FIELD: measuring equipment.
SUBSTANCE: invention relates to measuring equipment and can be used for high-precision determination of the position of the interfaces between the components of a three-component medium located in a certain container, one component above the other, and forming flat interfaces, in particular, air and two immiscible liquids with different densities. The substance of the claimed solution consists in the fact that the apparatus for measuring the position of the interfaces between the components of a three-component medium in a container, one component above the other, forming flat horizontal interfaces, comprises two vertically placed segments of a long coaxial line, filled with the components of the medium in accordance with the location thereof in the container, lines of communication of said segments of a long coaxial line with the corresponding electronic units for excitation of electromagnetic oscillations in the first and second segments of a long line at the resonant frequency thereof ƒ1 and ƒ2, respectively, and implementation of measurement of ƒ1 and ƒ2, the outputs whereof are connected to the inputs of a functional converter, connected to the output whereof is a recorder wherein the results of the conversion of ƒ1 and ƒ2 are recorded, based on the results whereof the position of each interface is determined, the first and second segments of a long line are made with a uniform distribution of energy of the electric field along said segments, but in each, at least one of the conductors is covered with a dielectric shell along the entire length, characterised by the fact that the segments of a long coaxial line are located coaxially and formed by a combination of two coaxial metallic cylinders and a central conductor coaxial therewith, wherein the inner surface of the inner cylinder acts as an outer conductor of one of the segments of a long coaxial line, another conductor whereof is the central conductor covered with a dielectric shell along the entire length, and the outer surface of the inner cylinder, covered with a dielectric shell along the entire length, acts as the inner conductor for the other segment of a coaxial long line, wherein, in the first and second segments of a long coaxial line, the quantity 
has a different value, wherein εp is the relative permeability of the material of the shell, a1, r, and a2 are the diameters of the inner conductor, the shell, and the outer conductor of each coaxial segment of a long line, respectively.
EFFECT: increase in the accuracy of measurement.
1 cl, 2 dwg
