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Comet Temperature, humidity, CO2 transmitter with two relay and RS485 outputs


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Comet Temperature, humidity, CO2 transmitter with two relay and RS485 outputs

Temperature, humidity, CO2 level sensor 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



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


  • Measuring range -30 to +80 °C
  • Accuracy ±0.4 °C
  • Resolution 0.1 °C


  • Measuring range 0 to 100 % RH
  • Accuracy ±2.5 % RH from 5 to 95 % at 23 °C
  • Resolution 0.1% RH


  • Measuring range -60 to +80 °C
  • Accuracy ±1.5 °C at ambient temperature T <25 °C and RH >30 %
  • Resolution 0.1 °C

      CO2 SENSOR

      • 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 temperature, humidity and CO2 sensor
            • Counted values dew point, absolute humidity, specific humidity, mixing ratio, specific enthalpy
            • Acoustic alarm from built-in beeper - switchable
            • Output RS485
            • Range of humidity sensor temperature compensation all temperature range
            • Available temperature units degrees Celsius, degrees Fahrenheit
            • Communication protocol ModBus RTU and Advantech ADAM compatible protocol
            • Power 9-30 Vdc
            • Protection class IP30 electronics; IP40 sensors
            • Dimensions 136 x 213 x 45 mm; stem length 75mm
            • 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


            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


            Terms and Conditions COMET System s.r.o.


            Instruction Manual

            Quick Start Manual

            Declaration of Conformity


            CATALOG - CO2

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

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