Headspace sampler control system and control method thereof

Abstract

A headspace sampler control system and a control method thereof belong to the field of gas phase chromatographic sample pre-treatment device control technology. The headspace sampler control system comprises a programmable controller, a temperature module, an analog quantity input and output module and man-machine interaction equipment. The programmable controller is connected with the temperature module and the man-machine interaction equipment. The temperature module is connected with the analog quantity input and output module. The programmable controller, the temperature module and the analog quantity input and output module are respectively connected with related components of a headspace sampler. The headspace sampler control system has advantages of high stability, high interference resistance, easy operation, easy maintenance, no requirement for welding of a main circuit board, convenient wiring and easy function expansion. Through a self-checking process for each key component of the headspace sampler, problem finding can be realized and a fault point can be found out directly. High control precision and simple operation are realized in a process for controlling temperature and pressure of a heating chamber, a valve and an air path. One-key sample incoming can be realized in an automatic control process for sample incoming of the headspace sampler. Operation time of an operator can be effectively reduced.

Description

technical field [0001] The invention belongs to the technical field of control of a gas chromatography sample pretreatment device, and in particular relates to a headspace sampler control system and a control method. technical background [0002] Headspace sampler is a convenient and fast sample pretreatment method in gas chromatography. Its principle is to put the sample to be tested in a closed container, and heat up the temperature to make the volatile components volatilize from the sample matrix. When the equilibrium is reached in the gas-liquid (or gas-solid) two-phase, the top gas is directly extracted for chromatographic analysis, so as to test the composition and content of the volatile components in the sample. The use of headspace sampling technology can avoid the tedious and cumbersome sample pretreatment process, avoid the interference caused by organic solvents to the analysis, and reduce the pollution of the chromatographic column and the injection port. [00...

AI Technical Summary

Problems solved by technology

[0003] Headspace sampler control includes sample heating, gas path heating, positioning injection needle control and other parts. At present, the control system of headspace sampler mostly uses single-chip microcomputer (single-chip microcomputer) technology. The disadvantage of this technology is that the main control The board is affected by factors such as plate-making process, layout structure, device quality, etc., which leads to the poor anti-interference ability of the control system of the headspace sampler developed by the single-chip microcomputer, high failure rate, difficult expansion, and strong dependence on the environment

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