And your wiring is same than with arduino code, mosfet trigger on pin D1?
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I misplaced D5 with GPIO5 “AGAIN” 
Thank you so much man
I can’t believe I made my first HA project and now I don’t need help to change fan speed
I owe you one
as for frequencies:
I hear an annoying low pitch noise at high frequencies and fan Motor starts spining at 50%
at very low frequencies, like 10hz, It’s much better but mosfet’s led blink like crazy. at 1hz fan turns on and off on off
does it mean mosfet switch power like 10 times per second?
it won’t hurt the fan motor or shortens its life?
Congratulations!
Yep Hz is 1/s. Led blinks at the frequency you choose, but at higher frequency it looks like it’s just on.
Usually best results for fans are found at ~35Hz.
I thought Esp8266 PWM doesn’t go below 100, nice to know that it does.
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I tried lots of frequencies.everything below 60hz is fine, noise vise
but it rattles the desk so much that after 5mins I can’t feel my hand 
(using mouse on the desk. rattling make my hand feel numb
I never had that problem using my motor speed controler . don’t they do the same thing?
Maybe esp8266 PWM is not good below 100HZ after all. I don’t expect that 35Hz should make too much vibration, it’s commonly used for cooling fans.
Technically it’s doing the same. Probably around 20000Hz
Did you try that range, 20000-25000Hz?
Also, make sure you have the fan speed selector switch on full power!
I did. no noise but fan dosnt start turnin unless I set it above 95%, when it starts I can Lower it to 90%, anything below that and fan stops
that’s the main issue, at full speed/power, on every frequencies, fan works fine, no noise very little vibration, but I need to lower the speed, or else I get headace from too much wind
at 35hz at lower speeds I can clearly feel the vibration, at 20000hz much less rattle but it’s still there
maybe it’s better I mount the fan to the wall
please tell me what frequency is better for the fan, 35hz or 20khz? I don’t want to shorten its life span
I really can’t give you any answer. That fan is not meant to be speed controlled, so only way is to try.
Also, I don’t know the circuit the 2-speed switch has. Maybe just a diode to drop voltage.
Documentation of Esp8266 PWM gives lower range limit of 100Hz, so maybe it’s somehow misbehaving when driven lower. I haven’t experienced vibration while driving “non PWM fan” at 35Hz (Esp32).
For the life span of the fan I expect vibration not positive thing.
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Put a blob of blu-tack in each of the 4 “corners” of the stand. Problem solved 
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so far I could get what I needed, thanks to you, rest is fine tuning
considering its price I can’t imaging it’s anything more than a diode
so vibration aside, 35hz is not harmful to the motor? I thought turning on off the motor (power) constantly is harmful
I try to test different frequencies to find the least vibration
one more question
how can I set the speed by voice? I say “turn on/off desk fan” it work but not for setting the speed
set desk fan to 100%
set desk fan speed to high
set desk fan speed to max
none of them works, I get “I didn’t understand” error
I love these kinds of solutions 
if I make sure the vibration not gonna ruin the fan , I find a way to fix its position
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Let’s put it like this: Vibration for sure is not good for fan, so find a frequency that doesn’t vibrate too much. Adding the odds of Esp8266 PWM below 100Hz, I would prefer higher ones. Also, since you don’t know internals of your fan, it would be generally better to use high frequency and would also be good idea to add flyback diode across the mosfet output.
And if you fan ever dies, buy a 4-wire PWM fan for silent and precise control.
I have no idea about voice control.
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maybe I made it too dramatic
right now vibration is so low you can’t see it with eyes and you only feel it when you put your hand on the desk but to be safe I’ll be using high frequencies and I’m going to try learning about flyback diodes and knowing which one is suitable for my setup
are there anyway to fix the problem when motor doesn’t start spinning at high frequencies if you set it below 95% speed?
You can use 1n400x (or almost whatever normal diode you have on hands) and it needs to point from negative to positive.
Motor needs higher power to start spinning. You can set your code to make it start at full power.
fan:
- platform: speed
output: pwm_output
name: "USB Fan"
id: usb_fan
on_turn_on:
- fan.turn_on:
id: usb_fan
speed: 100
Later you can study esphome and make automation to lower that speed back after one second.
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Thank you
since I have no problem with that voltage reducer, is there any module exactly like that but intead of a manual potentiometre I can control the voltage with esp8622?
The problem here is that you already supposed to have it.
The potentiometer module has dual mosfet chip and rest of the circuit is to generate pwm.
The mosfet module you have should work identically except pwm is generated by Esp.
I wonder at this point if it really has genuine AOD4184 mosfets…
In theory you could even use the pot one with Esp (bypassing the pwm circuit).
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it’s a Chinese module, everything is possible
is there any simple way to test that?
you mean wiring my setup like the picture (solder GPIO5 pin to that tiny hole) I can use that module instead?
I don’t see any reason why it wouldn’t work. That point goes to mosfet gates through those two resistors. But not so easy to solder. Alternatively you could solder on one of the resistor pads:
Also you should verify the value of those two tiny resistors, you might need to put additional resistor in series with the wire.
I’m not taking any responsibility of this operation though.
Edit: do you have the “hole” tinned in your module? If you can fit a tiny wire in the hole and solder it on the backside, it would be easy job.
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I try to do that but if I need to do more steps buying and solderin restors, that’s too much for me
for now try to find the best frequency with current setup
Thank you so much Karosm, your help with patience is remarkable
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