0–10V, DALI and other lighting control system protocols compared

What is a protocol?

A protocol is a language that devices in a system use to communicate and share data. Lighting control systems can’t function without one.

0–10V and 1–10V dimming

What you would use it for

Dimming LED or fluorescent lights.

How it works


A 0–10V dimming driver sends a low DC voltage signal to the fluorescent ballast or LED driver. The lighting changes as the voltage is varied.

So, at zero volts the light will dim to 0% and turn off. At 10 volts the system is operating at 100% and the light will be fully on.


It works in a similar fashion to 0-10v dimming, but the voltage is ‘sinked’ by the driver and will only go as low as 10% before the power to the circuit needs to be physically switched off. This method provides a very smooth dimming curve which is especially useful for colour changing LEDs.

What you should know

  • 0–10V and 1–10V are:
    • analogue—the lighting changes according to controlled variations in voltage
    • hardwired—each device needs its own wiring, which makes installation quite tricky if the lighting control system is large and complex
    • unidirectional—data goes only one way, from the dimming driver to the LED driver or fluorescent ballast. Because there’s no signal coming back from the lights, there’s no data on which to measure their performance, as with digital systems
  • A 0–10V system can accommodate around 10 luminaires per controller.

DALI (digital addressable lighting interface)

What you would use it for

Lighting control for LED, fluorescent, halogen or incandescent lights.

How it works

A DALI ballast receives voltage through one pair of wires, while another pair relays a digital signal from the controller devices (e.g. a dimmer) to the luminaires.

In a DALI network, each ballast and relay switch is assigned a unique address to which commands can be sent. This allows the system to be controlled from web-based software installed on a PC.

What you should know

  • DALI is:
    • digital—meaning the system can dim lights to much more precise levels of brightness
    • bidirectional—the two-way communication between the DALI ballast and luminaires means the system can diagnose issues and relay feedback and data to the user interface (i.e. PC software)
    • open—because it isn’t a proprietary technology, it’s available from many different suppliers worldwide and can be used alongside devices from other manufacturers
  • The DALI protocol is useful if luminaires need to respond to more than one input device (such as a wall switch and a daylight sensor).
  • As with 0–10V dimming, DALI requires a lighting control cable, but the cable can be run between many fittings. In fact, one DALI network can accommodate up to 64 DALI ballasts.
  • DALI allows lighting controls to operate as stand-alone systems or be integrated into larger building management systems.

DSI (digital serial interface)

What you would use it for

Dimming LED, fluorescent, halogen or incandescent lights.

How it works

Like 0–10V dimming, DSI enables hard-wired groups of luminaires to dim collectively. But where 0–10V uses a varying voltage to tell the lights how to dim (the amount of current is roughly equal to the intensity of the light—e.g. 1V = 10%, 5V = 50% and so on), a DSI driver sends digital data to define precise levels of brightness.

Although DSI ballasts can lower the light level to ‘zero’, the light is still drawing current and so, technically speaking, isn’t switched off.

What you should know

  • DSI is:
    • incompatible with DALI, despite being its predecessor
    • proprietary to one brand (Tridonic), and so can only be used with devices made by that manufacturer

Other protocols


An open standard for wireless technology which uses digital radio signals for lighting and other building automation.

An alternative to Bluetooth, it uses the IEEE 802.15.4 wireless standard for wireless personal area networks (WPANs) and operates on 2.4 GHz, 900 MHz and 868 MHz frequencies. These frequencies can be very congested, however, which can interfere with signals or cause them to drop.


A digital control protocol used in building automation. As well as enabling networked lighting systems, it can also be used for home entertainment systems, energy management and security alarms.


A digital protocol used to control theatrical stage lighting. The DMX signal is generated by a lighting control system and requires dedicated cabling between the controller and driver.

Wired vs. wireless lighting control—what’s the difference?



All devices are hardwired to the building’s electrical system

Only the central processor is hardwired to the building’s electrical system

Devices physically connected by low-voltage wiring

Devices are wireless and battery-powered and communicate over radio frequencies

Centralised to one location, such as a lighting control module or lighting control panel

Devices have their own controllers and receive commands via a central processor


Reliable, as there is no signal interference

Easy to install, which means:

  • less disruption
  • reduced labour costs
  • fast turnaround for refurbishment projects

Mains-powered, so no need to replace batteries

Designed to be user-friendly

Ideal for new-build premises

Simple to add more devices

Perfect for situations where it’s impossible or impracticable to run cables, such as in listed or historic buildings

Related content

A guide to Audacy, CMD’S wireless lighting control system

Download our Audacy brochure

Audacy FAQs