I am buying these light switches for my house: WiFi Knobs For Dimmer Switches|Smart Light Dimable Rotary Switch – MOES
(the zigbee variant)
However, I’m not sure if it’s possible to have 2 or more of these on the same loop in order to control the same light? I’m not really good with electricity.
EDIT: I think I figured it out: if you connect the L1 from one switch to the L of the other, you are controlling one switch with the other
Hi Robin, welcome to the forum!
Unless I’m completely off: these switches take their power from your grid but control the lights over zigbee.
This implicates that you can have multiple switches controlling 1 (or more, ie a group or otherwise) light(s) because you communicate over zigbee via your HA.
Not sure that this is the exact model that you are interested in, but here is some info: TuYa TS0601_dimmer_knob control via MQTT | Zigbee2MQTT (coming from | Zigbee2MQTT)
you can have as many switches as you want
switch reports to HA, an automation turns on/off the light.
However, dimmers is another story, you cannot connect them in series (nor parallel)
Hi aceindy, I don’t have multiple dimmers for the same light(s) but is this any/so different from using multiple switches for the same device(s)?
You’re just sending HA the command to increase/dim a light, no matter where that command comes from, no?
If you look at the wiring diagram, @DeWolfRobin suggested to put the switches(?) in series.
That won’t be possible I’m afraid, but parallel shouldn’t be an issue (although you’de have to switch off both switches in order to switch off the light, but it is possbile to synchronise them through HA)
Still it would be better to seperate them alltogether; just use a seperate (zigbee) switch not controlling a light directly, but a zigbee lamp.
HA should be the ’ man-in-the-middle’ always 
No.
The load specs are:
By putting them in series the second dimmer will be receiving the line voltage from the first, chopped up into small chunks. This is how the TRIAC dimmers work, they chop up the line voltage according to the dim level selected.
What MIGHT work-- and I’ve never seen this control…
Wire one dimmer to the light as shown in the installation diagram.
Wire the second dimmer with nothing connected to the “Load” terminal.
The first dimmer controls the light and the second dimmer just sends data to Home Assistant where an automation then overrides whatever the first dimmer has set.
Owkay, got it all wrong… 
Thanks all for the information! I’m starting to get how everything works now. I might just put normal switches in places where they need to be put in serie. It’s just that some rooms of my house have two entrances or are just too big for only one switch.
Series will still have the issue that you have to turn them both on in order to turn on the light.
What you need is a so called ‘hotel switch’ or ‘3-way switch’
With this you will always be able to turn on/off the lamp regardless of which switch you use.
This can even be extended with a 3rd (or 4th, 5th etc) switch in the middle:
And this can also be used with a f.e. Shelly switch:
More info can be found here
Very nicely explained, and good graphics. Thanks for posting and thanks for the link to the source.
