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Siemens RDG100…/RDG110…/RDG140.../RDG160… Basic Documentation CE1P3076.en
Building Technologies Functions 28 May 2009
Modulating control: 3-position, PWM or DC 0…10 V
The diagram below shows the control sequence for modulating PI control.
Heating mode
(automatic changeover = heating or heating only)
Cooling mode
(man. / auto. changeover = cooling or cooling only)
Y [%]
100
0
w
3181D122
T[°C]
YR
XpH
Y1
w
D
XpH
Y [%]
100
0
w
3181D123
T[°C]
Y1
XpH
YR
x
dz
XpC
T[°C] Room temperature XpH Proportional band “Heating” (P30)
W Room temperature setpoint XpC Proportional band “Cooling” (P31)
Y1 Control command “Valve” X
dz
Dead zone (P33)
YR Control command “Radiator” w
D
Setpoint differential (P34)
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