METHOD FOR DETERMINING LEVEL OF DIELECTRIC SUBSTANCE Russian patent published in 2013 - IPC G01F23/26 

FIELD: measurement equipment.

SUBSTANCE: sine voltage is shaped on a capacitance level sensor; complex current is measured through a dry capacitance level sensor and complex current is measured through the capacitance level sensor being filled. The first equivalent circuit of the capacitance level sensor is set, which consists of parallel connected electric capacity and active resistance, formation of sine voltage on the capacitance level sensor is performed at two frequencies; after that, series measurement of complex current through dry level sensor and a reference on each of two frequencies is performed; at that, measurement results are fixed; electric capacity of the dry level sensor is determined and fixed; increment of electric capacity of the capacitance level sensor is calculated and fixed at its full submersion in dielectric substance. Relative filling of capacitance level sensor with dielectric substance is determined as difference of values of electric capacity of the capacitance level sensor being filled and electric capacity of dry capacitance level sensor, which is referred to increment of electric capacity of the capacitance level sensor fully submerged into dielectric substance. The second equivalent circuit of capacitance level sensor is set, which consists of in-series connected electric capacity and active resistance, and as per complex currents measured and fixed before through the capacitive level sensor and the reference on each of two specified frequencies there determined and fixed is in-series connected electric resistance of chains of the level sensor, as per which reliability of determination of dielectric substance level is evaluated.

EFFECT: excluding measurement results of the level, which occur as a result of failure in a long communication line between a sensor and measuring equipment.

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