I have several Homematic IP HmIP-SWSD-2 smoke detectors that went off for the first time today during a thunderstorm. It was a false alarm. After about 10 seconds, the alarm turned off automatically. I have the Homematic IP integration set up in HA (Home Assistant), but the alarm didn't trigger my automation, nor is there any log entry for it. Where can I start checking why the alarm wasn't forwarded to HA? I can't see any log entry in the Homematic IP App, too.
Hi, welcome to the forum!
Do you have any automation that uses these sensors / the integration as a trigger?
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Hi Nick, yes I have. If they went off my shutters should moving up, door should go in evacuation mode and my ventilation system should stop working.
Maybe there was to much interference in the air during the thunderstorm so the smoke detector couldn't sent their signal to the Homematic IP Access Point. But as all smoke detectors in my house went off, they found a way to communicate with each other even without the Access Point.
|sensor.access_point_duty_cycle|0.5|2026-05-29T18:11:55.820Z|
|---|---|---|
|sensor.access_point_duty_cycle|0.0|2026-05-29T18:17:38.315Z|
|sensor.access_point_duty_cycle|0.5|2026-05-29T18:27:36.552Z|
|sensor.access_point_duty_cycle|0.0|2026-05-29T18:36:43.541Z|
|sensor.access_point_duty_cycle|3.0|2026-05-29T18:40:52.204Z|
|sensor.access_point_duty_cycle|3.5|2026-05-29T18:47:13.511Z|
|sensor.access_point_duty_cycle|0.5|2026-05-29T19:44:14.697Z|
|sensor.access_point_duty_cycle|0.0|2026-05-29T19:48:52.186Z|
|sensor.access_point_duty_cycle|unavailable|2026-05-29T19:49:37.351Z|
|sensor.access_point_duty_cycle|0.0|2026-05-29T19:50:56.996Z|
|sensor.access_point_duty_cycle|0.5|2026-05-29T19:54:04.945Z|
|sensor.access_point_duty_cycle|unavailable|2026-05-29T19:59:23.899Z|
|sensor.access_point_duty_cycle|0.0|2026-05-29T20:00:24.756Z|
|sensor.access_point_duty_cycle|0.5|2026-05-29T20:05:11.932Z|
Maybe because the duty cycle rised up to 3.5% smoke detectors wasn't able to use the frequence to contact the Access Point.
You can see in the traces (upper right corner while editing) of the automation(s), related to this, if there was any activity and what happened.
If there is nothing in the traces, you have to look further in the chain of this.
It's possible that the thunderstorm triggered the siren rather than the smoke detection entity - in which case HA was correct not to raise the shutters, etc.
Did the trigger entity in your automations actually change? Were they triggered by the entity becoming unavailable? If the latter you need to adjust the trigger.
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My HA automation haven't triggered, there are no Traces.
Did you see any activity, related to the incident, in one of the entities?
If so, and you used the right trigger in your automation, it should work.
There is no activity at all, not even in the Homematic IP Log.
Then it seems that there is an issue with the integration and the cloud platform.
What @RedKing said makes sense. Sounds more like the electricity spike triggered the siren directly without affecting the sensor.
In your case, that's what you want. You only want your automation to trigger if there's actual smoke detected by the sensors.
Homematic told me today, that all smoke detectors will be reached first, only if everyone was reached, alarm will be directed through the cloud and there will be a note to the log only then.
What if the duty cycle is completely used to reach all smoke detectors, there will not be a alarm to Homematic access point. Not sure how happy I should be about that.
Maybe I need some kind of sound detection for smoke detectors. That could work as a backup in this cases to trigger my automations even if the duty cycle is fully used or the access point can't be reached.
There are devices to do this, but the only ones I've been able to find are for professional installation only, and quite expensive. Apparently there are "official" siren sounds and the detectors avoid false positives by recognising those. If you can find something, this may be a good way to go because you wouldn't need a cloud connection at all.
Bear in mind that the only way to test smoke detection is to blow smoke into the device. This is how fire departments do it, and you can get DIY cans of "smoke" on Amazon if you want to try yourself. Anything else is only testing the siren - which perhaps explains your problem.
Edit: Burning the toast also works.
Not sure about availability or price, but I did spot this in last month's Z2M release Ecolink FFZB1-SM-ECO control via MQTT | Zigbee2MQTT