Troubleshooting guide
This section is related to troubleshooting problems related to the KNX implementation in Shelly. For general KNX troubleshooting, please refer to a professional KNX installer and the respective KNX resources.
Multiple devices using the same
Individual address
Such case may arise only if devices are configured (programmed) using different software not connected one to another (e.g. Shelly embedded web interface and ETS software). In case of multiple devices are using the sameIndividual addressthis does not violate the operation of the KNX network, but it prevents proper fault diagnostics when such a case occur.Improper
Group addressassignment
Encoding of KNX Group addresses, i.e. their DPT type, is automatically assigned according to the firstobjectadded to that address. Then a case may arise where the DPT type of anobjectand the DPT type of theGroup addressto which is assigned do not mach. For example aGroup addresswith DPT 1.001 (switch) may be assigned to aLong push objectused for 4-bit dimming control, i.e. DPT 3.007 (dimming) may be done by a mistake. Shelly’s embedded web interface can not check such cases allowing the user to assign anyGroup address. When such is the case this will lead to inability to operate the improperly configured device, but will not affect the rest of the KNX installation.-
TOGGLE function not working
TOGGLE function is solely dependent on controlled channel feedback status. In case this function is not working properly might be due to missing or incorrectly assignedGroup addressfor the related to that functionFeedback object. Check if TOGGLE’s functionFeedback objectand the controlled channelFeedback objectshare the sameGroup address.
Controlled channelFeedback objectmust have its Read Flag active otherwise the TOGGLE function won’t work.
In this case Manually modifying the Communication Flags ofKNX objectsis neccessary.
Some KNX manufacturers DO NOT set the Read Flag as Active (see Pic. 1) on their Switch actuators' Channel [X]Feedback object. When the Read Flag is not enabled the TOGGLE function of Shelly devices won’t work!
Pic. 1 Read Flag is NOT Set, i.e. it is NOT Active!
When such case occur, the Read Flag should be manually enabled via the ETS (or other) configuration software. Select the
KNX objectwhich you need to modify and then Navigate to its Flags Properties - may be found at the right side of the ETS configuration software under Properties → Flags (See Pic. 2 and Pic. 3).
![]() Pic. 2 KNX object Flags |
Should be modified to: |
![]() Pic. 3 Manually modifying KNX object Flags |
Pic. 4 shows how the configuration should look like once all the Read Flags are Set on all (or user needed) of the switch actuator channels.

Pic. 4 Read Flags are Set, i.e. they are Active!
Note that the KNX manufacturers may give different names on their equipment for the Switch object and for the Feedback object. For example in the case above, for Channel [X] (1-4) the manufacturer is using R[X] Input for Switch object and R[X] Output for Feedback pobject.
You have to transfer all of the changes made back onto the affected KNX devices.

