Abstract

A method and apparatus for measuring the concentration of a particular component, e.g. water, in a two-component mixture, e.g. water-oil. A probe having three sets of sensor electrodes is positioned into the mixture. A first elastic sac is secured over the exposed ends of a first set of electrodes and is filled with water. A second elastic sac is secured over the exposed ends of a second set of electrodes and is filled with oil. The ends of the third set of electrodes are left exposed. The electrodes are energized and each generate a signal representative of a measured electrical property, e.g. resistivity, conductivity, or capacitance, of the liquid in which they are immersed. By properly combining these three signals, the concentration of the particular component is determined. Since any changes in temperature and pressure in the mixture being measured with affect the readings from all three sensors equally, the probe is considered self-adjusting and the accuracy of the final measurement is relatively unaffected by these changes.