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Siemens
RDG400KN,RGD405KN Basic documentation
CE1P3192en
Building Technologies
2017-02-17
# Function of
input
Description
Type
X1
Type
DI
KNX
R
Enable elec-
tric heater
5 Enable electric
heater
Digital input to enable/disable the electric heater via
remote control.
Enable electric heater is also possible via bus.
In this case, the function must not be assigned to any
local input X1-D1 (also refer to section 3.6).
DI
DI
KNX
R
Fault
information
6 Fault
Digital input to signal an external fault (example: dirty air
filter).
If the input is active,
ALx
is displayed and a fault is sent
on the bus (also refer to section 3.10.11).
(Alarm x, with x = 1 for X1, x = 3 for D1).
Note: Fault displays have no impact on the thermostat's
operation. They merely represent a visual signal.
DI
DI
KNX
R
D1, X1
(Digital)
7 Monitoring input
(Digital)
Digital input to monitor the state of an external switch
via bus.
DI
DI
KNX
R
X1, (Temp.)
8 Monitoring input
(temperature)
Sensor input to monitor the state of an external sensor
(e.g. QAH11.1) via bus.
AI
--
KNX
R
Presence
detector
9 Presence
detector
(RDG405KN
only)
Presence detector input switches the operating mode to
Comfort when the room is occupied and switches back
to Economy when the room is unoccupied.
Presence detector is also possible via bus. In this case,
do not assign the function to any local input X1-D1 (also
refer to section 3.2.1).
DI
DI
∂
Operational action can be changed between normally open (NO) and normally
closed (NC) via P39 (or P43 if a digital input)
∂
Each input X1 or D1 must be configured with a different function (1…5).
Exception: 1 or 2 or 3 inputs can be configured as fault (6) or monitoring input
(7, 8)
∂
X1 is factory-set to "External sensor" (1) and D1 to "Operating mode
switchover" (3)
For more detailed information, refer to section 0.
∂
For inputs X1-D1, one physical switch can be used for up to 20 room
thermostats (parallel connection).
Caution! Do not mix X1 (mains potential) and D1
∂
For sensors on inputs X1-D1, the cable length is max. 80 m
The information about the thermostat's damper position can be used to influence
the fan speed of a primary air handling unit. The thermostat receives the damper
position from a damper actuator or a VAV compact controller as a DC 0...10 V
signal using input U1. The damper position (0...100%) is sent on the bus.
An RMU7.. primary controller uses the LTE information of all connected room
thermostats to calculate the total air flow demand.
The state of U1 can be monitored via communication object 36 "U1".
The present air damper position is transmitted on the KNX bus.
For communication settings (geographical zone, air distribution zone), see sections
3.10.2 and 3.10.3.
Installation
Air damper position
VAV via U1
(RDG400KN
RDG405KN)
KNX
R
U1 (0...100%)
VAV air damper
position
(KNX LTE-Mode only)
(RDG400KN,
RDG405KN)