In a mixed KNX-DALI architecture, a DALI-2 presence sensor (sitting on the DALI bus) can drive only the room's DALI control gear, while a separate KNX presence sensor handles room-level commands (HVAC, blinds).
True
A common and efficient hybrid pattern dedicates one sensor per natural function: a DALI-2 presence sensor in the room drives the local control gear directly (without traversing KNX, for faster reaction), and a complementary KNX sensor drives HVAC and blinds via the building backbone. Lighting reacts within about 100 ms on DALI, while a 2 s KNX-driven HVAC reaction is acceptable. The design has to be coordinated with the lighting architect.
Make sure the room hand-over between sensors is documented — a customer service desk faced with 'why does the light come on but the blind not' wastes hours when only one of the two sensors is faulty.
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