CDT-MOD-2000 Duct

CO2 transmitters with temperature output for duct that use Modbus serial communication protocol

CDT-MOD-2000 Duct combines CO2 and temperature measurements in one device installed in air ventilation duct. Illuminated display ensures easy readability also from a distance. The CDT-MOD-2000 Duct has a screwless lid and an easily adjustable mounting flange that make the installation of the device easy.


The CDT-MOD-2000 Duct series transmitters calibrate themselves automatically using ABC logicTM. The ABC logicTM requires that the space in which the transmitter is used needs to to be unoccupied for four hours per day so that the indoor CO2 concentration drops to the outside level. CDT-MOD-2000-DC Duct is a dual channel model with a measuring channel and a reference channel that makes a continuous comparison and the necessary adjustment accordingly. CDT-MOD-2000-DC Duct is also suitable for buildings that are continuously occupied.


CDT-MOD-2000 Duct series devices include:

• Separate Modbus output for each measurement parameter (CO2 and T)

• Offset feature enabling field calibration for each measurement parameter (CO2 and T)

• Mounting flange

• Clear backlit display

Technical details

Communication: RS-485 Modbus (RTU)
Accuracy: CO2: ±40 ppm + 3 % of reading, DC model: 75 ppm or 10 % of reading (whichever is greater)
Temperature: <0.5 °C
Measuring elements: NTC10k temperature sensor, Non Dispersive Infrared (NDIR) CO2 sensor
Measuring units: ppm, °C
Calibration: Automatic self-calibration, ABC LogicTM or continuous comparison (DC)
Supply voltage: 24 VDC/VAC ±10 %
Current consumption: max 230 mA (at 24 V) + 10 mA for each voltage output
Operating temperature: 0...+50 °C
Protection standard: IP54

CDT-MOD-2000 Duct

CDT-MOD-2000 Duct-D


Product series

Carbon dioxide transmitter, analog outputs
Carbon dioxide transmitter, Modbus communication


ABC logic™, Automatic Background Calibration
Dual channel, for continuously occupied space


Duct mount


With display
Without display

Other Modbus products: