VIAVAI, connected directly to the 40205/40210 power supply [not dimmable at 48V constant voltage], allows the lights to be controlled in ON-OFF mode only.
The use of DALI 40211/40212 power supplies allows the control of MINI/ZOOM/BOB light sources “ONE BY ONE”, independently of each other or all together [MINI/ZOOM/BOB in 0-10V version].
In the DALI connection, the optocoupler is used to convert a BUS DATA signal into a BUS DATA SELV signal.