ABB i-bus KNX Product Manual page 134

®
ABB i-bus KNX
© 2008 ABB STOTZ-KONTAKT GmbH
Planning and application
Brightness
Setpoint
brightness
Y1 = increment
Actual
brightness
T1
Step time
In the start-up phase (1) the increment time (T1) of the control step can be
parameterised. The smaller this time, the faster that 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 parameterised value, the fine tuning phase (2) in which
the Step time for fine tuning (T2) slowly approaches the setpoint value.
The increment (Y2) can also be parameterised. To reach the setpoint faster
or slower. This increment only is valid until a determined interval to the
setpoint value. This interval can be set via the parameter Control deviation
for high increments (max. control step).
Phase (3) is adjustable with an additional parameter in which light control is
suspended. A range around the setpoint value where there is no light control
must be parameterised. Only when the actual brightness is again larger than
this difference will the light control recommence. In this way continuous
control with the respective changes in brightness is avoided. This generates
smoother and less abrupt response and considerably reduces the bus load
with a master/slave control.
Phase
(3)
Phase
Y2
(2)
Y1
Phase
(1)
T2
Time
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