Automatic scanner loggers for small installations

Automatic scanner loggers convert analogue signals representing process variables to more concisely recorded digital data, and in many instances have replaced conventional recorders and indicators previously in use in centralized control rooms. To justify the use of a scanner logger on a small installation is fairly difficult since conventional multipoint recorders will normally meet the requirements at a greatly reduced cost. There is a need for a range of digital instruments to replace the conventional potentiometric recorders eliminating the disadvantages of these instruments while providing relevant information. This paper discusses such a range of instruments referring particularly to their advantages over conventional potent ionietric recorders.