ABB i-bus
®
KNX
Parameters
FCC/S 1.X.X.1 | 2CDC 508 200 D0211 Rev A 285
7.10.2.6.1
Limitations
When limitation is active, the fan speed can only operate between the values set for the parameter.
Limitation applies in both manual and automatic mode.
Note
For this function to work, the value of the lower limit must be less than or equal to the value of the
upper limit.
If the upper and lower limits are set to the same value, the fan stays permanently at that speed.
Note
The parametrized start-up behavior, which is a technical characteristic of the fan, takes priority
over limitation. In other words, if limitation is set to start at a fan speed of 40% and a start-up is
set to start at 60%, the fan will react as follows: The fan is in the OFF state and receives a control
signal to run at 20% speed. Initially, the fan speeds up to 60% (start-up speed), and then
switches to 40% as specified by the limitation. The limitation prevents the fan from reaching the
fan speed actually required – in this case, 20%.
There are three limitations available. They can be used, e.g., to prohibit speed 3 in hotel rooms
during the night so as to reduce background noise.
The sequence of the displayed limitations corresponds with their priorities, i.e. limitation 1 takes
highest priority, followed by limitations 2 and 3.
The following points apply to limitations:
•
The limitation need not necessarily apply to one fan speed only. It can encompass a range of
fan speeds, i.e. only certain speeds can be set if limitation is active. This provides scope for a
certain degree of adjustment.
•
Limitation is activated when the
Limitation
group object receives a telegram with the value 1,
and deactivated when it receives a telegram with the value 0.
•
When limitation is activated, the product switches to the parametrized fan speed regardless of
the control value. If another speed or a speed outside the limitation range is set when the func-
tion is activated, then the fan switches to the required speed, or to the speed limit for the range.
•
After a limitation is switched off, fan speed is recalculated and executed. This means that during
limitation, the product operates normally in the background, the outputs are not changed and
implementation only occurs once limitation ends.
Each of the three limitations used to limit the fan speeds has the same parameters.
Note
They are prioritized according to the listed sequence. The highest priority is assigned to limitation
1 and the lowest to limitation 3.
7.10.2.6.1.1
—
Dependent Parameter
Limitation x lower limit
Options:
0…100
This parameter determines the lowest permissible fan speed when limitation is activated.
