KNX notes06 entries
Problems worth ten minutes, and what your file says about each one
Written for integrators, not for the people you sell to. Every one of these ends at something Readback finds in your own project, because a page that diagnoses a problem and then shrugs is a blog post.
- 01The light works, but the app says it is on when it is off. Why?Why a KNX light shows the wrong state in Home AssistantThe app can switch the light, but it cannot see what the light is doing, because the status object has no group address. Give it one and the app can show the real state.Finds it Missing status addresses — every status object the product declares, against the ones this installation actually wired.3 min
- 02Does it matter if a group address has no DPT set in ETS?Every group address with no datapoint type, and what it costs you laterA blank datapoint type does not stop the light working. It makes the project harder to read for the next person, and for every tool that reads it.Finds it Address problems — group addresses with no datapoint type, listed with the ETS Function role that would determine the right one.3 min
- 03I inherited a project where nothing is named. Which addresses are status?How to tell a status address from a control address when nobody named themDo not trust the name or the address range. Look at the flags on the objects linked to the address, then look at what the object does.Finds it Which addresses report, which command — every group address classified by the flags of the objects bound to it, and a list of the ones that are genuinely ambiguous.3 min
- 04My project has duplicate group address names. Is that actually a problem?Two group addresses with the same name: which one did you mean?KNX does not care if two addresses have the same name. People and tools do, and they may pick the wrong one.Finds it Address problems — duplicate names, listed with every address that shares each one.3 min
- 05How do I prove a KNX install is right before handover, not after?Commissioning a KNX house without walking it twiceWalking the house shows that an output is alive. It does not show a wrong room, a missing status object or dead feedback. A written test list does.Finds it A handover test list — every command, the status telegram it should produce, and an explicit list of what cannot be checked at all.3 min
- 06Why does writing a handover document take a week when the project has it all?Your ETS project already knows the rooms. Your handover pack does not.The rooms, the device list and the device settings are already in the project file. They are not in a form you can give to a client.Finds it A handover document generated from the project — building structure, device schedule, and the device-local behaviour that appears in no documentation.2 min
Every one of these is in a project file you already have.
Drop it in and find out which of them are in yours. Free to use, no card, about a minute.