Problems with Alexa ON/OFF command with MQTT and Dimmer in Version 2.4.0

  • Platform information:
    • Hardware: Raspberry
    • openHAB version: 2.4.0 -> Docker: openhab:latest

I want to handle my dimmers with Alexa. All components in my house are connected via MQTT.
The dimmers are from homematik and needed a value between 0 and 1.

My Things Konfiguration:
Thing mqtt:topic:homewz “Homematic WZ” (mqtt:broker:barney) {
Channels:
Type number : DimEz “Esszimmer” [stateTopic=“homegear/hg1/plain/10/1/LEVEL”,commandTopic=“homegear/hg1/set/10/1/LEVEL”,min=“0” ,max=“1” ,step=“0.1”] }

My Items Konfiguration:
Dimmer DimEz “Esszimmer” (gWohnzimmer, ALicht, EG_Wohnraum) {alexa=“PowerController.powerState,BrightnessController.brightness”, channel=“mqtt:topic:homewz:DimEz” }`

My Problem:

  1. I can handle the dimmer with the slider in the paperui. The right values are sent to mqtt topic
  2. If I say “alexa schalte Esszimmer auf 50%” the value is sent correctly to the topic
  3. If I say “alexa schalte Esszimmer ein”, I can see this in the log file, but no message is sent to topic.

I also see no log entries in kafka console for the mqtt binding. perhaps I have change the wrong packet name?

Logger │ Level
───────────────────────────────
org.openhab.binding │ DEBUG
org.openhab.binding.mqtt │ DEBUG

Log entry for handling %-Values: “Alexa schalte Esszimmer auf 70%”

11:28:02.182 [INFO ] [smarthome.event.ItemCommandEvent ] - Item ‘DimEz’ received command 70
11:28:02.240 [INFO ] [arthome.event.ItemStatePredictedEvent] - DimEz predicted to become 70
11:28:02.251 [INFO ] [smarthome.event.ItemStateChangedEvent] - DimEz changed from 100 to 70
11:28:02.449 [INFO ] [smarthome.event.ItemStateChangedEvent] - DimEz changed from 70 to 51.500
11:28:02.492 [INFO ] [smarthome.event.ItemStateChangedEvent] - DimEz changed from 51.500 to 70.0
==> Topic value: 0.70

Log entry for handling ON/OFF values: “Alexa schalte Esszimmer aus”
11:29:55.148 [INFO ] [smarthome.event.ItemCommandEvent ] - Item ‘DimEz’ received command OFF
11:29:55.166 [INFO ] [arthome.event.ItemStatePredictedEvent] - DimEz predicted to become OFF
11:29:55.193 [INFO ] [smarthome.event.ItemStateChangedEvent] - DimEz changed from 70.0 to 0
==> Topic value: still 0.70 - No value sent

The binding doesn’t know this is a dimmer. It doesn’t know what to do with ON/OFF commands to a number.

If I use the dimmer for type, then the min, max and steps values are not working, and values between 0 - 100 are published