PWM input for Fan (Using RGBW2)

    I am looking to purchase this 2 of these fans for both my remote kitchen exhaust and also my Makeup air, and would like to control it via Shelly devices.

    But looking at the manual it seems that PWM (0-10v) is available for the speed control.

    Could I use a Shelly RGBW2 as a fully variable control for this via PWM? From my checking of the manuals this seems to be pretty straight forward..., I assume I could even skip the "ground" as the fan is already powered and this is just providing the input

    Bottom left diagram is what I am thinking.

    pasted-from-clipboard.png

    There‘s a good chance for a success! Did some months ago nearly the same with a BELIMO servo drive:

    Thema

    Shelly RGBW2 und Belimo Stellantrieb

    Beim Aufräumen fiel mir "zwischen den Jahren" ein BELIMO-Stellantrieb mit 0-10V-Ansteuerung in die Hände, den ich vor vielen Jahren aus der Schrottkiste meines Arbeitgebers gerettet hatte:

    smarthome-forum.eu/attachment/26173/

    Der müsste doch eigentlich an einen Kanal des Shelly RGBW2 anschaltbar sein?

    Das Typenschild zeigt die verschiedenen Möglichkeiten:

    smarthome-forum.eu/attachment/26172/

    Habe mich für die Ansteuerung mit 0 bis 10 V entschlossen, weil auch andere Artikel der Steuer- und…
    thgoebel
    31. Dezember 2021 um 15:18

    An additional resistor between 0-10V input and plus 10V (or 12V) will be necessary.

    „Habt Geduld. Alle Dinge sind schwierig, bevor sie einfach werden!“ (aus Frankreich)

    „Nothing in life is to be feared, it is only to be understood.“ (Marie Curie, 1867-1934)

    „Es reicht nicht“, rief Schiller, „Gedankenfreiheit zu fordern, man muß auch denken können, sonst fordert man Gedankenlosigkeitsfreiheit und die ist die Freiheit zur Dummheit, welche wiederum die schlimmste Unfreiheit überhaupt ist!“
    (Aus „Besuch aus Weimar“ von Gert Heidenreich, Schriftsteller, *1944 in Eberswalde)

    Thanks for that thgoebel thats really good to know.

    It would be really great to have more support for a product like this, I am finding a lot of consumer devices running the controls of 0-1v. (I am used to it at work in the industrial sector where 0-10 or 1-24v is common)

    Zitat

    I am looking to purchase this 2 of these fans for both my remote kitchen exhaust and also my Makeup air, and would like to control it via Shelly devices.

    But looking at the manual it seems that PWM (0-10v) is available for the speed control.

    Could I use a Shelly RGBW2 as a fully variable control for this via PWM? From my checking of the manuals this seems to be pretty straight forward..., I assume I could even skip the "ground" as the fan is already powered and this is just providing the input

    Bottom left diagram is what I am thinking.

    pasted-from-clipboard.png

    I tested this for a project a year or two ago, you will need to add a protection diode for the Shelly, protect against back emf from the motor.

    You should also be aware that the shelly switches the ground not the supply so you have to change wiring to accommodate this.

    It does work, speed control is fully variable and very granular.

    There is another issue but it might not be a problem for your application, the PWM is set at 960Hz and this means the motor is very noisy with this frequency, like a loudspeaker, especially at slow speeds.

    The chip used in the RGBW2 can't run faster PWM, I have a feature request lodged for when/if they release an RGBW Plus based on the ESP32 that they have a motor mode where PWM is set to 32kHz which EPS32 can do.