In the non-submerged diaphragm types the invasion of the anodic compartment by caustic is much reduced and the efficiency and life increased.

The new UC sensor uses a technology called anodic stripping voltammetry that incorporates three electrodes: a working electrode, a reference electrode and an auxiliary electrode.

The impurities accompanying the synthetic tannin, i.e., salts, free sulphuric acid, and some phenols, migrated anodic and cathodic respectively, according to their charges.