Conductivity cell for water-based solutions

摘要

A cell (M) for contact-free measurement of the specific conductivity of water-based solutions uses two coupled electrodes (E) of single alternating current capacity. Each electrode consists of a dielectric capacitor ceramic foil (1), a metallising layer (2) and a ceramic-foil bearer (3) which carries through the contact signal and provides mechanical stability to the electrode. The coupled electrodes are arranged in the cell so that the capacity of the electrolyte is small. A current (Ug) of 3 volts with a frequency of 20 kHz is applied and the voltage fall-off (Um) evaluated by a resistor (Rm), from which the conductivity of the solution can be determined.