Choosing between DALI-2 and 0–10V is a system architecture decision, not a dimming-feature checkbox. Both can dim industrial LED high bays, but they differ in addressing, feedback, wiring, commissioning and the way future changes are handled.
Short answer: choose 0–10V for simple, stable zones where low first cost matters. Choose DALI-2 when individual addressing, re-zoning, emergency integration or device-level data justifies additional design and commissioning.
How the two systems differ
0–10V uses an analog control signal. Luminaires connected to the same control pair generally respond as a group. DALI-2 uses a digital bus, allowing devices to be addressed and grouped in software within system limits.
| Procurement issue | 0–10V | DALI-2 |
|---|---|---|
| Typical zoning | Physical control wiring | Software addressing and groups |
| Feedback | Usually none | Device status and supported diagnostics |
| Reconfiguration | May require rewiring | Often changed in commissioning software |
| Interoperability proof | Driver/controller compatibility test | Verify DALI-2 certified components |
| Best fit | Simple retrofit or fixed zones | Large, changeable or integrated facilities |
DALI-2 certification is based on IEC 62386-related test specifications and independently verified results. The DALI Alliance maintains a public product database; a claimed product that does not appear there is not DALI-2 certified (certification overview).
Map control zones before choosing a protocol
Start with operational zones: rack aisles, picking stations, docks, circulation routes, maintenance areas and daylight perimeter. Then document who needs to change them and how often. A warehouse whose racks move every quarter values software regrouping differently from a fixed workshop.
For 0–10V, count control pairs, relays and zones. Define whether the system sinks or sources current, how the driver behaves if control wires are open or shorted, and whether mains isolation is required by local code. For DALI-2, define bus power, application controllers, addressing responsibility and the handover file.
Specify sensor behavior, not just “motion sensor”
Write a sequence of operations for every space:
- occupied output level;
- unoccupied standby level or off state;
- hold time and fade time;
- daylight target and deadband;
- after-hours override;
- failure state if the sensor or bus becomes unavailable.
DALI-2 input devices can implement Part 303 for occupancy sensing and Part 304 for light sensing. Combination sensors may contain both functions (DALI Alliance sensor guidance). Check the exact certified component, not only the logo on a luminaire brochure.
Do not overlook driver dimming quality
Two drivers labeled “0–10V” or “DALI-2” may behave differently at low output. Request the dimming range, minimum stable level, default power-on level, standby consumption and flicker performance at 100%, 50%, 20% and minimum output. Test the proposed sensor, controller and driver together before production.
This matters in warehouses that hold lights at a low background level. An unstable driver at 10% can create visible modulation or inconsistent output even when its full-power data is acceptable.
Compare lifecycle cost
Include design, bus power supplies, gateways, control cable, commissioning labor, software licenses, training and replacement-device availability. DALI-2 may reduce rewiring when layouts change, but a poorly documented system can become expensive to maintain. 0–10V may be economical initially, but adding zones later can require new cabling.
Request an editable as-built package containing addresses, groups, scenes, sensor settings, firmware versions and administrator credentials. Procurement should state who owns the configuration data.
RFQ clause you can adapt
“The supplier shall provide dimmable luminaires, control devices and drivers tested as a complete system. Submit wiring diagrams, device schedules, certification identifiers, standby power, dimming curves and a written sequence of operations. Commissioning shall include addressing, group/scene setup, sensor calibration, functional testing and an editable as-built backup.”
If DALI-2 is required, verify components in the official DALI product database. If 0–10V is chosen, require a compatibility sample because the label alone does not guarantee identical low-end behavior.
A practical selection rule
Use 0–10V when zones are few, physical wiring is accessible and facilities staff want familiar controls. Use DALI-2 when the project needs individual addressing, frequent reconfiguration, centralized monitoring or multi-vendor digital interoperability. Either protocol can save energy; the outcome depends more on zoning and commissioning than on the acronym.
Before requesting pricing, combine this control brief with the industrial lighting RFQ checklist and the actual lighting layout.
