4028 PWM not working
So I wired my Delta 4028 fan as shown in the 4028 guide with red to the top fan pin at 12v, black to PB11 heater pin, and the PWM pin to the FAN0 PA8 pin. I can turn the fan on and off fine, but while on it is always at 100% no matter what I set it to on mainsail. I tried the 25khz and 100hz cycle but neither worked. Is there possibly something wrong with my FAN0 pin or is it possibly something else?
7 Replies
sunny-green•16mo ago
conscious-sapphire•16mo ago
I am guessing you are using an Octopus board. aren't you missing a black wire (ground) next to the red?
sunny-green•16mo ago
No, that's going to the heater pin down by the blue wire.
conscious-sapphire•16mo ago
tried to duplicate your problem. At 0 it does not run but at 1% it blows 99% and dies down the higher the number gets at 255 it stops. exclamation mark or not it doesn't make a difference.
[fan]
pin: !fan_part_cooling_pin
enable_pin: PB11
cycle_time: 0.00004
might be silly but have you tried the yellow wire instead of the blue?
sunny-green•16mo ago
I have not, but I could. Weird thing is that my fan won't even do that reversed scale. It's always 100% no matter if it's 1% or 100%, which now that I think about it might be because it's the wrong wire.
Yes, that was indeed the problem. Thank you. Apparently the yellow wire on the delta 4028s is the pwm wire and the blue is the tach wire for some reason...
conscious-sapphire•16mo ago
Glad to be of some help 🙂
This just saved me with my Deltas. thanks!