In recent years, China's natural gas industry has developed rapidly. Liquefied gas, natural gas, coal gas and other urban gas as clean energy have been widely used in industry, commerce and urban residents. Especially with the rapid progress of the West-East Gas Pipeline Project, the development potential of the natural gas industry is huge. The promotion and application of urban gas has undoubtedly played a huge role in improving the quality of urban environment and the quality of life of residents. However, with the wide application of gas, explosion, poisoning and fire accidents caused by gas leakage also occur from time to time, which increases the insecurity and instability of the city to a certain extent. In order to make gas better benefit the people and society, reduce and eliminate all kinds of explosion and fire accidents caused by gas leakage, it is necessary for all gas users and residents to select appropriate gas alarms.
First of all, we should understand the type of gas alarm specified in the national standard. The gas alarm can be divided into four series of products: combustible gas leak detector (hereinafter referred to as leak detector), combustible gas alarm controller (hereinafter referred to as controller), combustible gas detector (hereinafter referred to as detector), and domestic combustible gas alarm (hereinafter referred to as alarm).
The leak detector is small and can be carried or held. It is mainly used for leak detection and line patrol of gas management. In case of gas leakage, the leak detector will give an audible and visual alarm and digitally display the gas concentration, so that safety measures can be taken in time to prevent the occurrence of malignant accidents such as explosion.
The controller+detector can monitor the gas concentration for a long time at the explosion-proof site. Detector, installed in explosion-proof places; The controller is hung in the duty room and other manned places, and the two are connected by shielded cables. When the field detector detects gas leakage, the signal is transmitted to the controller through the shielded cable, and the controller sends an audible and visual alarm. At the same time, the exhaust device can be started or the solenoid valve can be closed to cut off the air source, so as to achieve the purpose of safety. This instrument is widely used in industrial places such as liquefied gas stations, automobile gas stations, boiler rooms, etc.
The gas alarm is a household gas alarm, which is generally installed in the kitchen. In case of gas leakage, the alarm can give audible and visual alarm, or be accompanied by digital display and linked with external equipment. Some alarms can automatically open the exhaust fan to discharge the gas to the outside. Some alarms will automatically close the gas valve when giving an alarm to prevent continuous gas leakage
The core of gas alarm is gas sensor, commonly known as "electronic nose". When the gas sensor encounters gas, the resistance of the sensor changes with the gas concentration, and then generates an electrical signal for the subsequent circuit of the gas alarm. After being processed by electronic circuit, it becomes a voltage signal with proportional change in concentration, which is compensated by linear circuit to linearize the signal. After microcomputer processing and logic analysis, various control signals are output, that is, when the gas concentration reaches the alarm setting value, the gas alarm will send out audible and visual alarm signals to display the gas concentration or start external intermodal equipment (such as exhaust fan and solenoid valve).