SU873093A1 - Device for measuring liquid media electric conductivity - Google Patents

Description

(54) DEVICE FOR ELECTRICAL CONDUCTIVITY MEASUREMENT

LIQUID MEDIUM

The invention relates to devices designed to measure the electrical conductivity of liquid media, and can be used to control the foaming of latex mixtures in the production of foam rubber, the degree of products, the solids concentration of solutions in the petrochemical, chemical, mining and other industries. Devices are known for measuring the RF electrical conductivity of liquid products, comprising a stabilized power source, a generator, a power amplifier, a measuring bridge circuit, two capacitive measuring cells, rectifying devices, and a secondary device DD. The closest to the present invention is a device for measuring the electrical conductivity of liquid media containing a stabilized writing source, a secondary device, an alternating voltage generator connected through a power amplifier to a measuring circuit including a primary converter, a rectifier, a thermal compensator with a temperature-sensitive element G2. The disadvantages of these devices are the non-linearity of the code signal from changes in the electrical conductivity of the controlled medium, which leads to a decrease in the metrological characteristics of the devices (accuracy, stability, etc.). The purpose of the invention is to increase the measurement accuracy by obtaining a linear output signal. To achieve this goal in a device for measuring the electrical conductivity of liquid media containing a stabilized power source, a secondary device, an alternating voltage generator, connected through a power amplifier to the measuring circuit, switch on and the primary converter, rectifier, thermal compensator

with a temperature-sensitive element, a reference resistor is inserted in the circuit connected in series with the primary converter and forming a voltage divider with it, while the common point of the reference resistor and primary converter is connected via a rectifier to one of the thermal compensator inputs.

The drawing shows a schematic diagram of the proposed device. The device contains a stabilized power supply 1, an alternating voltage generator, a power amplifier 3, from the layout circuit 4, which includes a reference resistor 5, a primary converter 6 with a temperature-sensitive element 7 combined with it, a rectifier 8, a thermal compensator 9, a reference source 10 voltage and secondary device 11.

The device works as follows.

The alternating voltage from the source 1 of the reference voltage, the generator 2 through the power amplifier 3 is fed to the reference resistor 5 and the primary converter 6, and the reference resistor 5 forms with the primary converter 6 a voltage divider with a ratio of at least 4: 1 in the dynamic mode at the minimum electrical conductivity of the controlled medium. Next, from the primary converter 6, a signal proportional to the conductivity of the controlled medium through the rectifier 8 is fed to one of the inputs of the thermal compensator 9, which, together with the temperature-sensitive element 7, performs temperature correction when the temperature of the controlled medium changes, and to the other input of the thermal compensator 9 a signal is received from the source the reference voltage 10 to install an electrical device. A stercompensator will remove the secondary instrument II.

The proposed device makes it possible to reduce the consumption of raw materials, for example, natural latex, in the production of foam rubber at rubber plants and to improve the quality of finished products.

Claims (2)

Invention Formula A device for measuring the electrical conductivity of liquid media containing a stabilized power source, a secondary device, an alternating voltage generator connected through a power amplifier to a measuring circuit including a primary converter, a rectifier, a thermal compensator with a temperature-sensitive element, different from that in order to improve measurement accuracy , a reference resistor connected in series with the primary converter and forming a voltage divider with it is inserted into the circuit, with the common point the reference resistor and the primary converter are connected via a rectifier to one of the thermal compensator inputs. Sources of information taken into account in the examination I. USSR Copyright Certificate No. 292107, cl. G 01 N 27/02, 1969. 2. USSR author's certificate No. 575928, cl. G 01 N 27/02, 1975 (prototype).