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ABB i-bus
®
KNX
Project design and programming
The DALI Gateway can also be operated as a slave. In
slave mode,
the
channel is priority controlled via an 8-bit communication object. This opera-
ting mode is activated and deactivated per channel (DALI output) as
required via a communication object “Channel X - Slave Operation On / Off”.
In slave mode, it is possible to implement central lighting control in addition
to the standard dimming functionality. A master control unit (e.g. the lighting
controller LR/S 2.2.1 or presence detector PM/A 2.1) sends brightness va-
lues in an 8-bit format which controls the DALI output via the DALI Gateway.
The 1-byte control value is transferred to the DALI Gateway via the commu-
nication object “Channel X - Set Brightness Value”.
After switching on slave mode (value “1” at the communication object
“Channel X - Slave Operation On / Off”), the last brightness value received
by the communication object “Channel X - Set Brightness Value” is set.
If slave mode is switched on, the brightness can only be controlled via the
object “Channel X - Set Brightness Value”. The communication objects
“Channel X - On / Off” and “Channel X - Relative Dimming” are disabled
i.e. telegrams received at this object are not executed.
After switching off slave mode (value “0” at the communication object
“Channel X - Slave Operation On / Off”), the current brightness value is
retained. The control of the channel via the objects “Channel X - On / Off”
and “Channel X - Relative Dimming” is enabled again.
Central control has a higher priority than slave mode. After switching off the
central control function, operation reverts to slave mode again.
4.3.2.3 „Slave“ mode