Connection to Keymatic get's lost when executing OH rules

Hello everyone,

I use openHAB to control my Homematic components. For quite some time I have the problem that the connection to the Keymatic (HM-Sec-Key) often (not always) aborts with a communication error during rule execution:

2020-11-06 20:15:00.479 [ome.event.ItemCommandEvent] - Item 'schloss_garage_status' received command OFF
2020-11-06 20:15:00.550 [nt.ItemStatePredictedEvent] - schloss_garage_status predicted to become OFF
2020-11-06 20:15:00.810 [vent.ItemStateChangedEvent] - schloss_garage_status changed from ON to OFF
==> /var/log/openhab2/openhab.log <==
2020-11-06 20:15:02.617 [WARN ] [ternal.handler.HomematicThingHandler] - Device 'xxx' is OFFLINE, can't send command 'OFF' for channel 'homematic:HM-Sec-Key:ccu:xxx:1#STATE'
==> /var/log/openhab2/events.log <==
2020-11-06 20:15:02.640 [hingStatusInfoChangedEvent] - 'homematic:HM-Sec-Key:ccu:xxx' changed from ONLINE to OFFLINE (COMMUNICATION_ERROR)

The status will be changed with the following rules:

rule "Garagentür schließen"
    Time cron "0 15 20 * * ? *"
    if (schloss_garage_status.state == ON || schloss_garage_status.state == NULL) {

rule "Garagentür öffnen"
    Time cron "0 0 7 * * ? *"
    if (schloss_garage_status.state == OFF) {

In my opinion it is not the wireless connection, because I optimized it. By manually activating the Keymatic the connection to Homematic CCU will be re-established with SIGNALSTRENGTH=4.

I also realized in the OH log that the status changes more often than required:

2020-11-05 07:00:00.423 [ome.event.ItemCommandEvent] - Item 'schloss_garage_status' received command ON
2020-11-05 07:00:00.512 [nt.ItemStatePredictedEvent] - schloss_garage_status predicted to become ON
2020-11-05 07:00:00.771 [vent.ItemStateChangedEvent] - schloss_garage_status changed from OFF to ON
2020-11-05 07:00:01.996 [vent.ItemStateChangedEvent] - schloss_garage_status changed from ON to OFF
2020-11-05 07:00:06.114 [vent.ItemStateChangedEvent] - schloss_garage_status changed from OFF to ON

I assume that there is an issue with the binding. I created a program directly in the Homematic CCU which locks/unlocks the door and that works without any errors.

Is there a possibility to debug the binding-code or could anybody help me to fix this issue with the homematic-binding?

Thanks a lot for your support in advance!!!

That is not about the binding.
See “jitter and jumping” here -

1 Like

Thank you very much for this hint!!! That solved the issue and the Keymatic works now fine.