What are the differences between semiconductor sensors and catalytic combustion sensors?

发表于2019-12-17

  1. Sensors are used in most products, but the effectiveness of different types of sensors varies. What is the difference between a semiconductor sensor and a catalytic combustion sensor? Let's see.


    Semiconductor sensor


    Semiconductor sensors are made by changing the conductivity at a given temperature and the composition of the surrounding gas. An alcohol detector, for example, works on the principle that when it encounters alcohol at high temperatures, its resistance is greatly reduced. It can effectively detect various gases, such as methane, ethane, propane, butane, alcohol, formaldehyde, carbon monoxide, carbon dioxide, ethylene, acetylene, vinyl chloride, styrene, acrylic acid, etc. In particular, this kind of sensor is cheap and suitable for civil gas detection.


    The following semiconductor gas sensors have been successful: methane (natural gas, methane), alcohol, carbon monoxide (urban gas), hydrogen sulfide, ammonia (including amines and terpenoids). High quality sensors can meet the needs of industrial inspection.


    Disadvantages of semiconductor sensors


    Poor stability, greatly affected by the environment, especially the selectivity of each sensor is not unique, unable to determine the output parameters. Therefore, it should not be used where precise measurements are required.

    Catalytic combustion sensor

    A catalytic combustion gas sensor was prepared on the surface of platinum resistance. At a certain temperature, the catalytic combustion gas burns on its surface. Combustion is the temperature rise of platinum resistance, resistance change, flammable gas change value. Catalytic combustion gas sensor selectively detects combustible gas: any combustible gas can be detected; If it is not flammable, the sensor will not respond. There are, of course, many exceptions. The catalytic combustion gas sensor has the advantages of accurate measurement, quick response and long service life. The output of the sensor is directly related to the explosion hazard of the environment.


    Disadvantages of catalytic combustion sensors


    There is no selectivity in the range of combustible gases. Working in a dark fire can cause an explosion. Most elements (organic vapors) are toxic to the sensor.