How are the core gas sensors of gas detectors classified?
Gas detectors are widely used in construction sites, industrial plants, and places with severe pollution in daily life. The core part of gas detectors is gas sensors. So, what is the classification of the technical field of gas sensors?
2. Electrochemical gas sensor
Electrochemical gas sensors are like a name, they measure the concentration of gases by testing the current. The advantages of electrochemical gas sensors are high sensitivity and good selectivity of gases, but the disadvantage is that their service life is usually around two years.
3. Catalytic combustion gas sensor
Combustion gas sensors are not very sensitive to non combustible gases, so their basic application field is to detect combustible gases. Therefore, they are generally used to monitor combustible gases in petroleum and petrochemical, chemical plants, tobacco companies, and other industries. Its working principle is that gas sensitive materials burn under the action of electricity, and the combustibility is affected by the catalyst. The electric heating wire generates temperature due to the combustion, thereby changing its resistance value.
4. Optical gas sensor
Phosgene sensors mainly include infrared absorption type, spectral absorption type, fluorescence absorption type, etc., mainly including infrared absorption type. Measuring the infrared absorption wavelength can detect gases, as different gases have varying degrees of absorption of infrared waves. Now, due to its structural connections, the cost is generally quite high.
5. Solid state electrolyte gas sensor
Solid electrolyte is a type of chemical battery that uses solid ion conductivity as the electrolyte. It lies between semiconductors and electrochemistry. Selectivity and sensitivity are higher than semiconductors, and the lifespan is longer than electrochemistry, so it is applied in many aspects. The disadvantage is that the response time is long.
