5. Electrical capacitance measurement systems

5.1 Measuring principle

If we connect two conductive electrodes immersed in an insulating medium to a source of alternating current, we create a capacitor whose impedance, at a given frequency, determines the intensity of the current. Any change in capacitance, caused by changes in the level of the products between the electrodes, changes the value of the electric current.

With this measurement principle, if satisfactory results are to be obtained, it is essential to always consider the duality of the parameters electrical conductivity and permittivity (dielectric constant) of the controlled medium.

This is, of course, a true level measurement.