ABB i-bus® KNX uses an additional data line to connect devices and systems, such as heating and lighting, to a networked system. If each application were designed individually – as is usual – such networking would only be possible with high costs and major technical expenditure.

The KNX structure

The KNX structure created is very flexible in its design due to the possible connection of the devices: linear, tree and star wiring configurations are allowed.

The KNX topology

The KNX topology is arranged in lines that can be interconnected via couplers depending on the size of the network. The devices in the respective lines (sensors and actuators) are supplied with energy by a power supply (30 V) whereby the entire KNX bus system can be configured with more than 50.000 bus devices.

The communication medium - the KNX cable

In simple terms, the KNX bus consists of a pair of twisted-pair wires (cable type, e.g. YCYM 2 x 2 x 0.8 or J-H(ST) H 2 x 2 x 0.8 halogen-free) that connect the KNX devices. Over this cable, data telegrams are transmitted, and the electronics of the bus devices are supplied with energy. The KNX system can also be extended over IP-Networks.

Further system information

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