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Comet Temperature, humidity, CO2 transmitter with RS232 interface

Temperature, humidity, CO2 level sensor. Outdoor, indoor use.

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



  • Temperature
  • Relative humidity
  • Counted values (dew point…)
  • CO2


  • Measuring range -10 to +50 °C
  • Accuracy ±0.5 °C
  • Resolution 0.1 °C


  • Measuring range 5 to 95 % RH
  • Accuracy ± 2,5 % RH
  • Resolution 0.1% RH


  • Measuring range -60 to +80 °C
  • Accuracy ±1.6°C at ambient temperature T<25°C and RH>30%
  • Resolution 0.1 °C


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


          • Operating temperature -30 to +60 °C
          • Channels internal temperature, humidity and CO2 sensor
          • Counted values dew point, absolute humidity, specific humidity, mixing ratio, specific enthalpy
          • Range of humidity sensor temperature compensation all temperature range
          • Output RS232
          • Communication protocol ModBus RTU and Advantech ADAM compatible protocol
          • Power 9-30 Vdc
          • Protection class IP30 electronics, IP40 sensors
          • Dimensions 88,5 x 170 x 39,5 mm; stem length 75 mm
          • Weight approx. 150 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


          Comet Database One Click Installer (20.1-II)

          Database Viewer dbapi 20.1

          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


          3D model T6340

          Terms and Conditions COMET System s.r.o.


          Instruction Manual

          Declaration of Conformity

          Description of communication protocols of Tx3xx and Tx4xx transmitters with RS232 and RS485 communication interface


          CATALOG - CO2

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

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