Proform brushless cooling fans?
Turbo LS Miata, rear mount radiator. 105amp alt.
https://www.ebay.com/itm/26405702562...BlBMUIqF_db-Yw
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And yeah they move a **** ton of air when they're on. I'm really hoping these work out..
And yeah they move a **** ton of air when they're on. I'm really hoping these work out..
ugh. Not good for me to hear. I like in the super hot south Louisiana. I can’t have fans leave me stranded. I wonder if I should request a set of updated fans too. I don’t want to take any chances.
but yea, the amount of air it moves is unfukinbelievable! If these work out, I don’t see it having any issues over heating
odd thing is in the instructions it states it’s not pwm compatible with anything else but its own controller. Hard to believe that when it’s just a pulse and full power is just sending full voltage to the green wire. I wonder if their controller actually puts out variable voltage instead of frequency. If that’s the case, I could possibly incorporate two speeds. I’m going to add a resistor to the green wire and see what happens.
Last edited by Kfxguy; Jun 12, 2024 at 09:52 PM.
but yea, the amount of air it moves is unfukinbelievable! If these work out, I don’t see it having any issues over heating
odd thing is in the instructions it states it’s not pwm compatible with anything else but its own controller. Hard to believe that when it’s just a pulse and full power is just sending full voltage to the green wire. I wonder if their controller actually puts out variable voltage instead of frequency. If that’s the case, I could possibly incorporate two speeds. I’m going to add a resistor to the green wire and see what happens.
I feel you, I'm in SC. It's blazing hot here right now. They're about to recall all of them if I'm not mistaken. So I would just check back at the end of the month if you don't have issues before then. Assuming you only bench tested and haven't ran them on a hot radiator yet? That's when they shut off. Sales rep said they ran one for 8 hours straight but never tested them on a hot radiator. Which sounds kinda sus 🤷. Idk though. I asked about why the controller says pwm, if they're not pwm capable. He said he didn't know why that controller even says that on it because it just controls the duty cycle. I asked if I could still control it through the Holley, and he Said as long as it's over 110khertz it "should" work. I thought about the resistor thing too. Interested to see how that would work.
I forgot to try the resistor last night but if it’s varied in hertz, I may need to come up with something else.
idea. Get the controller they sell. Install it, turn the speed down some on it. Then use a relay to break the circuit to the green wire and return the green wire to full 12v for full speed. You’ll need a 2 speed circuit for this which my gto has 2 speed fans. Little rewiring on my part and I think I can do it that way if the resistor doesn’t work. If I’m not mistaken, pwm just makes it see a lesser voltage.
I found this:
PWM meaning is effectively chopping off parts of the waveform to reduce the average voltagewithout affecting the base frequency of the signal. Increasing the period when the voltage is 'off' reduces the average voltage, hence the power.
pwm in our context is similar but is a square wave rather than sine wave and the frequency can be whatever we want it to be. some devices care, some sorta care. i have a device that i designed and sell that just needs anything more than about 150hz and it calcs the duty cycle from there. the duty cycle is what controls the 'amount of power' which is the percent of time on vs time off. theres no negative voltage like in ac. the frequency usually is driven by what you are powering. if its just a signal to another controller, its less important than if youre dimming a light or slowing down a fuel pump or controlling a waste gate solenoid.
for a brushless motor per the context of this thread, its just a signal to the internal controller that handles the current, so anything that makes a low current, (most likely) active low square wave will work. i have one of those boxes from ebay that i posted about earlier. its less than $10 and works great and is literally the exact piece proform is selling for $40.
Green Wire: Only for use with PROFORM mul>speed digital controller, part no. 67039 (op>onal) OR wire it
in with the 12 Volt (+) wire. DO NOT REMOVE THIS WIRE, IT MUST BE USED IN ONE OF THE TWO WAYS
MENTIONED ABOVE.
and
THIS FAN IS NOT COMPATIBLE WITH PWM VARIABLE SPEED CONTROLLERS
what they mean by pwm variable speed controllers would be one you use with a typical DC fan like the C6/Fusion controller we have a big thread about here, which are made to pwm the full load of the fan motor. these brushless fans have their own controller like that built in.
the green wire is a signal pwm input with a pulldown resistor meaning it internally grounds itself and needs a positive 12v signal (sorry terminator x dudes) to activate. either a +12v pwm (square wave) signal at 110hz or just straight 12v for 100% on.
pwm in our context is similar but is a square wave rather than sine wave and the frequency can be whatever we want it to be. some devices care, some sorta care. i have a device that i designed and sell that just needs anything more than about 150hz and it calcs the duty cycle from there. the duty cycle is what controls the 'amount of power' which is the percent of time on vs time off. theres no negative voltage like in ac. the frequency usually is driven by what you are powering. if its just a signal to another controller, its less important than if youre dimming a light or slowing down a fuel pump or controlling a waste gate solenoid.
for a brushless motor per the context of this thread, its just a signal to the internal controller that handles the current, so anything that makes a low current, (most likely) active low square wave will work. i have one of those boxes from ebay that i posted about earlier. its less than $10 and works great and is literally the exact piece proform is selling for $40.
resistors did not work. Not surprisingly.
edit. Just ordered one. Be here Sunday
Last edited by Kfxguy; Jun 14, 2024 at 08:26 PM.













