The transmitter is designed for the measurement of carbon dioxide (CO2) and temperature (T) in HVAC applications. It incorporates
a dual wavelength NDIR CO
2
sensor, which compensates for ageing effects, is highly insensitive to pollution and offers outstanding
long term stability.
The transmitter is only available with CO
2
output (0-10V or 4-20mA) or with CO
2
and T passive outputs (0-10V or 4-20mA) or with
CO
2
and T active outputs (0-10V) and an additional passive T output.
GENErAL
•
The transmitter shall not be exposed to extreme mechanical or thermal stress.
Installed into a duct, a small amount of air will flow through the divided probe into
the transmitter housing, where the CO
2
sensing cell is located, and back into the
duct. The temperature sensor is located inside the probe.
Very important
For accurate measurement the cover as well as the cable outlet – cable glad or
conduit adapter - must be tightly closed. This is essential for avoiding ingress of
air other than from the duct into the enclosure, which would falsify the measure-
ment.
cAUtIoN
oPErAtIoN PrINcIPLE
USER‘S GUIDE
907021/850 – CO
2
- and Temperature Transmitter for Duct Mounting
INStALLAtIoN
The direction of the air flow in the duct shall correspond to the
direction indicated with arrows on the cover.
Recommended mounting screws:
ST4,2x50 DIN7981C
FOR CABLE GLAND
M16x1,5
CONDUIT KNOCKOUT
RUBBER GASKET
80.6mm 3.17“
Ø > 13mm
Ø > 0.51“
A...according to ordering guide
A
101mm
3.98“
19mm
0.75“
60
±0.3
mm
2.36
±0.11
“
Ø > 16mm
Ø > 0.63“
6mm
0.24“
90
±0.3
mm
3.54
±0.11
“
46mm
1.81“
5mm
0.2“
Cable gland:
Use a matching wrench to install the cable gland (in the scope of supply) onto the enclosure. While doing this the
blind will knock open. Do not use other, pointed, tools to knock open the blind in order to avoid damaging the electronics inside the
enclosure.
coNNEctIoN dIAGrAM
CO
2
sensing cell
Temperature sensor
