The Research Of Combustible Gas Detecting Alarm

Along with the development of technology, more and more combustible gas as a source of energy used in the industrial production and people's daily life. However, the combustible gas gives us great convenience, but it hides tremendous dangers. When combustible gas leaked out to the point of the explosion utmost, once a spark comes up, it will cause fires and explosion accidents, and induce serious economic losses, even life-threatening security.To reduce such incidents, we must right these combustible gas on-site real-time detection, adopt advanced and reliable safety testing instrument, closely monitored environment combustible gas concentrations, early detection of potential hazards. Take effective measures to avoid accidents, in order to ensure industrial safety and security of family life. Therefore, Research flammable gas detection and alarm combustible gas sensor technology has become the field of development is an important topic.At present, many cities in China have installed gas pipelines, the population of users is about 200 million people. The number of gas bases and transit stations is up to several thousand. If these domestic fuel, gas bases and transit stations for the alarm rate of 10%, the demand of Combustible Gas Detection Alarm reached over 20 million. Along with the entire community of fire and explosion safety of the importance of raising this figure will continue to grow. Over the past decade, the use of firedamp pools in rural areas has been a tremendous development. The end of 2006, the number of firedamp pools reached nearly 13 million. This detection of methane(the major components of firedamp) to provide the instruments of the market. Visibility, the Combustible Gas Detection Alarm is a very broad market prospects. The thesis of Combustible Gas Detection Alarm is in the design of in-depth research, referring to the domestic, international products and design ideas on the basis that a more reasonable choice of the system design, as well as a detailed analysis and presentation of equipment design and the various components.The design of this thesis, the Combustible Gas Detection Alarm is formed with the circuits of gas signal acquiring and control circuits of SCM.In the Combustible Gas Detection Alarm, select the 2M007-combustible gas sensor which is similar with general semiconductor sensors with the advantages of high sensitivity, fast response and Anti-jamming. Furthermore, the sensor sells with low prices and can be achieved at least three years which is more than the average semiconductor gas sensors.The core chip use STC12C5410AD which is smaller in size but with the similar price as the 8051, but the functions stronger than 8051. STC12C5410AD integrates A/D conversion, hardware multiplier, PWM and other functions, which with high-speed, Low-power, super interference advantages, it is higher than 8051 up to 8-12 times. It improved the alarm to the accuracy, reliability and anti-interference, without raising costs, and reducing the cubage of the alarm.Application procedures of the alarm uses C language, and make full use of chip resources, improve the measurement accuracy and code execution efficiency, reduce code capacity ,using the median value of the average digital filtering algorithm to A/D conversion by the digital signal filtering.The Combustible Gas Detection Alarm could work in a wide temperature range, and can display the concentration of combustible gas or flammable liquid vapor on the LCD display. When the concentration of the combustible gas or flammable liquid vapor reaches a certain level, the alarm sends lightening and sounds warning. It also has the function that self-diagnosis repeats rapid detection and the function of delaying alarm. Alarm could communicate with the Host Computer (PC), the concentration of gases can upload from the computer records, also can use the computer to complete the real-time control and measurement functions.On the basis of the alarm of this paper, could take an appropriate functional expansion so that the functions of the combustible gas detection alarm will be more perfect, more security, and more convenient. In order to further improve security, on the basis of the automatic sounds and lightening warning, use MCU to drive relays to control combustible gas pipeline valves, or shut down other device of leak gas.