Smart poteniometer?

I’m getting a new exhaust fan for my house:

It has a built in potentiometer that you can adjust to control its speed. They also sell an external potentiometer:

That’s good and all but I would want to make it smarter. For example, increase fan speed if higher humidity is detected after a shower etc.

Is there any “smart” potentiometer (preferbly that also has a dial in case HA becomes outdated in 20 years) that you can buy of the shelf and integrate with HA? Looking at the external Controller above, it looks like it needs to output 0-10V?

Wifi, zigbee, zwave?

DIY or off-the-shelf?


One option is to set the fan to run at maximum speed and use a motor controller module (dimmer) rated for the (inductive) load. 35.5W is not a large load at all. There are plenty of devices that can control this.

I had a look at the manual - I don’t speak Swedish, but I can look at circuits. :grinning:
“Max effekt: 35,5W Vid 10V styrsignal. 11W vid 6V styrsignal”

Maybe this is a VFD (variable frequency drive) input and you could control this using an ESP32 with ESPHOME and PWM. It might need a couple of components on the output to convert the PWM into a usable voltage between 0v to 10v…

The only thing that I’ll say is that if you try to control it off a AC voltage dimmer you can mess it up as the fan already has a speed control, so unless you can override that you can’t have a controller on a controller.

Wifi or Zigbee, off-the-shelf, Sweden.

Its my understanding that the fan needs 0-10V for controlling the speed.

Yeah its an EC fan, not AC.

You might be able to if you set it to max and the fan controller is essentially doing nothing.

ok forget that idea.

Yes, Probably! But you just can’t use PWM on AC, it should be a fan speed controller for AC which uses AC peak detection or a MOSFET.

The slightly confusing part here is the VFD input on the fan as that takes 0v to 10v DC.

What’s EC? Do you mean DC?

Ok, I hadn’t known of the distinction!
In that case I think you need to use the VFD input and connect it using a PWM to voltage driver.
This was done in this posting, but there is no circuit diagram of the PWM to V.

But it seems that there is a device available for this:

I see it available locally to me for 7.10 EUR (inc VAT).
Perhaps this helps!

Hehe thanks but I have very limited knowledge with this stuff, hence why I wanted to buy something of the shelf.

Sadly, since I could not find a good option, I ended up using a “manual” potentiometer.

But will keep looking!

I found this thing, maybe it could work?

It needs 100-230V though so I guess not.

I did a similar search a few months ago!! I ended up switching out this exact dimmer from (I have had it to regulate my seemingly identical DC-fan in our greenhouse for a few years. Ever since I installed it the plan has been to automate this fan/speed with temperature, humidity, time of day and perhaps even weather forecast!!?.. via Home Assistant.)
I ended up buying a plejd ctr-01 and have had it controlling the fan-speed via the Plejld-app. It works perfectly… if you are within bluetooth reach!! Now I’ve been trying to integrate Plejd into Home Assistant and it seems like the Plejd-integration is now gone!? According to the home-page their gateway should be compatible… but I cannot find any real evidence that someone else has succeeded!!
So now I’m on the hunt again!!
My top wish would be a DIN rail mounted Z-wave 0-10V dimmer but I’m not comfortable enough with the electrical terms describing all the LED-dimmers that I have found. I will look at the zigbee dimmer mentioned here!

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Amazon is flooded eith 0-10V zigbee units. I bought one but never used it sadly…a bit skeptical hooking up chinese junk to. 230V. Also needs electrician to do it so its a bit expensive. Would still love to get this working some day.

I’m no electrician and my Swedish is zero to nothing. But wouldn’t this work: