CO检测电路.doc

摘 要 一氧化碳气体浓度的高低是化工、煤矿及家庭是否发生自然灾害的重要标志之一，也是导致人员中毒死亡的重要因素。 因此，在化工、煤矿的监控系统中增设对一氧化碳检测的系统十分必要，而且很普遍。普通的一氧化碳浓度检测器检测到一氧化碳浓度超标时，电压比较器输出的脉冲信号发生突变，触发报警器报警，但是技术人员无法掌握一氧化碳浓度值和气体泄漏的位置。随着现代信息技术的飞速发展和传统工业改造的逐步实现，能够独立工作的气体浓度检测和显示报警系统的需求量越来越大。 本文设计了一个可进行巡回检测气体浓度的电路，其中包含直流稳压供电电路、浓度信号检测及变换电路、开关控制电路、模/数转换电路、数字显示电路和超限报警电路六个部分。可实现检测路数及检测浓度同步显示等功能。 该系统的工作原理为：直流稳压电源为整个电路供电，传感器将体积浓度转换成电压信号，经过线性化等一系列处理后，通过模拟开关送到模/数转换器中，最后通过数字显示电路显示出检测路数和气体浓度值。如果浓度超过限定值，报警器就会报警。这种电路具有实用性强、可靠性高、测量精度高等特点，可广泛应用于工业、医疗卫生、环境监测和日常生活等方面。 关键词：一氧化碳。。。。。。。。。。Abstract The concentration level of carbon monoxide gas is one of the important signs that whether the Chemical factories ,coal mines and families happen natural disasters, and also an important factor of poisoning . Therefore, it is very necessary and quite common to set carbon monoxide gas detection alarm system in the factory and underground coal mine monitoring systems .If the ordinary gas concentration detector find the gas exceeds the standard ,the pulse signal output from voltage comparator will occur mutation .This trigger the location the alarm warning ,but technicians can’t know the gas concentration and the location of a gas leak. This paper describes the design of a roving concentration of gas detection circuit , Which includes DC power supply circuits, and signal detection concentration transform circuit switching control circuit, analog / digital converter circuit, figures show circuit and over-alarm circuit six parts. Can be detected and measured concentration ones synchronous display. The system works as follows : DC Power Supply for the entire circuit, sensors will be converted into concentration voltage signals, after a series of linear processing, analogue switch to the A / D converters, Finally, figures show circuit testing ones and the gas concentration. If concentrations exceed the limit, the alarm will alarm. This circuit is practical, high reliability and high precision measurement can be widely used in industrial, medical and health, env