Idiots guide to getting an esp32 to control AC Infinity Cloudline EC fans esphome/HA

[sle118]

Hi guys,

I'm not a EE, I only know basic electronics, but I want to be able to control the speed of a S8 fan that I got this year (UIS connector). It has a manual speed controller but I want to be able to control the speed with either EPS32 or Arduino, and eventually integrate it into Home Assistant.

I tried to read this thread in its entirety but due to my limited EE knowledge, it's hard to follow. Can someone more knowledgeable summarize the key learnings please? I think what I got from it is that it uses a 10V PWM, at perhaps 5000 HZ. I know a little bit about MOSFET and PWM. I wonder what's the simplest circuit I can build to do this? Moreover, there's some historical changes between the MOLEX connector and the UIS which further makes this thread hard to follow.

Is it possible to achieve what I need without messing with the circuitry/wires inside the fan electronic box? In other words, just build an external DIY controller that connects to the fan using UIS (or USB-C?).

Someone please make it a truly idiot's guide. Thanks

You got it right. I'm sure you can achieve control without needing with wires, but you'd have to confirm the pins on the connector.

PWM is 4,156hz on my S4. See my measured trace here at various duty cycles:

https://www.rollitup.org/t/idiots-g...line-ec-fans-esphome-ha.1053910/post-17527413

The fans are likely tolerant to some level of deviations, though, and it is also possible that other models have slightly different frequencies but unless someone plugs in a scope of other models, your guess is as good as mine.

Your best bet is to at least open the fan case to peek inside and see for yourself what connections are there. @ImaginaryTango posted a nice picture of his unit and this is likely resembling yours as well.

My take on the base circuit is here.

Idiots guide to getting an esp32 to control AC Infinity Cloudline EC fans esphome/HA

Looks like there is a few of us working on these! This is the V1 and we are just working on a separate dosing station for ph/ec/temp and pumps along with embedded ESP32 etc.

www.rollitup.org

You can skip the fuse if you feel lucky. You can also skip the tachometer gpio too, although it's simple to add and brings interesting stats back.

 

[engineheat]

You got it right. I'm sure you can achieve control without needing with wires, but you'd have to confirm the pins on the connector.

PWM is 4,156hz on my S4. See my measured trace here at various duty cycles:

https://www.rollitup.org/t/idiots-g...line-ec-fans-esphome-ha.1053910/post-17527413

The fans are likely tolerant to some level of deviations, though, and it is also possible that other models have slightly different frequencies but unless someone plugs in a scope of other models, your guess is as good as mine.

Your best bet is to at least open the fan case to peek inside and see for yourself what connections are there. @ImaginaryTango posted a nice picture of his unit and this is likely resembling yours as well.

My take on the base circuit is here.

Idiots guide to getting an esp32 to control AC Infinity Cloudline EC fans esphome/HA

Looks like there is a few of us working on these! This is the V1 and we are just working on a separate dosing station for ph/ec/temp and pumps along with embedded ESP32 etc.

www.rollitup.org

You can skip the fuse if you feel lucky. You can also skip the tachometer gpio too, although it's simple to add and brings interesting stats back.

Thanks. I did read that someone was able to build a controller without modifying the internal electronics of the fan, such that they can still use the AC Infinity manual controller if needed. I also read that there is a 10V line inside and the PWM is coming off that. That 10V is DC, so is the motor actually a DC motor despite the S series being AC (in the sense you plug it into 110 - 220V AC)? Or is the 10V just for PWM?

It also seems like there the 10V for the PWM is being pulled up, such that when there is no controller connected, the fan is at full speed, and the purpose of the controller is to short it to ground in a periodic manner to achieve PWM. Did I understand it correctly?
Thanks

 

[sle118]

Thanks. I did read that someone was able to build a controller without modifying the internal electronics of the fan, such that they can still use the AC Infinity manual controller if needed. I also read that there is a 10V line inside and the PWM is coming off that. That 10V is DC, so is the motor actually a DC motor despite the S series being AC (in the sense you plug it into 110 - 220V AC)? Or is the 10V just for PWM?

It also seems like there the 10V for the PWM is being pulled up, such that when there is no controller connected, the fan is at full speed, and the purpose of the controller is to short it to ground in a periodic manner to achieve PWM. Did I understand it correctly?
Thanks

Yes you understood correctly. None of the suggestions here modify the inner circuit of the fan. Opening the fan cover merely gives you a different access to the wiring. Sending a PWM is a substitute for the out of the box controller. My post with scope captures were taken from the controller that came with the fan.

 

[ImaginaryTango]

I had to set this aside to get some other work done, and now I'm finally able to get back to it. I want to be sure I'm doing things right before I hook my ESP32 up to the fans. I bought a low end o-scope and used it to verify the square wave signal from the ESP32. So, for immediate questions, I mainly want to know about the wiring. I'm using the wiring diagram from the top of the compartment on the AC Infinity fans:

(Note, to avoid confusion, earlier we determined PE is Power Earth, or the ground line in the AC cord and FG is Frame Ground, or the ground for the device. I refer to it as Fan Ground in a diagram - my mistake there!)

I'm using, as reference, the wiring photo from the first post on the thread. It looks to me like this is how I should wire the MOSFET:

Can someone please verify for me thta I have the write wiring diagram for this?

Also, I see different valued resistors in the PWM OUT line from the ESP32 (I'm using GPIO4 for this). This is the same MOSFET everyone seems to be using (but without a screw terminal for the GND and TRIG lines. Do I need a resistor there, on the yellow line on the right, that runs from the ESP32 GPI4 to the TRIG on the MOSFET?

If I have this all correct and can make it work, then I have a few other questions. I've brought this issue up before, but I don't see an answer to it. With this particular setup, I want to control 2 fans and, of course, if I can do it with one ESP32, that'd save cost and setup time (and maintenence in the long run, keeping up 1 controller instead of 2).

If I'm using one ESP32 to control more than one fan, can I tie the ground lines from all the fans together? I would think, since they're all powered on the same AC circuit (all on the same breaker), they'll all have the sme PE, so it shouldn't be a problem. But, there's also the issue of the +10V lines from the fans. Can I tie them together, as well? I would think so, but I'd rather hear from someone who knows what they're talking about than trust my limited experience in this. I've seen discussion about using the +10V line from the fan to power the ESP32. That'd be quite useful! I would think just using the line from the 1st fan would do that, but I'm wondering if there would be an issue drawing power from only 1 fan out of 2 or more.

One reason I'm looking at this is I'm thinking of making a circuit board that would go in a box, like the original fan controller, and it'd hook up to the fan through the USB-C cable that is used for the original controller. That includes a +10V power supply on the USB connectors. If I could use that for power, there'd be no need for an AC adaptor to power the ESP32.

 

[Inthecountry]

I had to set this aside to get some other work done, and now I'm finally able to get back to it. I want to be sure I'm doing things right before I hook my ESP32 up to the fans. I bought a low end o-scope and used it to verify the square wave signal from the ESP32. So, for immediate questions, I mainly want to know about the wiring. I'm using the wiring diagram from the top of the compartment on the AC Infinity fans:
View attachment 5428863
(Note, to avoid confusion, earlier we determined PE is Power Earth, or the ground line in the AC cord and FG is Frame Ground, or the ground for the device. I refer to it as Fan Ground in a diagram - my mistake there!)

I'm using, as reference, the wiring photo from the first post on the thread. It looks to me like this is how I should wire the MOSFET:
View attachment 5428864
Can someone please verify for me thta I have the write wiring diagram for this?

Also, I see different valued resistors in the PWM OUT line from the ESP32 (I'm using GPIO4 for this). This is the same MOSFET everyone seems to be using (but without a screw terminal for the GND and TRIG lines. Do I need a resistor there, on the yellow line on the right, that runs from the ESP32 GPI4 to the TRIG on the MOSFET?

If I have this all correct and can make it work, then I have a few other questions. I've brought this issue up before, but I don't see an answer to it. With this particular setup, I want to control 2 fans and, of course, if I can do it with one ESP32, that'd save cost and setup time (and maintenence in the long run, keeping up 1 controller instead of 2).

If I'm using one ESP32 to control more than one fan, can I tie the ground lines from all the fans together? I would think, since they're all powered on the same AC circuit (all on the same breaker), they'll all have the sme PE, so it shouldn't be a problem. But, there's also the issue of the +10V lines from the fans. Can I tie them together, as well? I would think so, but I'd rather hear from someone who knows what they're talking about than trust my limited experience in this. I've seen discussion about using the +10V line from the fan to power the ESP32. That'd be quite useful! I would think just using the line from the 1st fan would do that, but I'm wondering if there would be an issue drawing power from only 1 fan out of 2 or more.

One reason I'm looking at this is I'm thinking of making a circuit board that would go in a box, like the original fan controller, and it'd hook up to the fan through the USB-C cable that is used for the original controller. That includes a +10V power supply on the USB connectors. If I could use that for power, there'd be no need for an AC adaptor to power the ESP32.

Did you ever get any further with this, I'm looking to buy a Cloudline fan and would like to have external control of the fan speed via ESp32 and home assistant.
A

 

[ImaginaryTango]

Did you ever get any further with this, I'm looking to buy a Cloudline fan and would like to have external control of the fan speed via ESp32 and home assistant.
A

I did get it working - basically I used the info from here and got a schematic together. I don't have my notes here - I'm at the workshop and they're on my the computer in the house. I don't have a PCB or anything, I just have it running on a breadboard using the ESPHome config given.

 

[Inthecountry]

I did get it working - basically I used the info from here and got a schematic together. I don't have my notes here - I'm at the workshop and they're on my the computer in the house. I don't have a PCB or anything, I just have it running on a breadboard using the ESPHome config given.

Thats good news, I have seen a few different schematics and configs, when you get a chance would you be able to let me have details of the ones you used as they work. Did you just manage to plug it into the fan using the USB connection?

Thanks

 

[ImaginaryTango]

Thats good news, I have seen a few different schematics and configs, when you get a chance would you be able to let me have details of the ones you used as they work. Did you just manage to plug it into the fan using the USB connection?

Thanks

What I do remember is that the fan provides +10VDC through the USB-C connector. That's helpful here, but bad otherwise. For a USB-C connector, most hardware will expect +5VDC, and NOT 10, so when they do this, that could break a person's hardware.

Here's what I remember about what I did:

I used 4 USB-C connectors in the design, so it can work for up to 4 fans from one board. There is no power supply from an outside source. I drew power directly from the +10V line on the USB-C cable. I put diodes in to isolate the power line for each USB connector, so there won't be problems with one fan getting +10V when it's not plugged in. As long as one fan is plugged in, the board gets power. (And if it's not connected to a plugged-in fan, it doesn't need power because it's not doing anything!) I used a simple +5V power regulator chip to provide +5V (come to think of it, I might have used 3.3V - not sure) and used that to power the ESP32. I used one GPIO per fan, it drives a MOSFET and there are a few other components for each fan, like pull-up or pull-down resistors. (Have to find the schematic to be sure!) It's a simple circuit that I just used 4 times, once per fan. I did not use the MOSFET several people used here (and have photographed), since that costs more and is on its own small PCB and harder to set up, on a breadboard or on a PCB when I can finally design and use one, and found a MOSFET that does the job fine, for a lower cost and for using less space.

I used the configuration given in this thread for ESPHome. I found, when I tried to use ESPHome for other uses, or tried to add or modify features, to be overly complex in some things, but I found I could always get help on the forums for it on the Home Assistant forums. I looked into other software for the ESP32, but didn't always get the help I needed. ESPHome has forums, and others have Discord channels. (Some don't even have a subreddit.) I find that a forum or a subreddit is better for getting help since, in chat, your request can scroll off and if people don't catch it in real time, it can be tough to get help. (And fewer people see your questions than if it's in a forum.) I did look at one other system that has PWM in their configuration, but the PWM frequency is a lot higher than the one the AC Infinity fans are known to work with. I could never verify it was true PWM because I have a cheap $40 oscilloscope and am not yet at the point where I can justify spending the $300-$350 to get a good one. (So mine doesn't work for but so high a frequency.) On one of them, I tried compiling it myself, using a smaller number for the PWM frequency - but, again, my cheap scope didn't show a true PWM wave. Supposedly it works, but I could only verify the output was a true PWM signal at VERY low frequencies. I've blown out one fan before, and I'm not going to trust a fan with a control circuit unless I know it's outputting the frequency and signal I know is compatible with the fan.

The more I write about this, the more I remember about it, so I'll try to answer what questions I can at this point, since it seems like this thread has dried up and not many people are responding anymore.

 

[ImaginaryTango]

Found it!



So it was a transistor - I can't remember the specs, but it's fast enough. I bought all the parts from Amazon. The ESP32 is a WROOM, so be aware that the pin numbers might change depending on which version of the ESP32 you use.

 

[Inthecountry]

Found it!

View attachment 5457344

So it was a transistor - I can't remember the specs, but it's fast enough. I bought all the parts from Amazon. The ESP32 is a WROOM, so be aware that the pin numbers might change depending on which version of the ESP32 you use.

Thanks very much for this, I have ordered my parts, just waiting for them to arrive

Looking at the ESP code do you remember if you used 1000 or 4156hz as the frequency, I have seen both quoted here

thanks again

A

 

[ImaginaryTango]

Thanks very much for this, I have ordered my parts, just waiting for them to arrive

Looking at the ESP code do you remember if you used 1000 or 4156hz as the frequency, I have seen both quoted here

thanks again

A

I used 1 Khz. I ran into issues because I also wanted to see if i could get this to work on another ESP32 system. It was either Tasmota or OpenHASP. I ran into multiple issues with that. First, my oscilloscope couldn't handle the 10Khz that I think they were using and, as you point out, there's the approximately 4Khz frequency that is supposedly native to the fan itself. (And I AM NOT about to test my fan on 10Khz - I've blown out one $90 fan. I'm NOT going to blow out another!

I think it was Tasmota I was working, as I said, I can't remember, so I changed the code to use a 1Khz frequency and my scope STILL didn't pick it up - and yet it picked up 1Khz on ESPHome. So something is wrong in that situation. It could be a problem with my scope or with the software - but it does work fine on ESPHome.

I'm also working on a control box to connect to my CNC so when I turn the CNC laser on, it'll turn the fan on automatically. When I turn the laser off, there will be an adjustable delay that will automatically turn the vent off after it's had time to clear the smoke from the CNC vent hood.

 

[niloc85]

Has anyone tried this with a CLOUDLIFT S12 AC-WFS12?

 

[Inthecountry]

I used 1 Khz. I ran into issues because I also wanted to see if i could get this to work on another ESP32 system. It was either Tasmota or OpenHASP. I ran into multiple issues with that. First, my oscilloscope couldn't handle the 10Khz that I think they were using and, as you point out, there's the approximately 4Khz frequency that is supposedly native to the fan itself. (And I AM NOT about to test my fan on 10Khz - I've blown out one $90 fan. I'm NOT going to blow out another!

I think it was Tasmota I was working, as I said, I can't remember, so I changed the code to use a 1Khz frequency and my scope STILL didn't pick it up - and yet it picked up 1Khz on ESPHome. So something is wrong in that situation. It could be a problem with my scope or with the software - but it does work fine on ESPHome.

I'm also working on a control box to connect to my CNC so when I turn the CNC laser on, it'll turn the fan on automatically. When I turn the laser off, there will be an adjustable delay that will automatically turn the vent off after it's had time to clear the smoke from the CNC vent hood.

Thanks for that, will give a try soon,
Re the CNC control you were talking about, could you not connect a BME680 to one ot the other GPIO pins and use that to switch the fans on, it has gas detection. Do you use home assistant so you could control the fan speed and delay etc as well

 

[edrfhtyj]

Anyone willing to walk me through making a single unit that just plugs into the usb-c and works? I have a bunch of gear from these guys (4 cloudlift s12/s14s primarily) and it would be super awesome to be able to make something a reasonable size that I just plug in to the fan to make it home assistant compatible. I could see myself buying more of their stuff for other projects if I can get help figuring that out.

 

[ImaginaryTango]

Anyone willing to walk me through making a single unit that just plugs into the usb-c and works? I have a bunch of gear from these guys (4 cloudlift s12/s14s primarily) and it would be super awesome to be able to make something a reasonable size that I just plug in to the fan to make it home assistant compatible. I could see myself buying more of their stuff for other projects if I can get help figuring that out.

Just how simple do you want it? I know this is a long thread, but all you need is in here. If you want just a "black box" that will do it, that's quite a bit for someone else to do. If, by "walk me through" do you mean basically giving you a PCB design and telling you what components you need for it? It's not clear just how much you know and how much help you need.

 

[edrfhtyj]

Just how simple do you want it? I know this is a long thread, but all you need is in here. If you want just a "black box" that will do it, that's quite a bit for someone else to do. If, by "walk me through" do you mean basically giving you a PCB design and telling you what components you need for it? It's not clear just how much you know and how much help you need.

Something as simple as a parts list and wiring explanation to get a single unit going with an esp32. ideally powered by the usb-c and controlling the fan by the usb-c (if that makes it infeasible, I could power it via the microusb on with a power adapater, it just makes it way uglier), I can solder it all together myself. I saw one guy who appears to have gotten it going but I didn't see any confirmation of it really working other than it seemed to work in a test configuration and it had a mosfet which looked kind of large for the esp32 enclosures I have. It was also quite far back in the thread and a lot of extra work and understanding seems to have happened since that comment but has been applied to multi unit control, which doesn't work in my use case. I'm basically looking for a bit of clarification if anything has changed for the single unit case and a bit of a clearer for a lay person explanation/drawing of the wiring I need to solder up to what parts.

 

[ImaginaryTango]

Something as simple as a parts list and wiring explanation to get a single unit going with an esp32. ideally powered by the usb-c and controlling the fan by the usb-c (if that makes it infeasible, I could power it via the microusb on with a power adapater, it just makes it way uglier), I can solder it all together myself. I saw one guy who appears to have gotten it going but I didn't see any confirmation of it really working other than it seemed to work in a test configuration and it had a mosfet which looked kind of large for the esp32 enclosures I have. It was also quite far back in the thread and a lot of extra work and understanding seems to have happened since that comment but has been applied to multi unit control, which doesn't work in my use case. I'm basically looking for a bit of clarification if anything has changed for the single unit case and a bit of a clearer for a lay person explanation/drawing of the wiring I need to solder up to what parts.

I'm about to go to sleep and it's late, so I can't get too in depth, but don't focus on the USB aspect. While it has a USB-C connector, it uses a +10V power line. While the IO lines do match the specs for USB-C, you have to allow for the +10V instead of +5V, so you're going to have to use either a breadboard or circuit board to build the circuit and connect to the USB-C connector on the fan, but you can't think of it as an actual USB connector, since you can't connect it to a computer or to most devices using a USB-C bus.

Have you looked over the thread? Because a lot of what you're asking can be found on this thread. You're basically asking to be handed a design that many people here have worked out in this thread and you're asking for some answers that are already here.

 

[edrfhtyj]

I'm about to go to sleep and it's late, so I can't get too in depth, but don't focus on the USB aspect. While it has a USB-C connector, it uses a +10V power line. While the IO lines do match the specs for USB-C, you have to allow for the +10V instead of +5V, so you're going to have to use either a breadboard or circuit board to build the circuit and connect to the USB-C connector on the fan, but you can't think of it as an actual USB connector, since you can't connect it to a computer or to most devices using a USB-C bus.

Have you looked over the thread? Because a lot of what you're asking can be found on this thread. You're basically asking to be handed a design that many people here have worked out in this thread and you're asking for some answers that are already here.

I have looked over the thread. I'm not super comfortable because the posts relating to the single unit are pretty tentative and the stuff that seems like they have it all figured out is related to custom pcb for 4 units. There was atleast one post with circuit designs I ddn't understand for what seemed like multiple things all on the same drawing and piecing it together to make a unit to just plug into the usb-c comign off my fan, leech power to run and control the fan isn't something I can point out how to do on here with high confidence.

 

[formularacer]

I have looked over the thread. I'm not super comfortable because the posts relating to the single unit are pretty tentative and the stuff that seems like they have it all figured out is related to custom pcb for 4 units. There was atleast one post with circuit designs I ddn't understand for what seemed like multiple things all on the same drawing and piecing it together to make a unit to just plug into the usb-c comign off my fan, leech power to run and control the fan isn't something I can point out how to do on here with high confidence.

If you want to do this there is a learning curve.
https://forum.arduino.cc will help you if you want to learn, they act like teachers if you put in effort and try and post by forum rules code in Code in Code Tags. But very helpful in all areas of electronics. If your inclined there is a section on ESP32 code get posted there are links to other pages where people have listed projects with hardware as well. I am watching that forum and trying to get better with my C++ coding and the electronics knowledge is really impressive.
If you ask for someone to build it there is a paid section for job work.

 

[ocs]

Hey guys, finally got my esp32 properly controlling my 6" AC Infinity Cloudline EC motor fans and figured I would lay it all out for you. As the title suggests I'm an idiot and just getting back into electronics, so be kind if i'm off on terminology haha. Most of the hard lifting for this stuff was not done by myself. Big thanks to the posters in the following threads that put me on the right track. Just had to have a few bowls to make it all come together

Particular thanks to @Kervork and @juanmaria of whose images I will most graciously borrow for this post.

Cloudline AI-CLS6 (S6) PWM control with RPI

After seeing another users mods I bought one of these fans because I need exact control over air flow. In this case I'm connecting a software pid controller to the fan to maintain temperature. Hotter it gets, faster the fan goes. Much to my surprise the wiring was nothing like depicted...

rollitup.org

DIY EC Fan controller?

Can anyone confirm whether 0-10v pwm is the standard for EC fan speed control? I'm in the market for an EC fan. Probably go with a Mountain Air 8in, as that's what's best available locally. It comes with a basic speed controller, but I'd like to craft up something with more flexibility. I...

www.rollitup.org

How I hooked up PWM singals to ACInfinity Cloudline T6 and Hyperfan 8" from an Open source Software

I thought I would share this info for the RUI comunity. For literally a couple of dollars I am able to control both T6 and Hyperfan Gen 1 8" independently. This is easily done by "intercepting" the PWM signal to the fans. Check the pictures to see how stupid simple this is. For the hyper fan...

www.rollitup.org

For starters, this guide is for the EC motor cloudline fans, you can quickly determine which one you have by opening the panel and looking at the wires, if you have a 7 wire connections, you're good. 4 and you have the other DC motor. Other guides cover this I'm sure. Not 100% sure if this method will work or not. YMMV

We will be using ESPhome on the esp32 with home assistant controlling the fan. Won't be covering automation at this time because that part is next on the figure this shit out list. Assuming you have esphome addon configured and working in HA.

Parts required.
esp32
MOSFET Trigger Switch Driver Module x how ever many fans
pc817 optocoupler x how ever many fans *
100ohm resister x how ever many fans *
4 pin male molex connector x how ever many fans **
breadboard
various jumpers

* not 100% sure whether an optocoupler is required for the pwm circuit coming from the cloudline motor. I've wired it up both ways and it works both ways.
** I just molested some old PCs I had kicking around for their 4 pin molex power connectors. That's what you're looking for. The old kind of power connector.

Wiring up the fan

Here is a pic of the stock wiring diagram
View attachment 4903926

Backside of the mosfet for pin reference
View attachment 4903930

And here is my slightly modified version of Kervorks original design. For our application, disregard the fact that it's going to a pi and whatever pins. Just know that the only wires you care about are the yellow (pwm) and black (gnd). We'll get back to those on the other esp side.

View attachment 4903933

And here is a pic of it all wired up.
View attachment 4903938

Inside the panel, with it oriented like above, disconnect red, yellow and black wires on the right hand side. The 3 bottom right wires in this pic. Run the red wire to VOUT+ on the mosfet, run the yellow wire to VOUT- on the mosfet. I made a jumper from the ground wire on the terminal block, connected it and the black wire to gnd pin on the mosfet. Only had white hookup wire, but you can see the ground pin on the mosfet has 2 wires coming out of it. Make sure you're jumpers are long enough so the mosfet will tuck into the corner nicely. I dabbed some hot glue on the live points on the backside of the mosfet pcb.

Leave the fan aside for bench testing or roll the dice and seal er up!

Wiring up the esp32

Depending on if you want to run an optocoupler or not, the esp side is pretty dead simple. You just need to make sure you're working with the correct wires on the control connector coming from the cloudline.

Here is a shot of the 2 wires you will be using from the cloudline, from the female side we will be providing from a pc or whatever you have.
View attachment 4903961

The yellow wire is the pwm signal from the fan, and black is the ground. Note the notches in the connector for pin orientation. Looking at the pic now, the connector housing is female, but the pins are male. So I may have misgendered this connector. I'll monitor twitter for someone educate me on gender, I'm sure it will trend hahaha Anyhow, knocking these pins out and moving the wires around is easy enough with a precision screwdriver if you're color anal.

And I managed to bang out a fritzing diagram for the esp side, don't judge, first one In the diagram I've included both a circuit with the optocoupler (yellow wire coming from esp) or just straight wired to the gpio (green wire). Of note the resister in the opto circuit is 100ohm. The dpi settings on my desktop frigged up the pin labels in the image, but red is the 3.3v rail, blacks are grounds and yellow is GPIO4 and green is GPIO5 (but use whatever pwm applicable pins you want, use esp32 pinout ref to find out what will work for you.


View attachment 4903963
And that should wrap it up hardware wise.

ESPHome and Home Assistant
* Again, assuming you know you to add esphome add on, and create a new blank esp32 device. I find it convienent to build the empty config and upload right away just to enable OTA updates going forward.

On the esp32 we will be using the ledc output to control the pwm duty cycle. That it's called ledc might seem a little off, but just know it's essentially a library for controlling pwm signals.

Edit your esp32 device to bring up the yaml editor, and paste the following

of note: make sure inverted reads true, or as it sounds 100% will be off, and 0 will be full speed. Make sure id is unique. frequency of 1000 seemed to work well enough for me.

speed_count will give you X amount of steps between 0 and 100, 10 seems to match up pretty well with what AC infinity was using before. Make sure output in the fan section matches the id from the output section. name is the display name you'll see in HA, id is it's internal name essentially.

change the pin to whatever you're using.

output:
  - platform: ledc
    pin: GPIO5
    id: intake_fan_op
    inverted: true
    frequency: 1000
   
fan:
  - platform: speed
    output: intake_fan_op
    name: "Tent intake fan"
    speed_count: 10
    id: intake_fan

validate then upload to your esp.

Now head into Configuration->Integrations in Home Assistant. You should see your esphome device listed as a newly discovered device. Follow the configure prompts for that device. When your're done you should have the name of your esp device listed in the ESPHome integrations box. When you click on it, it should have 1 device and 1 entity.

Now head back into overview, depending on how you have your areas setup the control may be in that area. I haven't done much ui massaging yet and just use the default overview with everything. I added my esp device to my tent area so it shows up in there for me

View attachment 4903980

Clicking on the fan name takes you to the speed control screen, you can't tell by the screenshot, but the slider on the bottom does in fact increment in 10s, so 0,10,20...80,90,100. And the software toggle will turn on and off the fan.

View attachment 4903981

I _think_ thats it? I've been typing a long time now and the boss just got home from work so I have to go put some time in. Let me know what you guys think I may have fucked up haha. And again thanks to all the original posters for their skills.

Hey all, this is a very long shot as this post is kinda old. But I wanted to ask 2 things:

1 - How can test test that the mosfet output voltage is proportional to the fan speed? I was able to check that with a multimeter in the original manual controller, but I just can't check the output of the mosfet as it keeps showing negative values (for reference, I tried many positions with the probes).
2 - Could you share the ESP Code, please? I did mine with help of AI and wanted to check if I'm doing something wrong, although I can see the MOSFET light dimming when I change the speed.