ABB i-bus FCC/S 1 1 Series Product Manual page 273

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ABB i-bus KNX
Parameters
Behavior of the fan with overlapping switching thresholds due to usage of hysteresis
1) The hysteresis defines the speed at which the speed set is left.
2) If the speed is left, the new speed is determined using the control value and the switching
3) A control value with the value 0 always results in speed 0.
Example 1:
Parametrized:
Threshold OFF <-> Speed 1 = 10 %
Threshold Speed 1 <-> Speed 2 = 20 %
Threshold Speed 2 <-> Speed 3 = 30 %
Hysteresis 15 %
Behavior when ascending from speed 0:
•
•
•
Behavior when descending from speed 3:
•
•
•
If a switching point is less than or equal to the changeover point 1 <-> 0, the speed is skipped on
switching down.
Example 2:
Parametrized:
Threshold OFF <-> Speed 1 = 1 %
Threshold Speed 1 <-> Speed 2 = 10 %
Threshold Speed 2 <-> Speed 3 = 20 %
Hysteresis 20 %
Behavior when descending from speed 3:
•
•
•
•
At a speed of 100 %, the highest fan speed is always used. This feature is intended to prevent
undesirable incorrect behavior due to erroneous programming.
Note
thresholds. The hysteresis is not taken into account. Control values are rounded to whole per-
centages by the device.
Speed 0 is left at 25 % (≥ 10 % + hysteresis).
The new speed is 2 (25 % is between 20 % and 30 %).
Accordingly, speed 1 is omitted.
Speed 3 transition at 14 % (< 30 % – hysteresis).
The new speed is 1 (15 % is between 10 and 20 %).
Accordingly, speed 2 is omitted.
Speed 3 is left at 20 % (40 % - hysteresis)
New speed is 2
Speed 2 is left at 0 % (20 % - hysteresis)
New speed is 0, speed 1 is skipped
Note
FCC/S 1.X.X.1 | 2CDC 508 200 D0211 Rev A 273