Siemens RDG100T - Page 34

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Siemens RDG100, RDG100T, RDG110, RDG140, RDG160 Basic Documentation CE1P3181en
Building Technologies Functions 14 Dec 2011
Modulating control: 3-position, PWM or DC 0…10 V
The diagrams below show the control sequence of modulating PI control.
Heating mode (P01=0) Cooling mode P01=1)
w
XpH
Y
YHC1
TR [°C]
XpH
YHC2
0%
100%
3181D18
w
D
Y
0%
100%
TR [°C]
XpC
YHC2
XpC
YHC1
3181D19
w
w
D
Changeover (P01=2 or P01= 3)
T[°C] Room temperature
w Room temperature setpoint
YHC1 Control command “Stage 1"
YHC2 Control command “Stage 2”
XpH Proportional band “Heating” (P30)
XpC Proportional band “Cooling” (P31)
X
dz
Dead zone (P33)
w
D
Setpoint differential (P34)
XpH
Y
TR [°C]
XpH
XpC
XpC
Changeover
0%
100%
YHC1YHC2
YHC1
YHC2
3181D20
w
w
D
w
D
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").
Note