ABB i-bus KNX Product Manual page 20

3.4.6 C ontrol system
3 2 B
Designation
Fan coil system used
Switchover betw. heating
and cooling*
Setting the control
parameters
System type for heating
system
System type for cooling
system
* Can only be set with 4-pipe systems.
With a 2-pipe system, the switchover is always carried out via object 15 .
** Change since the last send
Values
2-pipe system
4-pipe system
automatic
via object
via system type
user-defined
Radiator heating
Fan coil unit
Cooling ceiling
Fan coil unit
Meaning
There is only one water
circuit which circulates the
cooling or heating medium
depending on the time of
year.
The system consists of 2
separate water circuits for
heating and cooling.
RTF/A 1.1 automatically
changes to cooling mode
when the actual
temperature is above the
set value
The cooling mode can
only be activated on the
bus side via object 15 (1=
cooling).
When this object is not set
(= 0), the cooling mode
remains switched off.
In the 2-pipe system ⇒,
always via object.
Standard application
Professional application:
P /PI controller
H U U H
parameterised on own
account
PI-controller with:
Integration time = 90
minutes
Strip width = 2.5 K
Integration time = 180
minutes
Strip width = 4 K
PI-controller with:
Integration time = 90
minutes
Strip width = 2.5 K
Integration time = 180
minutes
Strip width = 4 K
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