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Building Technologies
Basic documentation: Communication via the KNX bus
CE1P3127en
HVAC Products
Appendix
30.08.2007
9.2.2 Changeover
via analog input
The outside temperature sensor is wired to universal input "x"(configured as an
analog input) of the "H/C changeover" function block in controller 1 (RMU7x0B).
The release relay in controller 1 affects the generation of heating/refrigeration
energy. The heating/cooling changeover signal affects all controllers (in this case
controller 1 and controller 2) in the same heating/refrigeration distribution zone.
If the source of the H/C changeover is an analog signal, then two limit values must
be selected for the changeover. For further information refer to the basic
documentation, manual P3150.
1
M
T
1
KNX
2
M
2
T
T
2
S1
S1
S1
S2
S2
x
S2
S3
Q
Y
d
1
2
3
9
x
Kältebedarf
Q
Y
d
S4
S4
S4
S5
1
2
3
9
x
Q
23
9
1
S1
S1
S1
S2
S2
x
S2
S3
Q
Y
d
1
2
3
9
x
Kältebedarf
Q
Y
d
S4
S4
S4
S5
1
2
3
9
x
Q
23
9
T
AI
Htg/ClgCoil 1
Htg/ClgCoil 2
31
2
7
S
0
4
e
n
Flow
Return
H/C changeover signal
Heat/refrig distribution zone 1
H/C changeover
Heat demand
Supervision
Controller
Controller
Supervision
Refrig demand
H/C changeover
Heat demand
Supervision
Controller
Controller
Supervision
Refrig demand
Changeover source
analog input AI
Note