As KNX prepares to celebrate its 20th anniversary, it is clear to see that it has come a long way. What started with a vision has now begun to revolutionise electrical installation technology because there is no other bus system which brings together so many diverse technologies under one umbrella.

The history of KNX

The first bus systems were created for connecting control and automation systems within industrial processes and engineers tried to use this technology – initially only in commercial buildings – for the purpose of building services installation.

Ideas for a building bus system also came from France with Batibus (HLK) entering the market. This prompted Siemens to seize the initiative for a ‘bus standard’ in the 1980s. Other large corporations, as well as prominent medium sized companies were included when the founding members of the EIBA (European Installation Bus Association) came together in Brussels.

They signed foundation documents in February 1990 after thorough legal work had been completed and with the EIBA’s headquarters in Brussels and the company being registered under Belgian law, the prerequisites for an international system were in place.

Certification

It did not take very long for legal, technical and market relevant standards determining the profile of the bus to be established by various expert EIBA committees. Thereafter it was possible both to start with EIB certification of equipment and evaluate potential partners who would be allowed to carry the EIB mark on their products.

The first versions of the ‘silver bible’ and ‘gold bible’ were created to show and explain application examples and the first training centres and EIB national groups were established. After market successes in countries such as Switzerland, Germany and Austria, it became clear that it was important to establish and broaden the conditions for standardisation on national and international levels in order to underpin the success of the system.

This meant that standardisation was put on the technical agenda at EN and IEC standards authorities and, in the commercial context, the first version of the ETS software programming tool was launched. Other bus systems that were available on the market had to be integrated too.

The new name of KNX was subsequently formed, underlining the strength of the joined forces and supported by the recognition of KNX as worldwide standard ISO/IEC 14543.

What is KNX

The term Intelligent Buildings has become something of a buzz word over the last few years and they are generally regarded as those where the owners and managers have complete control over the working or living environment. This can include heating, ventilation, air conditioning and lighting as well as the operation of blinds and shutters, electrical appliances, windows, security systems, metering and many other functions. The control of these is achieved seamlessly through the use of KNX technology.

A KNX bus cable combines building services devices and systems within a building. Sensors, such as motion detectors and thermostats, send impulses over a transmission medium to so-called actuators which then activate or deactivate the lights or the heating system, for example. These sensors and actuators can be programmed and linked as desired and it is easy for occupants to manipulate the functions of the KNX system using familiar switches, the telephone or a remote computer.

As KNX covers such a diversity of applications using one standard, it means the cabling network can be much simpler. A single twisted pair cable can often suffice, with multiple elements all operating together on a single network. KNX controlled devices are generally based around the standard green KNX bus cable (twisted pair) but can be run across radio bus (wireless), ethernet (structured cabling), fibre optics, and occasionally power lines.

New functions can easily be added to the KNX system when the needs of the occupants change or extra functionality is required or the building finds another use. KNX gateways have also been developed so that it can be linked to other control protocols, such as DALI. These simple devices are used to expand the capability of KNX and provide the complete solution for a building. KNX has also worked closely with management-level protocols such as BACnet to enable a close cooperation between these standards when a project requires additional integration.

KNX today

The new KNX Association started with more than 10,000 ETS3 licences sold in over 50 countries, over 100 training centres in more than 20 countries, 40 associated research establishments and more than 10,000 active KNX partners in nearly 60 countries around the world. This solid base was strengthened even further by more than 4,000 certified KNX products that were compatible with each other, and more than 100,000 completed houses, apartments and commercial buildings worldwide.

Today there are nearly two hundred member companies, branch offices in over twenty countries, nearly 20,000 KNX partners in 101 countries and a unified standard.

The establishment of KNX has been impressive and an achievement that no other system in this field can boast. Other bus systems have come and gone but KNX is the only sustainable international system that has proven itself so impressively.

Its success has been achieved as a result not only of the rapid integration of the market players involved, but also because the system is so open. Thus, many product developments which did not emerge until more recently, could be integrated without any problem. Over time it has emerged that technologies such as audio/video, green building systems and smart metering have found their ideal platform in the KNX standard.

The future

In the last 20 years KNX has achieved a lot but according to President Iain Gordon, making it accessible and effective has been one of the main reasons for success: “Five years ago KNX was only utilised by forward thinking companies and very few people in the UK understood the benefits which the technology had to offer. Thankfully this has now changed and the people who are part of the UK Association have a much better understanding of how to grow the market.

“One of the main drivers for this change has been education and this is where I see that the majority of our success will lay in the next ten years. We need to get KNX on the electrical syllabus for apprentices because it is only by educating the young people who are entering the market that we can hope to continue to grow.”

Despite its success there is still a long way to go and although the drive towards reducing energy consumption has helped KNX to become more acknowledged in the market, Iain suggests that this is not the main reason for their recent achievements: “The legislation to reduce energy consumption has undoubtedly helped, but as with any legislation, the Government will state a target and a number of different solutions will be launched to meet it. Sadly a number of these are simply quick fix solutions and personally I think it is dangerous to just be seen to toe the line. What we need is a more robust approach and I firmly believe that is what KNX provides.

“What we have seen is a benefit from increased awareness of KNX. With reference projects such as T5 and Media City we are able to prove that the technology works and that it is a cost effective way to achieve building automation. The savings which can be gained from this technology have become more apparent but I don’t believe that this is a result of the Government legislation, it is more a result of the need to work smarter and upgrade our operating systems to use the latest technology available.”

KNX is having a growing impact on the commercial environmen
t particularly with the introduction of directives such as CRCEES in April 2010 when it will undoubtedly continue to see success with businesses looking to cut energy costs. But I think the main point is that over the last few years KNX has simply grown up – no longer the little brother of the building automation world, KNX has finally found its feet and I think we can expect to see many more exciting developments over the next 20 years.