OH3 - No updates of KNX items

  • Platform information:
    • Hardware: Intel X86 / 6 GB
    • OS: Ubuntu server 18.04.4 LTS
    • Java Runtime Environment: _11.09
    • openHAB version: 3

I have managed to get my KNX install to connect to OH3. I can see the Bridge and the Things in the GUI,

using this Things file

Bridge knx:ip:bridge [
] {
Thing device Jung_IO [ address=“1.1.1”, fetch=true, pingInterval=300, readInterval=3600 ]
Type switch-control : IO_linje1 “IO 1” [ ga=“1/1/1” ]
Type switch-control : IO_linje2 “IO 2” [ ga=“1/1/2” ]
Type switch-control : IO_linje3 “IO 3” [ ga=“1/1/3” ]
Type switch-control : IO_linje4 “IO 4” [ ga=“1/1/4” ]

and this Items file

Switch demoSwitch1 “Switch1 [%s]” { channel=“knx:device:bridge:Jung_IO:IO_linje1” }
Switch demoSwitch2 “Switch2 [%s]” { channel=“knx:device:bridge:Jung_IO:IO_linje2” }
Switch demoSwitch3 “Switch3 [%s]” { channel=“knx:device:bridge:Jung_IO:IO_linje3” }
Switch demoSwitch4 “Switch3 [%s]” { channel=“knx:device:bridge:Jung_IO:IO_linje4” }

When I manipulate the KNX device (switch), I can see the correct ga´s being sent in ETS Group monitor, but I cannot get the items to update in OH. When I check the events.log it does not show any KNX activity, I have checked the openhab.log and both the bridge and the thing is loaded fine and online.

I must be doing something wrong, but I cannot figure out what. Any tips would be great.

Seems that there are some missing information for us. What do you want to have as the result? A switch-control is for linking KNX GA with other channels, like to control a hue or Zigbee light. If you have a real actuator and you want to control him with openHAB, you must configure a switch in the thing file.
And what I missed at the beginning are the response GA. You can define some for the switch-control, but in the moment they will not used, when I understand the documentation right. In a normal switch, openHAB uses them to get the status active.

Thanks for trying to help. Switch-control is the correct type as I am trying to let a KNX switch control a Traadfri Bulb.

However, I think I have found the answer. I had configured the KNX router incorrectly to filer KNX->IP. When I changed from “filter” to “route” on main groups 0-13 I am able to update the items in OH.

hi, i also have big problems updating items from bus knx.
knx tunnel ip
clean installation oh3

on oh2.5 everything works correctly.
trying version 3 it doesn’t update the items when I act as a physical knx button.
I set the GA adress: 0/0/0 [main] + <0/0/1 [state]
the only difference is that I configured everything from mainUI in 3, while in 2.5 I had the text files.


I don’t know if this solves your problem, but I would avoid using 0/0/0.

yes yes 0/0/0 and 0/0/1 I used them only as an example …
what i don’t understand is why if i turn on the rpi with oh2.5 it works, while if i start that oh3, i can command but i don’t see the updates to the items

I see. I have no idea why your setup is ok on 2,5,but not on 3.0. I would try the things- and item files and even post them here. Could be someone could help with a bit more information.

configuration oh3

Configurations OH2.5

change only localsourceaddr because was run a two OH instance.
OH2.5 can command and was update correctly.
OH3 can only command

The only thing I see is that fetch=false in OH3 config while fetch=true in OH2.5. What happens if you use the files from 2.5 config in 3.0?

Hi, I imported the files from OH2.5 to OH3 via VSC …
everything works but things remain offline.

Hi albeval,

…“everything works but things remain offline”? Sorry, I don’t understand. Do you mean that you are not getting any error messages in your log files (everything works), but you still cannot get any updates from the KNX bus showing in your items or things (things remain offline)?

If it works on 2.5 with the same files as you try on 3.0, I’m almost out of options. Except… do you have the ETS software so you can use the monitor features? If so, do that and check if the expected telegrams are sent on the knx bus. Also, some knx interfaces (are you sure you have an interface and not a router? what make and model do you have?) only allow one connection at the time. Others allow up to 5 simultaneous connections. How many does your interface support? If your interface only support one at the time and you already run OH2.5 on another device you will not be able to communicate with the bus, but you should get error msg in you log files.

In general you may need to describe the problem you’re facing a bit more precise to get the help you need. After you have found a way to describe the problem in more detail, you should create a new thread as this tread has been marked as solved (the check in the box for Solution).

Best of luck

Sorry I explained myself wrong …
with text files everything works fine, and I read all the states and command everything. the “thing”, however, is offline.
I just wanted to say that some small bugs from 2.5 to 3 exist, because in 2.5 I never had any problems, and programming the channels on 3 from mainUI someone does not update as I said.

I have an IP port of the MDT and it supports 4 connections. on the KNX side I have no problem and on the bus with the ETS monitor I see everything.


Ahh, I understand.

I think I will use the file based config for the Things and use the semantic model and GUI to create the Items for OH3. IN OH 2.5 is used files config only. Alas, I’m all out of suggestions to solve your issue. Best of luck though.

Hi, I am pretty new in the OH3 and KNX “business”

Right now my main problem is, that in my KNX bus I need to send an On and Off to the same adress. It looks like everyone else has one adresses for on and off.

Can you give me a hint how I do that?

Also I do not find a lot of informations what the KNXD stuff is in detail.

Do you know someone who is providing an onside support as an business?

Thank you


Sending ON and OFF to the same GA is normal for most devices. But there could be other GA’s for status and other stuff. Have you configured anything in openHAB yet?

It’s hard to help you because I have no information on your setup and configuration. On the KNX side of the equation you need to have a hardware device (router or interface) that connects the KNX bus to IP. When that is configured correctly, you can start to look at the openHAB side of things. The first thing you need is to install the KNX binding. From there you can create a THING (knx bridge) to represent your knx router or interface. This can be done configuring files or in the GUI. Once this is done, you must configure a thing to represent a switch, actuator, dimmer, or some other kind of knx physical device. Once that is configured, you need to create an item and connect that item to one of the channels on one of your things. Once that is configured, you should be able to send commands (ON/OFF) to the GA represented by your item in openHAB.

If you run your openHAB on linux and have a knx router configured, you could create a file and place it in your /etc/openhab/things directory. If you don’t have a router, this config file will not work. This is one of two ways to create things. Call the file knx.things and put the following content into it:

Bridge knx:ip:router "KNX/IP Router" [
  Thing device actuator_1_1_100 "actuator" [ address="1.1.100", fetch=true, pingInterval=300, readInterval=3600 ]
    Type switch : switch1  "Example Switch"  [ ga="1/0/4" ]

Then you could use the GUI in openHAB to create an item and connect to the thing named switch1.

The KNX documentation is pretty comprehensive KNX - Bindings | openHAB and there is usually a lot of help to be had in the community. I don’t know anyone that have made a business of this, but if you post a bit more information I and others in the community will try to help.


at first, thank you very much for the response on my Email.

I already defined the Items already like you mentioned (see below code out of OH3)

But right now I can only switch ON lights but never get it Off. I do not see a KNX command when I switch Off right now.

In the past I had it also in the opposite way (only turn it Off and never get it on again)

UID: knx:device:490301cdc8:f994fe278e
label: KNX Device
thingTypeUID: knx:device
pingInterval: 60
address: 1.1.8
readInterval: 10
fetch: true
bridgeUID: knx:ip:490301cdc8

  • id: Licht_UG_Buro
    channelTypeUID: knx:switch
    label: Licht Büro
    description: “”
    ga: 1/0/4

UID: knx:ip:490301cdc8
label: KNX/IP Gateway
thingTypeUID: knx:ip
useNAT: false
readRetriesLimit: 3
autoReconnectPeriod: 0
type: TUNNEL
localSourceAddr: 1.1.250
readingPause: 50
portNumber: 3671
responseTimeout: 10

I don’t have experience with defining the KNX items using the GUI. (I’m using a text based approach).
It looks to me that you lack the ga for the status of the item.
The binding info could help you. I think you are missing the listening address.


I tried all configuations I found in the documentation. Also if I do it like that
ga: 1/0/4+<1/0/4

It is really randome if I can switch only On or only OFF. It look like the KNX-command is not including the state of the switch.

You would not normally have the same address there. See other’s examples.