Siemens RDG100 User Manual

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Siemens RDG100, RDG100T, RDG110, RDG140, RDG160 Basic Documentation CE1P3181en
Building Technologies Functions 14 Dec 2011
4.7.3 2-pipe fan coil unit
On 2-pipe applications, the thermostat controls a valve in heating / cooling mode
with changeover (automatic or manual), heating only, or cooling only. Cooling only
is factory set (P01 = 1).
ON/OFF control
The diagrams below shows the control sequence for 2-position control.
Heating mode Cooling mode
½ SDH
1
0
½ SDH
w
Y
3191D01
T[°C]
YHC
Y
½ SDC
1
0
½ SDC
w
3191D02
T[°C]
YHC
T[°C] Room temperature SDH Switching differential “Heating” (P30)
w Room temperature setpoint SDC Switching differential “Cooling” (P31)
YHC Control command “Valve” or “Compressor”
Modulating control: 3-position, PWM or DC 0…10 V
The diagrams below show the control sequence for modulating PI control.
Heating mode Cooling mode
XpH
100
0
w
Y [%]
3191D03
T[°C]
YHC
XpC
Y [%]
100
0
w
3191D04
T[°C]
YHC
T[°C] Room temperature XpH Proportional band “Heating” (P30)
w Room temperature setpoint XpC Proportional band “Cooling” (P31)
YHC Control command “Valve”
The diagrams only show the PI controller’s proportional part.
Setting the sequence and the control outputs
Refer to sections 4.5 ("Applications"), 4.7.1 ("Sequences") and 4.7.2 ("Outputs").
Control se
quence
on/off output
Control sequence
modulating output
Note

Siemens RDG100 Specifications

General

Brand	Siemens
Model	RDG100
Category	Thermostat
Language	English