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Siemens RDG100…/RDG110…/RDG140.../RDG160… Basic Documentation CE1P3076.en
Building Technologies Functions 28 May 2009
Modulating control: 3-position or PWM
The diagram below shows the control sequence of modulating PI control.
Heating mode with manual selection (P01=2) Cooling mode with manual selection P01=2)
Y [%]
100
0
w
3181D1124
T[°C]
XpH
Y1
Y2 (YE)
w
D
½ SDH ½ SDH
3181D105
Y [%]
100
0
w
T[°C]
Y3
XpC
Heating and cooling mode (P01=4)
T[°C] Room temperature
w Room temperature setpoint
Y2 Control. command “El. heater"
(only on/off)
Y1 Control command “Valve” or “Comp.” (H)
(only PWM, not 3-position)
Y3 Control command “Valve” or “Comp.” (C)
XpH Proportional band “Heating” (P30)
XpC Proportional band “Cooling” (P31)
X
dz
Dead zone (P33)
Y [%]
100
0
w
3181D114
T[°C]
Y3
XpH
Y1
XpC
½
x
dz
½
x
dz
Y2 (YE)
w
D
½ SDH ½ SDH
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).
• Y1 can only be on/off or PWM
• Y2 can only be on/off
• Y3 can be on/off, PWM or 3-position
Note
Notes