CO2DT( R)
CO2DT(-R)
CO2DT(-R)
CO
2
-transmitter for duct mounting
• Infrared technology (NDIR)
• CO
2
-level 0...2000 ppm measuring range
• Good long term stability
Duct transmitter for measuring carbon dioxide
concentration in air. Measuring range 0...2000 ppm and
output signal 0...10 V DC (CO2DT) or relay output
(CO2DT-R).
• Simple installation and service friendly housing
• Probe only 12 mm diameter
• Auto-calibration
CO2DT and CO2DT-R are CO
2
-transmitters with
patented auto-calibration, intended for duct mounting.
The sensing element is mounted in the cover-part of the
casing and the probe is in the shape of a venturi tube with
two air channels.
The air in the ventilation duct is transported to the
sensing element through one half of the probe and then
back to the duct through the other half.
Mounting
To ensure proper function, make sure that that the cover
is properly fastened and that the cable gland makes a tight
seal around the cable.
The transmitter should be placed in the air flow direction
of the ventilation duct according to the marks on the
cover.
Applications
The CO
2
-level gives a direct indication of the indoor
air quality. This information can be used to control
ventilation with high precision and improve the air
quality. By increasing the supply air only when it is
necessary, it is possible to minimise energy costs.
CO2DT(-R) can for example be used to control
ventilation in residential and office areas.
Measuring principle
The CO
2
-concentration is measured with infrared light.
This technique has several advantages:
• Very high accuracy
• Exact identification of the detected gas
• Low risk of contamination
• Short response time
• Good long term stability
Automatic calibration
CO2DT(-R) is calibrated automatically, which means that
manual recalibration is not required during the lifetime of
the sensor.
Supply voltage and output
The supply voltage is 24 V AC/DC and the output
signal is 0….10 V DC (CO2DT) or change-over relay
(CO2DT-R).
Hysteresis and level for CO2DT-R
switching off
ppm
2000
1000500
relay status
switching
on
ON
OFF
Hysteresis [% of measuring range]
Level [% of
measuring range]
25% of
measuring
range
revision
12 2010