Reference electrodes are used for monitoring cathodic
protection potentials of buried or immersed metallic structures [1-6].
In the market, many types of reference electro- des are available for this purpose, such as saturated calo- mel, silver/silver chloride and copper/copper sulfate. The latter is the most used for buried pipelines and consists of a copper rod immersed in a saturated copper sulfate aqueous solution both involved by a polymeric cylindrical body.
These electrodes contain a porous ceramic junction plate located at the cylindrical body bottom to permit ionic flux between the internal electrolyte of the reference electrode(copper sulfate) and the external electrolyte (generally soil).