The maintenance-free microprocessor-controlled duct sensor AERASGARD® KTM - CO2 - SD with automatic calibration is used for detecting the CO2 content of the air within a range of 0...2000 ppm or 0...5000 ppm as well as the temperature within a range of –35...+80 °C. The measured values are converted into standard signals of 0 -10 V.