Multi-channel standard gas flow control device for calibrating mining gas sensor

Abstract

The invention relates to a multi-channel standard gas flow control device for mining gas sensor verification. The multi-channel standard gas flow control device comprises a main controller, a plurality of single-channel gas mass flow controllers and an adapter circuit arranged on an adapter plate, the main controller comprises a main control MCU, and an AD conversion unit, a DA conversion unit, aman-machine conversation unit, a communication circuit and a power supply circuit which are connected with the main control MCU. A hardware PID control circuit is adopted in the gas mass flow controller to control gas flow, and meanwhile, analog voltage in direct proportion to the gas flow is output; the AD conversion unit collects a voltage signal which is output by the single-path mass flow controller and is in direct proportion to the flow of the single-path mass flow controller through the switching circuit; the DA conversion unit outputs a control analog voltage through the switching circuit to control the flow of each single-path gas mass flow controller; and the main control MCU controls the AD conversion unit and the DA conversion unit to realize flow data acquisition and control voltage output. According to the invention, the purpose of improving the verification work efficiency can be achieved.

Description

technical field [0001] The invention relates to a gas flow control device, in particular to a high-precision multi-channel standard gas flow control device used for mine gas sensor verification equipment. Background technique [0002] A variety of equipment for detecting gas concentration and flow is used in coal mine production. According to relevant regulations, these equipment need to be checked regularly, and the calibration equipment needs to provide high-precision gas concentration and flow. Gas sensors used in coal mine production mainly include CH 4 , CO, H 2 S, O 2 During the use of these sensors, due to the inherent characteristics of the catalytic element, problems such as zero point drift and span drift will inevitably occur, resulting in the inability to accurately reflect the concentration of the gas to be tested, so it must be tested regularly. During the detection process, different concentrations of standard gas concentrations must be provided, and the st...

AI Technical Summary

Problems solved by technology

[0003] At present, most of the mining gas sensor verification equipment adopts analog flow controllers, which require the inspectors to manually set and adjust the flow controllers, which is cumbersome and inefficient. low efficiency

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