The Backbone of KNX: Why ETS Ensures Lifelong Smart Home Reliability
KNX is a global standard for controlling lighting, heating, air conditioning, shading and more. There are 10s of thousands of different devices in the KNX catalogue made by hundreds of different manufacturers but they all need to speak to each other but how? ETS (Engineering Tool Software) is the answer.
What is ETS?
ETS is the official KNX engineering software which allows you to assign, configure and communicate to all of the KNX devices in a project. This software is the central platform where all KNX compatible devices regardless of manufacture are programmed and commissioned into the system.
Why is ETS important?
KNX is a standardised protocol and ETS is the only official software for programming and commissioning KNX devices. Without ETS it would be extremely difficult to get a number of different devices all from different manufacturers all speaking together.
ETS partners well with the extreme flexibility that KNX provides allowing you to program buildings of any size from a 1 bedroom flat to airports. You can constantly change the project through time adding new devices and logic to an already deployed system without having to start anew. One of KNX’s big strengths is the future proofing of all devices and software. You could walk into a 30 year old existing installation and still program the system the exact same way you would program a 3 day old installation. With KNX you are not only buying into a powerful and reliable system, you are also buying into that the system will be able to be maintained forever with the future proof backward compatibility that KNX has to offer.
ETS has a number of great features on top of being the central control platform for KNX devices. KNX Secure is a hugely important feature in ETS, it locks each individual device down to it’s on secure protocol so every device can be set to an encrypted password which stops any potential threat of hacking. ETS also has a number of monitoring tools including group and bus monitor which allows for quick and easy troubleshooting if an issue arises.
How is ETS used?
Programming a KNX system via ETS is a fairly structured process so you follow the same steps more or less for each project. Obviously every project is different but you still follow the same first steps in every project and then once these steps have been completed this is where the individuality of each project is seen with building structure, layout of group addresses and parameter configuration all being different per project. Here is a simple step by step example of how an ETS file for a project is typically started:
- Create the project – This is where the file is started in the ETS software. This first step is where you create the file and name it correspondently to the project name.
- Building creation – The next step is creating the building for all of the devices to exist in. You create a building, add the corresponding floors and rooms of the project as to your site plans.
- Topology – In a KNX system you can have a number of KNX lines in one system. A KNX line is the single run of KNX and the corresponding devices on that line. On many projects there are multiple lines, for example one line for the ground floor, one line for the second floor etc. These lines are then connected by line couplers and you then have to align your topology to this. If the topology is setup incorrectly and you have device physically on one line and in the ETS on another this can cause a number of issues. So making sure you have setup you topology correctly is a crucial step.
- Parameter configuration – Each KNX device has a number of different parameters that are nearly all customisable. Many devices can carry out a number of different tasks so it is important you make sure these are setup correctly for the job you intend it to do. A few examples of different parameters in devices are scene configuration, dimming curves, HVAC setpoints and logic functions.
- Group Addresses – This is typically the longest step in the process. Group addresses are the individual lines of code that carry out a tasks. For example in lighting, to switch on/off one circuit of lighting that is one group address, to view the on/off feedback of that circuit is another group address, to dim that one circuit is another group address, to control the brightness value of the circuit is another address, and to view the brightness value of the circuit is another address. Just in that example you need five group addresses to control just one circuit of lighting, many projects contain hundreds of circuits of lighting. All multiplied by 5 these group addresses quickly add up, and that is just using a simple dimming circuit of lighting. For thermostat wall switches which control heating, AC and lighting there could be 50 addresses in just one device. This may be the longest step just due to the sheer amount of the thousands of addresses but without it the system would simply not work.
- Downloading and commissioning – This step is done when you have your device with all of the correct parameters and associated group addresses linked into it. When a device is brought into ETS a physical address is assigned to it so your interface knows which device to speak to, much like a device on your Wi-Fi network getting an IP address. You can either leave the physical address of the device as the one that was assigned to it or you can set these yourself in the topology if you are working towards a set schedule. The first download is always a full download, this includes physically pressing the programming button on said device and this sets the device to that physical address in the system and then downloads all of your parameter changes and linked group addresses to the device in one go. After this download has taken place you can then download the device via part or application download. You do not need to physically press anything on the device as it already knows its set physical address as does the system. You then have to carry out this download process on every device in the KNX project.
- Testing – Once you have taken all of the previous steps and every device is live and configured you can carry out testing. This is where you can test the devices physically with the devices manual buttons, test using the wall switches, test via the app if there is a visualisation for the project, or test from the ETS software itself.
Summary
ETS is the backbone of every KNX installation. It’s not just a piece of software that programs devices, it is the platform that brings the project together and to life. The smooth integration, formative design and robust automation of ETS ensures that KNX is the one of the most reliable and powerful solutions in the world of the smart building industry. Whether you’re designing your dream home or building a train station, ETS is the tool for deploying and getting the best out of a KNX system.
Frequently Asked Questions About How ETS Controls KNX Devices
Yes you can but there are some things to consider. To become a certified KNX programmer you need to take a week long course to gain the qualification and even then it takes some time to get used to the layout and feel for ETS. You can do it without the training course but we would strongly advise not to do this as ETS is vast and there is so much to learn. If you are taking over your own completed KNX system with no training and using ETS you could cause major issues in your property so we would advise against this. However we have had a few clients over the years who have completed the training and are currently and have been for many years maintaining their own KNX system to great success.
As professional grade software, ETS is an incredibly reliable. The software is trusted with mission critical buildings worldwide like Heathrow Terminal 5 and the Tottenham Hotspur Stadium. Each project has its own file that are robust and portable and include backup and restore functionality, which along with KNX Secure make these files bulletproof. Every single KNX device is made to be compatible with ETS so there is no worries of not being able to speak to a certain device because every single one is made to be controlled by ETS.
The time it takes to program a KNX system via ETS is completely dependent on the size of the project, how many devices are in the project and how expansive the level of control is. A one bedroom flat with 20 lighting circuits, 8 wall switches, 5 UFH heating zones and 2 AC units would take around 1 week to program. A huge commercial property like an office where there are hundreds and hundreds of lighting circuits, dozens of UFH and AC zones with over 100 switches and sensors would take months. So it is always dependent on the scale of the property and system itself.
ETS is developed and maintained by the KNX Association.
The first versions of ETS were originally created in the early 1990s, then in 1999 the KNX standard was officially established and it has been evolving ever since with ETS2, ETS3 all the way up to the current ETS6.
There are a few different ways that ETS can connect to KNX devices. The first and most common is a KNX IP interface, this device sits on the KNX line so it can speak to all of the devices on that line. You will need to be on the same network as the IP interface or have established a remote connection to the device. Typically this IP interface is also the brain of the app visualisation so is a vital device in a KNX system. The second way is a USB interface, this will sit on the KNX line and you will then connect your laptop which runs the ETS software with a USB cable into the USB interface which will then allow you to program devices on that system. The last option is a KNX router which is much like the IP interface as you connect to it in the same way but handles traffic between segments and works continuously.
ETS can speak to any KNX certified devices, which include switches, sensors, actuators, AC interfaces, manifold controllers and so much more.
Tom Green
Head of KNX Programming