Konnex

KNX is a standardised (EN 50090, ISO/IEC 14543), OSI-based network for building automation. KNX is the successor to, and convergence of, three previous standards: the (EHS), BatiBUS, and the European Installation Bus (EIB or Instabus). The KNX standard is administered by the KNX Association.

The standard is based on the of EIB but enlarged with the physical layers, configuration modes and application experience of BatiBUS and EHS.

KNX defines several physical communication media:

KNX is designed to be independent of any particular hardware platform. A KNX Device Network can be controlled by anything from an 8-bit microcontroller to a PC, according to the needs of a particular implementation. The most common form of installation is over twisted pair medium.

KNX is approved as an open standard to:

KNX Association, as of 1 March 2014, had 339 members/manufacturers from 37 countries. Japan's Fujitsu General was enlisted as member number 300. The complete list can be found here at knx.org

The KNX Association has partnership agreements with more than 30,000 installer companies in 100 countries and more than 60 technical universities as well as over 150 training centres.

The access to the KNX specification used to be restricted, however as from January 2016 the access is free assuming you have a free account on the knx association website.

All the devices for a KNX installation are connected together by a two wire bus (the most common form of installation), thus allowing them to exchange data. The function of the individual bus devices is determined by their project planning, which can be changed and adapted at any time.

Sensors are the starting point for every action, because they gather information and send it on the bus as a data telegram. This can be information about room temperatures, movements, wind measurements or manually input instructions (Push buttons). Sensors are selected depending on the required application.

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