DALI gateway architecture: choosing how your line talks to KNX or BMS
A DALI line rarely lives in isolation — most projects connect it to KNX, a BMS or a wider building network through a gateway. This is a selection framework for integrators, not a repeat of a single vendor's commissioning steps.
Choosing a gateway pattern
Count the DALI lines in the building
A single small line often suits a point-to-point gateway; multiple lines across a building usually favour a BMS/Modbus gateway aggregating them under one head-end.
Decide where scene logic lives
Scene and group logic can run locally on the DALI line or centrally in KNX/BMS — this decision shapes which gateway pattern fits and how much logic duplication you accept.
Map DALI addresses to the upstream system
Point-to-point gateways typically map DALI groups or individual addresses one-to-one to KNX group addresses; BMS gateways report status and accept commands per DALI line.
Plan for gateway failure
Verify local DALI switches keep basic on/off and dimming functional standalone if the upstream KNX/BMS connection is lost — this is the practical test of a well-designed integration.
What separates a robust gateway integration
Local control survives a gateway outage
A well-designed gateway integration keeps basic on/off and dimming functional locally on the DALI line even if the upstream KNX/BMS gateway connection is lost.
Point-to-point mapping for single lines
For a single DALI line, mapping groups or individual addresses directly to KNX group addresses is usually the simplest, most transparent pattern.
BMS/Modbus aggregation for multiple lines
Buildings with several DALI lines often benefit from a BMS/Modbus gateway that aggregates status reporting and control under one head-end instead of one gateway per line.
Scene logic placement is a design decision
Keeping scene logic on the DALI line reduces dependence on the upstream system; centralising it in KNX/BMS gives more cross-system coordination — pick deliberately, not by default.
Standalone resilience by design
The gateway should be a convenience layer, not a single point of failure — local DALI switches and scenes should keep working even without the upstream link.
Fits the existing DALI/IEC 62386 line
Gateway integration doesn't change the underlying DALI line — addressing, groups and scenes (up to 64 devices, 16 groups, 16 scenes) stay governed by IEC 62386.
What a gateway architecture review covers
A selection framework before you commit to a pattern
- DALI line count and topology mapping
- Point-to-point vs BMS/Modbus pattern comparison
- Scene logic placement recommendation
- Gateway failure/fallback behaviour check
- Address mapping plan for the upstream system
Frequently asked questions
Point-to-point or BMS gateway — which do I need?
A single DALI line usually suits a point-to-point gateway mapping to KNX group addresses; multiple lines across a building usually favour a BMS/Modbus gateway aggregating them under one head-end.
What happens to DALI control if the gateway fails?
In a well-designed integration, basic on/off and dimming stay functional locally on the DALI line, since local DALI switches operate independently of the upstream gateway connection.
Should scene logic run on DALI or in KNX/BMS?
Either is valid — running it on the DALI line reduces dependence on the upstream system, while centralising it in KNX/BMS enables broader cross-system coordination. The choice depends on the project's redundancy requirements.
Does a gateway change how the DALI line itself is addressed?
No. The underlying DALI line keeps its own addressing, groups and scenes per IEC 62386 — the gateway only exposes those as points in the upstream system.
Is there a worked example of this kind of integration?
Yes, we also document a step-by-step KNX-DALI gateway commissioning walkthrough alongside this architecture-selection guide.
Designing a DALI-to-KNX or BMS integration?
Contact our engineers to review your gateway pattern, address mapping and failover behaviour before commissioning.