SU1350585A1 - Device for non-contact measurement of liquid electric conduction - Google Patents

Abstract

The invention relates to the field of analytical instrumentation. The purpose of improving the accuracy of measurements. The device for the contactless measurement of the electrical conductivity of a liquid contains a measuring generator, a recorder and a transformer conductivity sensor with a liquid turn connection, a measuring winding connected to a symmetrical output of the measuring generator. A functional generator, a comparator, a pulse counter and a frequency divider, the input of which is connected to the unbalanced output of the measuring generator, are additionally introduced into the device, and the output is connected to the reset input of the pulse counter. The function generator is connected to the windings of the magnetizations. The pulse counter, to the output of which the recorder is connected, is connected via a comparator to the measuring winding. 1 il. (L 00 JV about ate 00 ate

Description

ten

15

1350585

The invention belongs to the field of analytical instrumentation and can be used to solve a wide class of problems of measuring parameters of liquid media, for example, during hydrological studies;

The aim of the invention is to increase the measurement accuracy.

The drawing shows a functional diagram of the device.

The device for the contactless measurement of the electrical conductivity of a fluid includes a measuring generator 1, a transformer sensor 2 of electrical conductivity with primary winding 3, a solid connection 4, a biasing winding 5 and a measuring winding 6e functional generator 7, a comparator 8, a pulse counter 9, a recorder 10 and a frequency divider 11. Functional generator 11 is connected to the bias winding 5, Pulse counter 9 is connected to measuring winding 6 via a comparator 8, Record 10 is connected to the output of counter 9, Unbalanced output of measuring generator 1 is connected to the reset input of counter 9 through a divider 11 The symmetric output of the measuring generator 1 is connected to the primary winding 3 of the transformer sensor 2. The device operates as follows.

The measuring generator 1 supplies to the transformer sensor 2 a periodic voltage with a frequency fp. A winding

/

W In D

A U, f

(-) 2 (N-O,

b where x 20

electrical conductivity of the fluid;

A - conductive constant of the sensor; - frequency of bias current; If is the bias current amplitude; W is the number of turns of the bias winding;

fg is the frequency of the supply voltage; and voltage amplitude at generator output 7; N is the number of pulses counted

counter 9 for one measurement. The number of zero values is fed to counter 9, where they are counted during a time T, equal to

m

K f.

Where k is k: coefficient of frequency division of block 11;

measuring generator frequency

The counting results are presented at 10,

Improving the measurement accuracy is achieved by directly converting the measured value into the pulse code 35 and eliminating the amplitude errors of the analog conversion.

40

Claims (1)

Invention Formula A device for the contactless measurement of the electrical conductivity of a fluid, containing a measuring generator, a recorder and a transformer sensor measuring winding 6, One- 45 electrical conductivities with a liquid current F, which induces a current in the liquid coil 4 connection. Current value Depends on the magnitude of the fluid's electrical conductivity The current of the link 4 excites the magnetic flux F, excites F, the additional magnetic flux F is excited in the magnetic circuit, Thus, the bias winding 5 fed by the current function generator 7, Thus, the EMF of the measuring winding 6 will be to be determined by the superposition of magnetic fluxes f + Fz. Comparator 8 extracts the function of the signal beats, i.e. the number of zero values of the total emf function. This informative feature is associated with the electrical conductivity of the fluid with the following relation: 50 connection loop, measuring winding, bias winding and primary winding connected to the symmetric output of the measuring generator, characterized in that, in order to improve the measurement accuracy, it introduced a functional generator, comparator, pulse counter and frequency divider, whose input g is connected to the unbalanced output of the measuring generator, and the output is connected to the reset input of the pulse counter, the function generator is connected to the winding under / W In D A U, f (-) 2 (N-O, 0 five 25 so b where x 0 electrical conductivity of the fluid; A - conductive constant of the sensor; - frequency of bias current; If is the bias current amplitude; W is the number of turns of the bias winding; fg is the frequency of the supply voltage; and voltage amplitude at generator output 7; N is the number of pulses counted counter 9 for one measurement. The number of zero values is applied to counter 9, where they are counted in a time T equal to m K f. Where k is k: coefficient of frequency division of block 11; measuring generator frequency The counting results are presented at 10, An increase in the measurement accuracy is achieved by directly converting the measured value into a pulse code and eliminating the amplitude errors of the analog conversion. 0 connection, measuring winding, bias winding and primary winding connected to the symmetric output of the measuring generator, characterized in that, in order to improve the measurement accuracy, it introduced a functional generator, comparator, pulse counter and frequency divider whose input g is connected to asymmetrical output of the measuring generator, and the output is connected to the reset input of the pulse counter, the function generator is connected to the winding of which the output voltage is connected to the register bmotkoy.