Measurement of a physical magnitude in a conducting environment without previous knowledge of the environments conductivity, involves using two out of phase polarized electrodes with probe between them

摘要

Measuring system consists of at least two electrodes (N, P), an electrically conducting medium, and electrical supply (4, 14N, 14P) which applies periodic voltage between electrodes. Measuring probe (2) is immersed in the medium in proximity to the electrodes for measuring the signal in the medium. Electrodes are fed with two out of phase polarizing signals between the phase and phase opposition. A unit (5) measures the effective value of the measuring signal with respect to one of the electrodes (N). A unit (16) measures the out of phase measuring signal relative to the signal at one of the electrodes (N) taken as reference. The electrodes (N, P) are plane and parallel to each other. The probe (2) is between the electrodes. An Independent claim is also included for the use of three electrode pairs.