Catalytic Combustion Gas Sensor
This sensor is manufactured by coating a high-temperature resistant catalyst layer on the surface of a platinum resistor. At a specific temperature, flammable gases undergo catalytic combustion on the catalyst surface. The combustion raises the temperature of the platinum resistor and causes a change in its resistance, and the magnitude of this resistance change is a function of the concentration of the flammable gas.
Catalytic combustion gas sensors selectively detect combustible gases: they can measure any burnable gas and produce no response to non-combustible substances. Admittedly, there are numerous exceptions to the rule that all combustible gases are detectable, yet this selectivity generally holds true.
Catalytic combustion gas sensors deliver accurate measurement, fast response and long service life. Their output is directly correlated with the explosion risk of the surrounding environment, making them a dominant sensor type in safety detection applications.
Disadvantages
No gas selectivity among different flammable gases;
Operates with a hidden hot surface, which carries the risk of igniting gas mixtures and triggering explosions;
Most organic vapors can poison and deactivate the sensor.
Major suppliers of this sensor are located in China, Japan and the United Kingdom (the country where it was invented). China is currently the largest end user, mainly for coal mine applications, and also boasts leading domestic manufacturing technology for these sensors. Despite misleading promotional information from various distributors distorting public understanding of the product, the mainstream manufacturers of catalytic combustion gas sensors are based in China.
