data reduction technique and recent improvements explained.