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KNX Partnersby New Forest Technology Services
1/0/0What is KNX

What is KNX? The open standard that lets a building think as one.

KNX is an open, international standard for home and building control. It lets lighting, heating, cooling, blinds, security, energy and AV equipment from hundreds of manufacturers talk to each other over one network, so a building behaves like one joined-up system instead of a collection of separate gadgets.

Open standard

ISO/IEC 14543-3 and EN 50090

Any brand

500+ certified manufacturers

Built to last

30+ years of compatibility

1/1/0What is KNX

A protocol, not a product.

KNX is a communication protocol: a shared language that devices in a building use to talk to each other. Nobody owns it, and nobody sells “a KNX”. Manufacturers build switches, sensors, dimmers, thermostats and touchscreens that speak it, and every one of them is certified to work with all the others.

That’s the whole point. You choose products for how they look and what they do, not for which logo they need to match. And because it’s an approved international standard, the building you wire today will still speak the same language in thirty years.

Published as a standard in

  • ISO/IEC 14543-3International
  • EN 50090European · CENELEC
  • EN 13321-1European · CEN
  • ANSI/ASHRAE 135United States
  • GB/T 20965China
Maintained by KNX Association at knx.org

You don’t buy “a Wi-Fi”.

You buy a laptop, a phone and a printer from whoever you like, and they all join the same network.

You don’t buy “a Bluetooth”.

Headphones, speakers and cars from different makers pair up because they speak the same language.

You don’t buy “a KNX”.

You choose switches, sensors, dimmers and touchscreens from any certified maker, and they all understand each other.

Certified to work together

Every product is tested against the standard before it can carry the KNX mark, so a keypad from one maker can drive a dimmer from another.

One tool for every brand

ETS, the software from KNX Association, programmes every certified device from every manufacturer. No proprietary tools, no locked boxes.

Run by an association, not a company

KNX Association in Brussels looks after the standard, certification and training. No single manufacturer can change the rules or switch it off.

Backward compatible

Devices from the original European Installation Bus of the early 1990s still work alongside products released this year.

1/2/0How it travels

One language, four ways to carry it.

Most KNX runs on a dedicated green cable. The other media exist for the places a cable can’t reach, and they all mix happily in one installation.

ETS6

One tool programmes the lot

ETS is the manufacturer-independent software from KNX Association. Every certified product, from every maker, is set up in the same place.

Most installs

KNX TP

Twisted pair

The famous green bus cable, laid alongside the electrics at first fix. The most common and most reliable way to run KNX.

Backbone

KNX IP

KNX IP

KNX over Ethernet. A fast backbone between floors and buildings, and the link to apps, touchscreens and remote access.

Retrofit

KNX RF

KNX RF

Wireless KNX for retrofit, where a cable simply can’t go. Mixes seamlessly with a wired system.

Specialist

KNX PL

Powerline

KNX over the existing mains wiring. Rarely used today, but still part of the standard.

1/3/0How KNX works

Sensors, a bus and actuators. That’s the whole idea.

There’s no central box running the show. Every KNX device has its own small processor, and they cooperate by sending short messages to each other. Here’s what happens when someone presses a light switch.

  1. 01

    Sensors say what’s happening

    A wall keypad is pressed, a presence detector sees someone, a weather station feels the wind pick up. Each sensor turns that event into a short message, called a telegram.

  2. 02

    The bus carries the message

    Telegrams travel along the KNX bus: usually a green, low-voltage (around 30 V DC) twisted-pair cable laid next to the mains wiring. Every device on the line hears every message.

  3. 03

    Group addresses decide who listens

    Each telegram is sent to a group address such as 1/1/1 (“hall lights”). Any device programmed to listen to that address reacts; the rest ignore it. One press can drive one light or fifty.

  4. 04

    Actuators do the work

    Dimmers, relays, blind and valve actuators receive the telegram and switch, dim, move or open. Many also report back, so the keypad LED, app and touchscreen always show the true state.

How a KNX installation is organised

KNX scales the same way from a flat to an airport: devices sit on lines, lines join into areas, and everything is designed and programmed in ETS, the manufacturer-independent software from KNX Association.

Line
The basic segment of bus cable, with its own power supply. A standard line takes up to 64 devices.
Area
Lines join into areas through couplers, and areas join into the backbone, so one installation can grow to tens of thousands of devices.
Physical address
Every device has a unique address in the form area.line.device, such as 1.1.12, so it can be found and programmed.
Group address
The functional link between devices, written main/middle/sub, such as 2/1/4 for “lounge heating”. This is what an installer designs.
2/1/0Why KNX

Why every building should have KNX as its backbone.

Think of KNX as the building’s nervous system. Lights, heating, blinds and sensors are the muscles and senses. Apps, touchscreens and voice are simply ways of talking to it. Get the nervous system right and everything else can change around it, for decades.

How you control it · changes whenever you like

  • Wall keypads
  • Touchscreens
  • Phone app
  • Voice
  • Control4
  • Loxone
  • Sensors & schedules

The backbone · stays put

KNX

One cable · one language · decades of life

What it runs

  • Lighting
  • Heating & cooling
  • Blinds & shading
  • Security & access
  • Energy & EV
  • AV & audio

No single point of failure

Every KNX device has its own intelligence. There’s no central box that takes the whole building down when it fails.

Works with no internet

Core functions run locally on the bus. No cloud, no subscription, and no server somebody else can switch off.

Outlives the apps

Apps, hubs and platforms come and go. The cable in the wall, and the standard it speaks, stay put.

Never locked to one brand

Pick the switch designs you love from any certified maker, and change your mind later without rewiring.

Saves energy by design

Presence-led lighting and heating, shading that follows the sun, and metering that shows where the energy goes.

Secure when it matters

KNX Secure adds encryption and authentication on the bus and over IP, for homes and commercial sites alike.

Grows without starting again

One flat or a whole campus: same standard, same software, and you can extend it years later.

Anyone certified can take over

Over 140,000 KNX professionals worldwide use the same tools, so you’re never tied to a single installer.

First fix is the moment.

Laying a KNX cable while the walls are open costs far less than retrofitting later. It’s the single decision that future-proofs a building, even if you only automate a few things on day one.

Plan it in now
2/2/0How it compares

Built to last, not to be replaced.

Plug-in smart gadgets are great for a rented flat. For a building you own and want to keep working, the backbone matters. Here’s the honest difference.

  • Who owns it?
    KNX: Nobody. It’s an international standard
    Plug-in gadgets: One manufacturer
  • Mix and match brands
    KNX: 500+ manufacturers, certified to work together
    Plug-in gadgets: Usually one ecosystem
  • Works without the internet
    KNX: Yes, everything core runs locally
    Plug-in gadgets: Often relies on the cloud
  • If the maker drops support
    KNX: Other certified products drop straight in
    Plug-in gadgets: Devices can stop working
  • Reliability
    KNX: Dedicated wired bus
    Plug-in gadgets: Wi-Fi and batteries
  • Designed lifespan
    KNX: Decades
    Plug-in gadgets: A few years
  • Someone else can take it over
    KNX: Any certified KNX professional
    Plug-in gadgets: Depends on the app
  • Scale
    KNX: One room to an airport
    Plug-in gadgets: Rooms and small homes

And it doesn’t compete with Control4 or Loxone. We’re partners for both, and they sit beautifully on top of a KNX backbone: KNX does the wiring and the devices, the control system does the experience.

1/4/0A short history

Over thirty years of one language.

  1. 1990

    The European Installation Bus (EIB) arrives, created by leading European electrical manufacturers to replace a tangle of separate control wiring.

  2. 1999

    EIB, BatiBUS and EHS merge, KNX Association is founded in Brussels, and the three become one standard: KNX.

  3. 2003

    KNX is approved as the European standard for home and building electronic systems, EN 50090.

  4. 2006

    KNX becomes an international standard, ISO/IEC 14543-3, covering twisted pair, powerline, radio and IP.

  5. Today

    More than 500 manufacturers, 8,000+ certified products and a worldwide community of certified professionals, with devices from the EIB era still working alongside new ones.

knx.org

Go to the source

KNX is looked after by KNX Association, an independent body in Brussels. Their site is the official reference for the standard, certified products and training.

Want KNX in your building?

We’re a certified KNX Partner in Lymington, designing, programming and installing KNX across Hampshire, Dorset and beyond.

Talk to us