Chapter 1 · Understanding Lighting
Choosing the Lighting Technology
There is more than one way to control a light, and the choice decides how smoothly it dims, how much space it takes in the cabinet, how expensive the wiring is, and whether the customer ever hears a buzz.
Pick the wrong technology for a room and no amount of good programming will fix it.
By the end of this lesson you will be able to:
- Name the main ways of controlling lights and the trade off each one carries
- Explain why low voltage DC dimming has become the standard for modern buildings
- Decide which technology suits a given lighting job
The situation
You are planning the lighting for a house. The living room wants warm, dimmable, color adjustable light. There is a run of indirect LED strip above the kitchen units. The garage needs a light that simply comes on and off. And the owner wants to reuse a few existing mains voltage fittings in the hallway.
That is four different lighting jobs in one project, and they do not all want the same technology.
DC dimming, and why it has become the default
Low voltage dimming at 12 or 24 V has become increasingly popular, and for good reason. Unlike high voltage dimming, it allows extremely smooth dimming with no disruptive flickering, no buzzing and no other noises. Thanks to PWM technology, virtually any 12 V or 24 V LED light can be dimmed.
Its advantages are easy to summarize: very smooth brightness control, great variability, an excellent price to performance ratio, and safe low voltage.
The tools
The main tool is the RGBW 24V Dimmer, which does PWM control of LED lights and is ideal for dimming LED strips for indirect lighting. It supports RGBW, Tunable White and single color dimming, has four channels at up to 50 W each, and comes in Tree and Air versions, on a DIN rail or in a compact form that fits inside furniture.
Other options exist for particular cases. The Nano Motor Controller is designed mainly for DC motors, but its configurable outputs also allow continuous dimming of LED lighting, with one PWM channel up to 50 W.
The DMX Extension can dim LED fittings using the DMX protocol, though DMX is now considered outdated technology, with dimming that is not smooth and a need for DMX knowledge.
Tree version
Air Version
one PWM channel up to 50 W
Why mains voltage dimming causes problems
High voltage dimming only allows brightness control, with no color control. It was the best method for dimming incandescent bulbs, but today's LED lights bring several complications:
- Not all LED lights are dimmable
- Those that are do not always dim smoothly
- Flickering often occurs at low brightness, which rules them out for night mode
- Buzzing or humming can frequently be heard
- Color temperature can be inconsistent, since bulbs from different production batches vary
In today's world, high voltage dimming is declining and is gradually being replaced by low voltage dimming.
When mains dimming is still the answer
It has its uses. Its advantages are brightness control without inrush currents, and the sheer number of light fittings available on the market. So it remains the answer when existing 230 V fittings must be reused, typically in a renovation.
The Dimmer Extension handles four dimming channels with eight digital inputs. The Nano Dimmer Air is a single channel compact module designed primarily for renovations, fitting into a circular 68 mm outlet box.
Switched lighting
Switching lights on and off is the least effective way to control lighting. It does not allow the intensity to be adjusted, so designing an effective lighting layout needs the expertise of a lighting architect.
There is a further complication. Modern LED lights often have high inrush currents that can damage relay contacts, so extra protection is needed. All of this makes the solution more expensive, more complicated and less efficient than it first appears.
DALI
DALI is a widely used standard protocol in the lighting industry, with many manufacturers offering light sources and dimmers that work with it. If a project specifically requires DALI fittings, LOXONE integrates them over Link and Air.
There are things to keep in mind when planning. Many DALI lights do not dim as smoothly as LOXONE light sources. Obtaining matching replacement luminaires from various manufacturers can become difficult over time. And since 240 V ballasts are commonly used with DALI, expect a significant standby power consumption for the same number of luminaires.
The DALI Extension comes in versions for 64 or 10 devices, both supporting up to 16 light groups and DALI-2 certification. DALI Air offers a wireless DALI interface for up to 10 lights and 16 groups, which suits renovations.
10 Devices
64 Devices
10 DALI Devices
| Method | Dimming | Wiring | Cabinet Space | Best for |
|---|---|---|---|---|
| 24V DC | Smooth, color and white | Tree, inexpensive | None | The default for modern buildings |
| Switched | None | Star, expensive | Larger | Lights that never need dimming |
| Mains dimming | Fitting dependent | Star, expensive | Larger | Reusing existing 230V fittings |
| DALI | Varies by fitting | Flexible | Small or none | Projects requiring DALI fittings |
Third party lights that work with LOXONE
LOXONE has developed products together with industry partners that integrate fully into a project, carrying the Works with LOXONE seal. These include fittings from Molto Luce, XAL and Wever & Ducré.
Where a project calls for a specific architectural fitting, this is often the way to keep the design the customer wants without giving up integration.