Maker Pro
Maker Pro

Slow down AC fan speed

wjbell

Jul 27, 2023
30
Joined
Jul 27, 2023
Messages
30
Because then it slows down all the speeds. I don't want to slow down all the speeds I just want to slow down the slowest speed. So my thinking is that there's probably the main power feeding the switch which branches off into three separate power wires going to the motor. Fast medium and slow. So my thinking is I want to break into the slow wire and do the modifications there. Is that right or no?
Which then has me thinking that the switch has to have all the necessary mechanisms in it to provide the motor with the right amount of current for the speeds. Which doesn't sound like the way it would be done. So I pretty much don't know what's going on in there. But I do know I only want to slow down the slowest speed and I think I'm going to have to tear apart the fan to figure out how to do that. *Shrug*
 

crutschow

May 7, 2021
832
Joined
May 7, 2021
Messages
832
Which then has me thinking that the switch has to have all the necessary mechanisms in it to provide the motor with the right amount of current for the speeds.
The switch likely just connects to different winding taps on the motor, so adding the capacitor in series with the slow tap should be okay.
 

crutschow

May 7, 2021
832
Joined
May 7, 2021
Messages
832
Delta Prime, your posted capacitor connection will affect all switch positions, and the TS only wants it to slow the slow position.
Thus the capacitor should be put in series with the left wire to the resistor.
 

wjbell

Jul 27, 2023
30
Joined
Jul 27, 2023
Messages
30
Delta Prime, your posted capacitor connection will affect all switch positions, and the TS only wants it to slow the slow position.
Thus the capacitor should be put in series with the left wire to the resistor.
I kind of thought that... Somehow... As a novice. Basically I was thinking that the only wire you have to break and put a capacitor in between is the slow wire.
 

Delta Prime

Jul 29, 2020
1,792
Joined
Jul 29, 2020
Messages
1,792
I know the constants.
You were the only variable kiddo!
Exactly why I posted the photo
Now you have something to reference.
Two steps ahead!
I mean people take two steps on my head! Can't you tell..
 
Last edited:

sgodblacktechy

Jul 27, 2023
11
Joined
Jul 27, 2023
Messages
11
It sounds like you're on the right track with the resistor idea. Adding more resistance could slow down the fan, but it's essential to consider the power draw and heat dissipation too. Since motors vary, finding the perfect resistor size might be a bit of trial and error.
 
Top