8
for 0 = off) below 126 (50% brightness, 3% luminous flux) are interpreted as
the minimal lighting level.
Together with the DALI Gateway following effect is to attend: For example
on the ECG is a dimming zone from 3…100% printed, you have an ECG
which can not drop under the minimal luminous flux of 3%. This could re-
sponse of a certain switching on of the fluorescent lamp. This minimal lumi-
nous flux of 3% corresponds with a DALI dimming value of 126 Digits. This
value is 50% of the percentage brightness. This means that a lower bright-
ness level (under 50%) is not possible. Lower brightness values will copy on
the 50% value. If a brightness value lower than 50% will set over the KNX
this will copy to the same DALI brightness. But the lamp only can switch on
the brightness value of 50%. This real lamp brightness will send back to the
KNX and visualised.
The same behaviour will happen with a dimming command. If the minimal
dimming level is reached and a dimming down command will received
again, only the minimal dimming level, in our case 50%, will send back to
the KNX.
To avoid such a limitation, suitable ballast with a dimming range of
1%...100% or 0.1%...100% have to be used.
ABB i-bus
®
KNX
Introduction
