What your ETS project already knows

Your KNX project file is a detailed description of your house, and almost nobody reads it. It lists every device, every channel and every setting. It is hard to read, because it is written in the language of the wire and not the language of the rooms. This page explains what is inside and why it is messy. It is worth asking your installer for a copy.

Ask your installer for your ETS project and you will be given a file ending in .knxproj. Most owners put it with the electrical certificates and never open it. It is seen as a wiring record, something you need when something breaks or the next contractor takes over.

That undersells it. The file is a zipped set of files describing every device, every channel, every setting and every link between them. It is often more up to date than the drawings, because it is changed when the system is changed. (If your project is protected by a password, ask for that as well.)

What is inside

Four things matter.

Channels and what they carry. 1/1/31 might be an on-or-off light. 3/2/0 might be a switch that enables a heating zone. 0/5/7 might report that someone is in a room. Each channel can have a type that says what kind of value it carries: on or off, a percentage, a temperature. Some channels have no type set, and that is common.

The devices and their settings. Which maker, which product, and how it was set up. This is how you learn that the box on channel 7 is set to a staircase light with a 3-minute timer. That explains behaviour that would otherwise look like a fault.

The links. Which connection on which device is tied to which channel, and the flags set on each one. Flags show whether a connection reports or accepts commands. They are strong clues, not proof, because they can be set wrongly.

The names. The words a person typed in: Bath 2 Towel Rail, Sitting Rm Lights ctrl. These carry the most meaning about the building. They are also the messiest.

Why it is hard to read

If everything were named in one style, this would be easy. It never is.

A house of any age has passed through several hands. The first commissioning used the maker’s defaults. A later extension used a different installer’s style. Someone renamed half of one floor during a refit and stopped halfway. Some channels belong to equipment that was removed. Some are called Spare and still do something.

This is not a criticism of installers. It is the normal wear of a lived-in building. It is why “just read the file” is easier said than done.

What one real home looks like

The reference home we describe on this site is one real KNX installation in Lindfield, NSW. Readback read its project in about a minute. It found:

• 668 group addresses
• 1,403 device settings
• 21 automatic behaviours set up inside the devices, now written out as plain sentences
• 234 unused connection points, which are typical build leftovers and not a fault

It also found four rooms where the lights could switch off on someone sitting still. The presence sensors there wait only 10 seconds after the last movement. The maker advises 30. It is a factory setting, and easy to miss in ETS.

This is one home. We do not say every home looks like it.

What you can get from it

Once the file is read room by room instead of address by address, a few things become easier to see.

What is wired but never set up. Many houses have equipment that was installed and then left alone. An example is a light sensor that reports a brightness that nothing uses. You paid for that hardware. A list of it is often useful.

Where the system cannot tell. A light with no status signal cannot confirm that a command worked. A list makes the gaps visible. “The lights sometimes don’t respond” becomes a list of specific lights.

A handover that explains itself. Settings and automations written in plain sentences, room by room, are easier for you and for the next person to follow.

Anything unclear stays a question for your installer, such as “these eleven channels look like one room, which room is it?” That is better than a 668-row spreadsheet that nobody will finish.

Why this comes first

Every useful rule is about rooms and what is in them, such as “keep this zone steady” or “do not switch everything off while a guest is in the next room”. Without a description of the rooms, each rule is written by hand, address by address, for one house. Reading the project well comes first.

Your ETS project already knows a lot about your house. It has just never been asked in a language you could read.

Next steps

Ask your installer for a copy of your project file. Then read KNX in plain English to see why the wire alone does not keep any of this, and the language of your installation to check the words used here. Installers can find fix-it notes at KNX notes.

Send this to your installer, or ask them:

• Can I have a copy of our ETS project file?
• Can you run a free Readback on our project?

For installers

Installers: run a free Readback

Want to talk it through? Book 20 minutes with Ted.