The reason you don’t use variable_set directly to set the brightness of a lamp (or most other parameters) is that the variable is only storage to tell you state, changing it does not cause communication with the device. So, you use actions to make something happen on the device, and this as a side-effect causes variables to change to reflect what the action has done.
Hope this helps.
Edit: By the way, don’t waste time on the “Get” actions. They exist because they are part of the UPnP standard service definition, but that’s the hard way and not necessary on Vera except in a few rare cases.
luup.call_action(“urn:upnp-org:serviceId:Dimming1”, “SetLoadLevelTarget”, {newLoadlevelTarget = R_Wohnzimmer_save}, W_Wohnzimmer) – RGB White
That should read the value of the red channel and paste it to the white channel. Since I’m not at home, that’s the only way to check if it works. But the white channel is set to “0” even if the red channel is set to “3”. Is there any way to take a look at the variables? I’ve typed print(R_Wohnzimmer_save) and the code seem to work, but where can I see the output?