DALI, KNX, Casambi or Lutron? Choosing Lighting Controls for a Fit-Out

The choice of lighting control changes the cabling. Switched circuits, DALI, KNX, Casambi and Lutron are each wired differently, so the choice belongs on the first electrical drawing rather than being settled on site.

This is what each system means for the electrical contractor, and where the cost and the late changes come from. It is written for designers specifying a commercial fit-out in Singapore.

The five options at a glance

What actually travels down the wire

The same "dim to 30%" means something different on each system. A switch can only break the supply. A phase-cut dimmer chops each half-cycle of the mains. A 0–10 V driver follows a DC level on a separate pair. DALI sends a digital frame with an address and a level, and Casambi relays a radio command from fitting to fitting. Drag the command and watch each one.

DALI: a control pair to every fitting

DALI is the open standard IEC 62386. One two-wire pair carries both the control signal and the bus power. Apart from the bus power supply’s own terminals, the connections are not polarity-sensitive, and the pair can be run as a bus, a star, a tree or a mix of these, though not as a closed ring or a mesh. A line takes up to 64 drivers, plus 64 sensors and switches on DALI-2, with 16 groups and 16 scenes, and the cabling is limited to 300 metres on 1.5 mm² cable.

DALI runs at a low voltage, typically about 16 V, but it is not SELV: nothing guarantees its separation from the mains. So it is treated as mains wiring, which means it can share a sheath with the mains, for example in five-core cable, as long as everything on the circuit is rated for mains voltage.

• ›Every fitting needs a DALI driver, so the fitting schedule has to say DALI before the fittings are ordered.
• ›First fix is the DALI pair to every fitting, plus bus power supplies, controllers and sensors.
• ›Addressing and commissioning take real time on site, and more of it on a large floor with many sensors.

MeetingPresentationDaylightEvening

Illustration

Meeting. Everything at full; the timber-wall spots at 80%.

Relight it yourself Show the DALI groups

• 1Downlights by the screen100%
• 2Downlights, window row100%
• 3Downlights, wall row100%
• 4Linear pendant over the table100%
• 5Track spots on the timber wall80%

An illustration, not a BSH project: a Blender render lit with the fittings’ measured IES files, recombined live at your levels. Real light levels come from a lighting calculation.

KNX: a building bus, and actuators in the board

KNX is standardised as ISO/IEC 14543-3 and EN 50090. It runs on a 30 V bus in green two-pair cable, kept apart from mains conductors. One line can have about 1,000 metres of cable and around 64 devices on a standard power supply.

• ›The lighting is switched and dimmed by DIN-rail actuators, which take space in the distribution board. Allow for it when the board is sized.
• ›Bus cable goes to every keypad and sensor, so keypad positions need to be fixed before the walls close.
• ›KNX is programmed by a specialist integrator. We install and wire it, and work with the integrator on the programme.

Casambi: no control cable between devices

Casambi runs its own mesh network, Casambi Mesh, over Bluetooth Low Energy, built into drivers, luminaires, switches and sensors. Each device carries the control logic, so there is no central controller to fail, and the phone app is both the user interface and the commissioning tool. A network takes up to 250 devices, and DALI lines can be brought in through a gateway.

• ›There is no control cable between devices, which suits heritage buildings, refurbishments and late changes.
• ›Drivers, luminaires and mains-powered sensors still need a supply; switches can be wireless, including self-powered EnOcean switches. The per-device radio modules replace some of the cable cost rather than all of it.
• ›Walls, metal ceilings and distance affect radio, so large or dense floors need planning for range.

Lutron: wired, wireless or both

Lutron makes several systems rather than one. Quantum is wired, on Lutron’s own control link. Athena can be wired or wireless and works with Lutron’s own drivers as well as DALI and 0–10 V modules. Vive is wireless, and Lutron describes it as having no control wire to pull.

• ›Which Lutron system is specified decides whether there is control cabling at all.
• ›The components are Lutron’s own and the system is commissioned by Lutron or its partners, so the programme needs their commissioning dates.
• ›Wireless modules have a stated radio range, so the positions of modules and keypads matter.

The late changes that cost the most

• ›Changing to DALI or dimming after the drivers are bought. Every driver has to be a DALI or dimmable type, so the drivers are replaced.
• ›Re-zoning after the cable is pulled. Regrouping is only software if every fitting is already on the bus; moved fittings or a redesigned corridor mean the cabling is redone.
• ›Adding sensors or keypads after the ceiling closes. On DALI or KNX that means extending the bus through a finished ceiling; on a wireless system, a new device and a check of its range.

Where we come in

We have installed DALI, KNX and Lutron lighting-control systems in office fit-outs for the design firms that specify them, and in 2026 Casambi wireless control for a corporate office’s multi-purpose hall and two boardrooms, installed, commissioned and handed over with our Casambi integration partner. We price the controls from your drawings, wire them to the manufacturer’s requirements, and work alongside the integrator who programmes them.