Basic Documentation

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Siemens Universal controllers RMU710B, RMU720B, RMU730B CE1P3150en
Building Technologies Aggregates 03.10.2011
2. Changeover at an adjustable value
Here, an analog input must be assigned to MECH input 1. (Typically: outside
temperature or enthalpy difference outside air – extract air).
If the adjusted MECH limit value is exceeded, the output is inverted.
Control by heating sequences (S1, S2, S3)
w
Y
Q
S
3150S30en
OT > MECH limit value
OT < (MECH limit value - hysteresis)
Control by cooling sequences (S4, S5)
AO
AI
X...
T
12 1 2
Y
y1 y2 a

xa a
Q
Y...
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
3150s45en
OT
MECH
HR
CC....................
w
Y
Q
S
3150S31en
OT > MECH limit value
OT < (MECH limit value - hysteresis)
3. Changeover at an adjustable difference between two measured values
Here, one analog input each must be assigned to "MECH input 1" and "MECH
input 2". (Typically: MECH input 1 = Outside temperature, MECH input 2 = Extract
air temperature).
The output is inverted if as shown in this example the outside temperature is
greater than extract air temperature plus MECH limit value. The hysteresis is a set
1 K.
Control by heating sequences (S1, S2, S3)
w
Y
Q
S
3150S32en
OT > ( EAT + MECH limit value)
OT < (EAT + limit value - hysteresis)
Control by cooling sequences (S4, S5)
AO
AI
T
Y...
T
X... X...
12 1 2
Y
y1 y2 a

xa a
Q
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
3150s46en
OT EAT
MECH
HR
CC....................
w
Y
Q
S
3150S33en
OT > ( EAT + MECH limit value)
OT < (EAT + limit value - hysteresis)