Abstract
In measurement of electric conductivity solution, the error due to polarization is often caused. The new method described in this report is of a system of three electrodes and makes an accurate measurement because it is free from the error by polarization. In this method, one additional electrode is combined with the two electrodes of the conventional Kohlransch's Bridge system to eliminate the effect of polarization. Described in detail are its principle, features, temperature compensation method and an example of its application. When an industrial instrument manufactured based on this principle was used at a sewerage treatment station for ten months, good results were obtained.
