ABB i-bus KNX Product Manual page 68

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ABB i-bus KNX
Commissioning
Note
Saving the last brightness value is undertaken with every OFF telegram except for the lighting groups
already switched off. In this case, with a further OFF telegram, the OFF state is not saved as the last
brightness value. In this case, with a further OFF telegram, the OFF state is not saved as the last
brightness value.
If a renewed switch OFF telegram is received during dimming down, the current brightness value is
saved as the last brightness value.
On light controller supply voltage failure, the information of the last brightness value is retained. With a
renewed ON telegram after light controller supply voltage recovery, the brightness value of the last OFF
telegram is still set.
The last brightness value is lost after a download or KNX bus voltage failure. After KNX bus voltage
recovery, the last brightness value is set to maximum brightness.
A differentiation is made between the last brightness value with central switching via the communication
object Switch (DALI output) and group-orientated switching via communication object Switch (Group x).
Both values are independent of each other. This means if some lighting groups are dimmed or switched
on or off via a central telegram, the last brightness values for the lighting group are retained without
change. When an ON telegram is received for the lighting group, the brightness value, which was set
with the last OFF telegram, is set again with the lighting group.
Minimal brightness value
Options:
This parameter defines the minimum brightness value, which the lamps of the lighting group assume. This
value is stored in the DALI devices and thus applies for all functions. If a minimum brightness value is set,
which exceeds the maximum brightness value, the minimum brightness value is set equal to the maximum
brightness value.
If the function Burn-in lamp is activated, the lamp group will be operated only with 0 % (OFF) or 100 %
brightness, regardless of this setting.
If a brightness value is received via the communication objects Brightness value and Brightness
value/status or Brightness value of Slave, which are below the defined minimum dimming value, the
minimum dimming value is set.
The Minimum brightness value also applies in the functions Staircase lighting and Scenes.
66 2CDC507128D0202 | DLR/A 4.8.1.1
100 % (255)
99 % (252)
...
1 % (3)