Dimming Protocols Compared
0-10V, DALI, Triac, PWM and DMX selection guide.
1. Why it matters
Choosing a dimming protocol early prevents the most common lighting-controls failure: fixtures and controllers that physically connect but never dim smoothly, flicker at the bottom end, or cannot be addressed individually. The protocol decides wiring, cost per point, dimming range, and whether you can reconfigure the space later in software instead of with a screwdriver.
2. The mainstream protocols compared
| Protocol | Control granularity | Wiring | Best for |
|---|---|---|---|
| 0-10V / 1-10V | Group (broadcast) | Extra 2-wire low-voltage | Simple offices, warehouses |
| DALI / DALI-2 | Per-fixture, addressable + feedback | 2-wire digital bus | Flexible commercial, reconfig |
| PWM | Driver-level, wide range | Signal to driver | Deep dim, colour/tunable |
| TRIAC (phase-cut) | Group, legacy switches | Mains, existing dimmers | Retrofit residential/light comm. |
| Wireless (BLE/Zigbee) | Per-fixture, app/scene | None (RF) | Retrofit without rewiring |
3. Match protocol to the project
The right choice follows the building, not the brochure. Use the cheapest protocol that meets the control need, and reserve DALI for spaces that genuinely change.
- Open-plan office, fixed layout: 0-10V by zone is cheapest and adequate.
- Space that gets re-partitioned, needs per-desk control or energy reporting: DALI-2.
- Tunable-white or colour: PWM or DALI DT8.
- Retrofit where new wiring is impossible: wireless BLE/Zigbee mesh.
4. Verify dimming quality, not just compatibility
"Compatible" only means the fixture accepts the signal; it says nothing about how it dims. Insist on the tested minimum dim level (e.g. dims smoothly to 1% or 0.1%, not "10% then off"), confirm flicker-free operation across the range (percent flicker / flicker index, important for camera and health), and — critically — verify the specific driver-plus-controller pair, because the same protocol can behave differently across brands. Request a paired demo or a compatibility list from the driver maker.
5. Checklist
- Choose the cheapest protocol that meets the control need
- Use DALI-2 only where per-fixture control or reconfig is real
- Verify tested minimum dim level (1% / 0.1%), not "dims"
- Confirm flicker-free across the range (percent flicker)
- Validate the exact driver + controller pair together