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Comet CO2 Concentration Transmitter with RS485 and two relay outputs


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Comet CO2 concentration transmitter with RS485 and two relay outputs

CO2 level transmitter with two output relays.

Green LED shines - CO2 concentration 0 to 1000 ppm
Yellow LED shines - CO2 concentration 1001 to 1200 ppm
Red LED shines - CO2 concentration 1201 ppm and more



  • CO2


  • Measuring range 0 to 2000 ppm
  • Accuracy ±(50ppm +2% from reading) at 25°C and 1013hPa
  • Resolution 1 ppm


  • Quantity 2
  • Maximal voltage 50 V
  • Maximal current 2 A
  • Maximal power 60 VA


  • Operating temperature -30 to +60 °C
  • Channels internal CO2 sensor
  • Acoustic alarm from built-in beeper - switchable
  • Output RS485
  • Communication protocol ModBus RTU and Advantech ADAM compatible protocol
  • Power 9-30 Vdc
  • Protection class IP30
  • Dimensions 136 x 150 x 45 mm
  • Weight approx. 360 g
  • Warranty 3 years


* the features may vary depending on the device type

  • accurate measurement of Temperature, Relative humidity, Dew point, Atmospheric pressure, CO2, Two-state events
  • industrial or interior design with protection up to IP65
  • integrated sensors, external probe, duct mount design
  • relays output 250Vac / 8A or 50 V on selected models


TSensor (3-4-1-0)

Sensor Reader (2-0-6-0)

Sensor RS485/232 utility (1-0-0-15)

Conversions - application for recalculation of values


Terms and Conditions COMET System s.r.o.


Instruction Manual

Quick Start Manual

Declaration of Conformity



CATALOG - Digital sensors and regulators with serial RS485/RS232 output

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