Basic Documentation

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Siemens Universal controllers RMU710B, RMU720B, RMU730B CE1P3150en
Building Technologies Temperature controller (basic type A) 03.10.2011
11.5 Room or extract air temperature control with
supply air limitation
Room temperature control with supply
air limitation
Extract air temperature control with
supply air limitation
N.X2
Y
SIGNAL Y
x
RT
N.X1
Y
SIGNAL Y
x
SAT
S3 S2 S1 S4 S5
yp yp yp yp yp
a
d
Controller 1
(Ventilation)
With supply air limitation
Cascade
Constant (supply air)
Cascade/const (alternating)
Seq. limit. Casc/Const

N.X1
Y
SIGNAL Y
x
EAT
N.X1
Y
SIGNAL Y
x
SAT
S3 S2 S1 S4 S5
yp yp yp yp yp
a
d
Controller 1
(Ventilation)
With supply air limitation
Cascade
Constant (supply air)
Cascade/const (alternating)
Seq. limit. Casc/Const

11.5.1 Operating principle
The room/extract air temperature is controlled to the set room setpoint via PID
control; supply air may vary within the set limitation values.
For most plants, we recommend to use room / supply air temperature cascade
control (PI-PI cascade) which always includes supply air limitation. Room /extract
air temperature control with supply air limitation is recommended only where
multistage aggregates with large load steps (e.g. 2-stage refrigeration machine with
dx expansion cooling) is to be switched.
11.5.2 Room setpoints
Specific setpoints can be predefined for operating modes Comfort, Precomfort
and
Economy.
Main menu > Commissioning > Settings > .... or
Main menu > Settings > Controller 1 > Room setpoints >
Main menu > Controller 1>
Operating line Range Factory setting
Economy cooling setpoint 30 °C
Precomfort cooling setpoint 28 °C
Comfort cooling setpoint 24 °C
Comfort heating setpoint 21 °C
Precomfort heating setpoint 19 °C
Economy heating setpoint 15 °C
If a room temperature is still available at selected extract air temperature control,
the room temperature is used for functions such as sustained mode, night cooling
or setpoint effects.
In case of room temperature control, the room temperature is available for
functions such as sustained mode, night cooling, and setpoint effects.
See Section 11.10
Re
commendation
Setting values
Note
Setpoint limitations