Hi,
so, I bought one of these smart knobs and when setting it up in Z2M, a few questions came up.
I could configure the knob in ‘command mode’ or ‘event mode’. IIUC, the difference is that in event mode it just sends rotate_left or rotate_right without information on how far or how fast it rotated. In command mode, there’s also a step_size available. So, command mode is superior to the event_mode. At least I cannot think of a scenario when someone would want to use event_mode at all.
I created automations to dim a zigbee bulb by step_size. It somewhat worked, but not really well. For some reason, when I dimmed brighter a few steps it worked fine, but if I then went back just one click, the light completely turned off. I have a feeling the brightness level was somehow not updated in HA and when dimming lower, it just went to the last known state minus step_size which was probably 0-x = 0.
- Q1: How could HA set the brightness but not know the resulting brightness level?
So, I did some research and found out that I can even bind the knob directly to the bulb using a device group. So, I simply put the knob and the bulb in the same group, deactivated the automation and it immediately worked without further configuration. Dimming up and down is very smooth.
- Q2: I thought this was what device binding is for. How could this work without even using device binding?!
Unfortunately, in this mode, HA does not reflect the current state of the bulb, as the knob and the bulb directly communicate without HA in between.
- Q3: Can I somehow update the HA state when the knob is used? Maybe an automation that pulls the state from the bulb whenever the knob is used?
Also, in this mode, the actions are not customizable. Rotating is dimming, clicking is toggling, hold+rotate changes the color temperature. So, ideally, I would probably like to use automations instead of this device group - that is, if Q1 can be solved and the control is smooth using automations, too.
Lastly, one thing I found out is that with the knob connected to the bulb via a device group, I can set the brightness level of the bulb without turning it on. I.e. if the bulb is turned off, I can rotate the knob to dim up or down. When I then turn on the lamp, either using HA or the button, the dimmed brightness level is set. This is a functionality I always really wanted to have, to not be flashed at night, but as I understood from other threads, it’s not supposed to be possible to change the brightness level without turning on the light briefly.
- Q4: Has this changed meanwhile, so it’s possible now? Or is it just this magical knob that can do the impossible?
Thanks in advance!