Bridge a KNX TP installation and a KNX IP backbone on a single WBox. The gateway works as a KNX IP router/interface: it couples the twisted-pair line to KNXnet/IP, so ETS, IP visualisations and other lines reach the TP devices over Ethernet.
The two networks
KNX TP
KNX TP (TP1) is the classic KNX twisted-pair field bus that powers sensors and actuators across a building.
KNX IP
KNX IP (KNXnet/IP) carries KNX over Ethernet — used as a fast backbone between lines and for tunnelling ETS or visualisations to the bus.
Typical use case
A building's lighting, blinds and HVAC run on KNX TP, but supervision, ETS programming or a second building need to reach the bus over IP. The WBox couples the TP line to KNXnet/IP: telegrams pass both ways, IP clients tunnel into the TP installation, and several TP lines can be linked over an IP backbone — no dedicated KNX/IP router required.
How the WBox bridges KNX TP and KNX IP
Use the WBox S485 KNX, which has the KNX TP interface on board, and enable KNXnet/IP routing and/or tunnelling. The gateway forwards group telegrams between the TP line and the IP multicast backbone, with a filter table so only the relevant groups cross. Tunnelling connections let ETS and visualisations talk to the TP devices remotely. The same WBox can additionally bridge KNX to other protocols.
Frequently asked questions
Is this a KNX IP router or a KNX IP interface?
Both roles are available: routing couples TP lines over an IP backbone with a filter table; tunnelling gives ETS or a visualisation a connection into the TP line. Pick either or both on the same WBox.
Which WBox model has the KNX TP interface?
The WBox S485 KNX has the KNX twisted-pair interface on board. Any WBox can speak KNXnet/IP over Ethernet; for the TP side you need the S485 KNX.
Can I reach the KNX bus from ETS remotely?
Yes. Over a tunnelling connection (combined with Weble remote access when off-site), ETS talks to the TP installation as if you were plugged into the line.
Does it filter telegrams or pass everything?
A filter table forwards only the group addresses that need to cross between TP and IP, keeping bus load down — standard KNX router behaviour, configured on the gateway.
What you need
A WBox S485 KNX (KNX TP interface on board) with the KNX driver licence handles both the TP and the IP side:
Route KNX TP KNX IP on your project
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