The simplest dimming protocol still in wide use. A pair of wires carries a voltage, the driver reads it, and the whole zone follows. Nothing is addressed, nothing reports back, and for a great many rooms that is entirely sufficient.
The driver is fed mains as normal. Alongside it runs a separate low-voltage control pair carrying a DC level between roughly 0 and 10 volts.
Ten volts means full output. Around one volt means minimum. The driver reads that voltage continuously and sets its output to match — there is no protocol, no packet and no negotiation, which is exactly why it is so robust.
Every driver wired to the same control pair sees the same voltage, so they all dim together. That is the defining property of 0-10V, and both its strength and its ceiling: a zone is defined by the wiring, permanently.
A related variant, 1-10V, sets one volt as the minimum level and cannot switch the load off — it needs a separate relay to do that. Check which one a driver expects.
0-10V drivers are easy to buy and easy to wire. The part people underestimate is that the control system has to be able to produce that voltage.
Most residential wireless systems are phase-cut only. Lutron RadioRA 3 handles 0-10V through a dedicated dimming module, one per zone. Caséta does not do it natively at all.
Where a per-zone module is not the right answer, we drive Shelly 0-10V dimmer modules from our own controller. It reads the Lutron Smart Bridge PRO over LEAP — Lutron’s local, certificate-authenticated API — so a Caséta keypad or Pico remote sets the level on a 0-10V driver directly, with no cloud and no smart-home hub in the path. Home Assistant can be added for app, voice and sensors, but is not required.
Specify the PRO bridge: Caséta exposes LEAP on the Smart Bridge PRO (L-BDGPRO2), not the standard Smart Bridge; on RadioRA 3 it is the RR-PROC3 processor.
It is a substantially cheaper path to the same result, with the caveat that bridged control suits scene recall and set-level better than live hold-to-dim ramps. The same controller handles DALI drivers on the same job, so a scheme can mix both protocols without mixing control systems.
It usually comes down to how likely the zoning is to change, and whether anyone will ever want colour tuning. Twenty minutes on a call is normally enough to settle it.