Advantages of laser methane sensors and other sensors

　　1，What are the advantages of laser methane sensors over electrochemical or thermal catalytic sensors?

　　Electrochemical/thermal catalytic sensors are usually sensitive elements in direct contact with gas. Through chemical reaction to produce heat or electricity to detect, is a kind of consumable sensor; The service life of the electrochemical/thermal catalytic sensor will shorten with the increase of detection gas frequency and concentration. Because it is based on chemical reactions, the electrochemical/thermal catalytic sensor will react to the same type of gas, without selectivity, and often cause false alarm.Because chemical reactions are sensitive to humidity, temperature, pressure and ambient gases, electrochemical/thermal catalytic sensors often cause the problem of zero drift for a variety of reasons, resulting in a short correction cycle.Frequent calibration increases the cost of using sensors purchased cheaply. The detection concentration of electrochemical sensor is less than 100ppm; The thermal catalytic sensor detects concentrations in the percentage range.In many practical applications, high dynamic measurement range is a must. If chemical sensors are used, sensors with different measuring ranges need to be installed, which increases the cost and is inconvenient to use.The measurement dynamic range of the laser gas sensor can meet the requirements of most test ranges. The laser sensor is an optical detector based on the detection principle of TDLAS. Under atmospheric pressure conditions, the laser sensor is not affected by changes in pressure and humidity, that is, intrinsically-safe, no cross interference, strong anti-humidity, anti-dust and anti-vibration. Free adjustment after delivery, long service life, fast response, small error measurement range.

　　2，What are the advantages of laser methane sensors over infrared sensors?

　　Infrared sensor uses the middle infrared light source as the detection light, and water molecules in the middle infrared region has a strong absorption characteristics, so the infrared sensor humidity resistance is poor;Infrared sensor light source signal is weak, usually need standard gas chamber and detection gas chamber to do difference to take out the effective signal, so the structure of the gas chamber is complex, anti-vibration ability is very weak, is not conducive to the use of coal mining area, and laser sensor no induction to water vapor, seismic ability is good. The light source of laser methane sensor is laser, which is a high efficiency light source at present.The infrared light source of the infrared sensor is the special filament heating into infrared radiation, and the infrared radiation only a trace of effective light can be used, so it takes a long time to integrate to measure the effective signal, so the response speed is very slow, and the response time of the laser methane sensor is 6-10 seconds. Compared with the infrared sensor, the laser methane sensor has fast response speed, strong anti-humidity and anti-vibration ability, and stable and reliable operation.