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Siemens
RXB (KNX) Applications library
CLC and RAD description of functions for CC-02 CM110384en_03
Building Technologies
Setpoint calculation
28 Feb 2009
6
Setpoint calculation
6.1
Description
•
Each room controller
knows
9 different room temperature setpoints
:
One heating and cooling setpoint each for the room operating modes
Comfort,
Precomfort, Economy,
and
Protection
as well as
Frost risk limit value
.
•
The setpoints are:
–
Defined
in the tool during engineering.
–
Adjusted
during runtime by the communication objects (DESIGO, Synco).
This does not apply to Protection setpoints and Risk of frost limit values
(page 31).
•
The setpoints are
shifted
:
–
Centrally
via KNX bus from the building automation and control system
(only
Comfort
,
Precomfort
and
Economy
).
–
Locally
via PPS2 by a room unit or a setpoint adjustment unit
(only
Comfort
and
Precomfort
).
– The controller controls the values internally to ensure that sensible periods are
adhered to between the various room operating modes.
•
The
result
are 8
present
setpoints.
•
The Effective room operating mode selects one value each for heating and cooling
from the 8 setpoints. These are the
effective
setpoints used by the controller.
Define
Shift
10
38
5Z
40
en
Comfort heating setpoint
Comfort cooling setpoint
Precomfort heating setpoint
Precomfort cooling setpoint
Economy heating setpoint
Economy cooling setpoint
Protection heating setpoint
Protection cooling setpoint
Local setpoint shift
Central setpoint shift heating
8
present
setpoints
Effective
heating setpoint SpH
Effective
cooling setpoint SpC
H
C
PPS2
KNX
Effective
room operating mode
Central setpoint shift cooling
Frost setpoint
KNX
KNX
KNX
KNX
PPS2
DI
KNX
KNX
(6.1.1)
(6.1.2)
