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Siemens
RDU341 Basic Documentation
CE1P3172en
Building Technologies
2015-06-08
3. Functions
3.1 Temperature
control
Setting of the control parameters (P01, etc., mentioned throughout the document)
is described in section 3.12.
The thermostat acquires the room temperature via built-in sensor, external room
temperature sensor (QAA32), or external return air temperature sensor (QAH11.1),
and maintains the setpoint by delivering actuator control commands to heating
and/or cooling equipment. The following control outputs are available:
·
VAV box / damper:
Modulating PI/P control with DC 0...10 V
·
El. heater:
ON/OFF control (2-position)
The switching differential or proportional band is 2 K for heating mode and 1 K for
cooling mode (adjustable via parameters P30 and P31).
The integral action time for modulating PI control is 5 minutes (adjustable via
parameter P35).
The display shows the acquired room temperature or the Comfort setpoint, selecta-
ble via parameter P06. The factory setting displays the current room temperature.
Use parameter P04 to display the room temperature or setpoint in °F rather than
°C as needed.
The acquired room temperature (internal or external sensor) is also available as
information on the bus.
·
With automatic changeover or continuous heating / cooling, symbols
/
indicate that the system currently heats or cools (heating or cooling output is
activated).
·
With manual changeover (P01 = 2), symbols
/
indicate that the system
currently operates in heating or cooling mode. Thus, the symbols are displayed
even when the thermostat operates in the neutral zone.
Concurrent display of the current temperature or setpoint in °C and °F (parameter
P07 = 1) is possible on the thermostats.
The outside temperature can be displayed on the room thermostat by setting
parameter P07 = 2. This temperature value has only information character.
In LTE mode, the outside temperature can only be received on outside temperature
zone 1.
In S-mode, the corresponding communication object needs to be bound with a
KNX sensor device.
Time of day via bus can be displayed on the room thermostat by setting parameter
P07 = 3 or 4. The display format is either in 12- or in 24-hour format.
The information can be received from a Synco controller with time master
functionality or any other KNX device if the corresponding communication object is
bound.
General note:
Parameters
Temperature control
Display
KNX
R
Room temperature
/
Concurrent display of
°C and °F
KNX
R
Outside temperature via
bus
KNX
R
Time of day via bus
