ABB i-bus KNX Product Manual page 187

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ABB i-bus KNX
Planning and application
The increment time should be selected so that the brightness change of a control step is available to the
DLR/S via the Light Controller/lighting equipment/Light Sensor before the next control step is triggered.
Otherwise the brightness setpoint will be exceeded and has to be regulated back a step.
Normally, the DLR/S determines these control variables. However, if required, these variables can be set
individually in the
parameter Changing brightness during lighting control, the Individual setting option is selected.
The parameterized variables are written in the following illustration.
In the start-up phase (1), the Step time for fast approach (T1) of the control step can be parameterized.
The smaller this time is, the faster the control steps are sent with the calculated step increment (Y1). The
setpoint brightness is approached in a relatively short time.
If the difference between the setpoint brightness and the actual brightness has undershot a parameterized
value, the fine tuning phase (2), in which the setpoint value is approached more slowly using Step time for
slow approach (T2), commences.
The increment (Y2) can also be parameterized, in order to reach the setpoint value more quickly or more
slowly. This increment only is valid until a determined interval to the setpoint value. This interval can be set
via the parameter Setpoint/actual diff., up to which control is with max. step width.
With an additional parameter (Setpoint/actual diff., up to which control is with max. step width), you set the
phase (3) in which light control is suspended. A range around the setpoint value, where there is no light
control, must be parameterized. Only when the actual brightness is again greater than this difference will
light control recommence. In this way, continuous control with the respective changes in brightness is
avoided. This generates a smoother and less abrupt response and considerably reduces the KNX bus load
with a master/slave control.
Parameter window - Gx Light controller, page 99. The parameters are enabled if, in the
DLR/S 8.16.1M | 2CDC 507 100 D0202 185