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Siemens
RDG400KN,RGD405KN Basic documentation
CE1P3192en
Building Technologies
2017-02-17
On the RDG405KN, the analog input U1 can be used for different purposes. This
input can be set via P40.
#
Function of input
Description
0
Not used
No function.
1
Input for air damper
position
See section above "Air damper position VAV via
U1"
2
Input
IAQ
sensor
Input for an external analog CO
2
/VOC sensor.
This input is calibrated for a sensor range of
0…2000 ppm and cannot be set.
∂
The U1 value is always available on the bus via S-Mode object (e.g. object 36
on the RDG400KN and RDG405KN), even with selection P40 = 0
∂
The thermostat does not make a distinction between the DC 0...10 V signal from
a CO
2
sensor and that from a VOC sensor
3.9 Handling
faults
When the room temperature is outside the measuring range (that is above 49 °C or
below 0 °C), the limiting temperatures blink, e.g.
0 °C
or
49 °C
.
In addition, the heating output is activated if the current setpoint is not set to OFF,
the thermostat is in heating mode and the temperature is below 0 °C.
For all other cases, no output is activated.
The thermostat resumes Comfort mode when the room temperature returns to
within the measuring range.
For fault status messages on the bus, refer to section 3.10.11.
3.10 KNX communications
The RDG..KNX room thermostats support communications as per KNX
specification.
S-Mode
Standard mode; engineering via group addresses
LTE-Mode
Logical Tag Extended mode, for easy engineering,
used in connection with Synco
3.10.1 S-Mode
This mode corresponds to KNX communications.
Connections are established via ETS by assigning communication objects to group
addresses.
3.10.2 LTE-Mode
LTE-Mode was specifically designed to simplify engineering. Unlike with S-Mode,
there is no need to create the individual connections (group addresses) in the tool.
The devices autonomously establish connections.
Input U1 (RDG405KN)
KNX
R
Notes
Temperature out
of range
KNX
R
