Art. No. SC 1000 KNX
4.2.4.4 Light scene function
The device can be used in two different ways as part of a scene control system...
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Every sensor surface on the device display in the form of a KNX channel can work as a
scene extension (configuration-dependent). This feature makes it possible to recall or to
store scenes which are stored in other devices (see page 99-100).
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The device can independently store up to eight scenes with eight actuator groups. These
internal scenes can be recalled or stored via the device's own sensor surfaces (internal
scene recall) as well as via the communication object "B. scenes - extension input".
In the following subsections the internal scene function will be dealt with in greater detail.
Scene definition and scene recall
If the internal scenes are to be used, the parameter "Scene function ?" must be set to "Yes" on
the "Scene" parameter node.
The matching data types for the eight scene outputs must then be selected and adapted to the
actuator groups used. The types "Switching", "Value (0 … 255)" or "Value / blind position (0 …
100 %)" can be selected. As a rule, Venetian blinds are controlled via two scene outputs. One
output controls the blind height and the other one adjusts the slat position.
There is a separate parameter node available in the ETS for each scene output. The data types
can be selected in this node using the parameters of the same name. The ETS sets the
corresponding communication objects and the additional parameters of the scene commands.
The scene parameters can be set in the parameter node of a scene output for each individual
scene ("scene 1 … 8"). The setting options are the same for all 8 scenes.
It is possible that the values for the individual scenes preset by the parameters are modified
later on with the storage function (see page 223) when the system is in operation. If the
application program is then loaded again with the ETS, these locally adapted values will
normally be overwritten by the parameters. Due to the fact that it may take considerable efforts
to readjust the values for all scenes in the system, the parameter "Overwrite scene values
during ETS download ?" offers the possibility of retaining the scene values stored in operation
without overwriting them.
The internal scenes can be recalled directly via the device's own sensor surfaces of the channel
functions (Function "Internal scene recall) as well as from another bus device via the
communication object "B. scene extension input". This 1 byte communication object supports
the evaluation of up to 64 scene numbers in compliance with the KNX data point type 18.001
(SceneControl). For this reason it must be specified which of the external scene numbers
(1 … 64) is to recall the internal scene (1 … 8). This specification is made using the
parameters "Recall scene 1...8 via extension object with scene number" in the "Scenes
" parameter node. If the same scene number is listed for several internal scenes at this point, it
is always only the first of these scenes that will be activated (scene with the lowest scene
number).
In some situations there may be the requirement that a group of actuators is not controlled by
all, but only by certain scenes. A classroom, for instance, may require open blinds for the
"Welcome" and "Break" scenes, closed blinds in the "PC presentation" scene and no change in
the "Discussion" scene. In this example, the parameter "Permit transmission ?" in the parameter
node of a scene output can be set to "No" for the "Discussion" scene. The scene output is then
deactivated during the corresponding scene.
The parameter "Transmit delay" permits an individual waiting time for each scene output. This
transmit delay can be used in different situations...
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When the actuators participating in a scene transmit status messages automatically or
when several scene buttons are used to increase the number of channels within the
scenes, the recall of a scene may result for a short time in high bus loading. The transmit
delay helps to reduce the bus load at the time of scene recall.
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Sometimes, it is desirable that an action is started only after another action has ended. This
can be for instance the illumination which is to shut off only after the blinds/shutters have
been raised.
The transmit delay can be set separately for each scene output in the parameter group of a
scene. The transmit delay defines the time delay between the individual telegrams during a
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Software "Smart Control 501511"
Functional description
