Technical data

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Siemens RDG400KN Basic documentation CE1P3192en
Building Technologies Functions 20 Jul 2010
3.6.4 Single-duct
On single-duct applications, the thermostat controls an actuator (air damper, VAV
system, valve etc.)…
– in heating / cooling mode with changeover (automatic or manual),
– heating only mode,
– or cooling only mode.
Cooling only is factory-set (P01=1).
The output signal for the air flow can be limited to a minimum and maximum value
if required (see section 3.5 "Additional features").
Modulating
control: 3-position or DC 0…10 V
The diagrams below show the control sequence for modulating PI control.
Heating only (P01 = 0) Cooling only (P01 = 1)
max
min
XpH
Y
0%
100%
TR [°C]
W
H
Vmin
Vmax
max
min
Y
0%
100%
TR [°C]
XpC
W
C
Vmin
Vmax
Changeover (P01 = 2, 3)
max
min
Changeover
XpH
Y
0%
100%
TR [°C]
XpC
W
C
H
Vmin
Vmax
T[°C] Room temperature XpH Proportional band “Heating”
w Room temperature setpoint XpC Proportional band “Cooling”
Y Control command “Actuator” Vmin Min. limitation for output
Vmax Max. limitation for output
The diagrams show the PI controller’s proportional part only.
Setting the sequence and the control outputs
Refer to sections 3.4 "Applications", 3.6.1 "Sequences", and 3.7 "Outputs".
Note: