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FEATURED Building PWM Controller for 4 wires PWM fan

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Yeah, but what about on start up? will they pull more?

And Would 260 CFM in push be much greater than two Panaflos 114 CFM in Push/Pull.

I guess I could just get one first and see, I tend to think the Extra Fan might just be Overkill and would not really net any real benefit.


If not thought of already why don't you set the power on voltage to come on gradually, so there is no surge of power...

A programmable voltage regulator maybe?
 
Ok, so the fan in settled. Do you see any point in two? Push/Pull?
Dude....trust me, one is plenty ;)
If you want to add a second, use it as the case exhaust behind the VX :thup:
And Would 260 CFM in push be much greater than two Panaflos 114 CFM in Push/Pull.
A single 260CFM fan will eat those Panaflo's for breakfast ;)
One more thing, don't buy those components yet, I'm currently tweaking that circuit to make it more powerful and will provide better & stronger PWM signal, and prolly with this single circuit alone, this fan controller can drives 50 PWM fans. Miah should be interested in this too. :D

Give me a day or two, I will post the new circuit here and give the complete shopping list for that circuit.
You got my attention mud :D
Ok, fan is on the way. Should be here by Friday.
The San-Ace right?
 
Yeah, Miah, the San Ace. I have already been running the Panaflo H1BX's X2.

I need Moah Powah! Moo Haa Haa Haa!
 
Adjustable PWM Controller for 4 wires PWM fan (not applicable for 3 wires fan)

PWM fan (4 cables) Controller circuit with adjustable duty cycle from 2% up to 98%.
This one actually is the same as Nidec's circuit above, its just I added PWM signal booster to cope with fan that might suck higher power than normal at the PWM out that will degrade it like Brutal's Sanyo Denki fan case.

1652288171256.png
Note : Actually that 556 IC is just two 555 ICs packed in one IC body, you could use two separated 555 ICs too,


Another version for purist who wants pure 0% (zero percent) up to 100% duty cycle. All connections to power (molex) and fans are the same as above circuit.

1652288178305.png

This circuit has an additional IC called comparator, it uses LM311, you can change it with other popular comparator ICs like LM393 or LM339, although the pins assignment are different, just map them accordingly.

Update 14th Aug 11 :
Single controller with 2 normal outputs for normal pwm fans and the other one for the inverted pwm fan.

http://www.overclockers.com/forums/showpost.php?p=6935139&postcount=834

1652288192773.png
attachment.php


Update 9th Aug 11 :
Kick Start Add On
Read the detail explanation here -> http://www.overclockers.com/forums/showpost.php?p=6931080&postcount=822

Also a demonstration video of Kick Start mechanism in action -> http://www.overclockers.com/forums/...ires-PWM-fan?p=7116335&viewfull=1#post7116335

1652288203433.png
attachment.php

Both circuits are using PWM frequency that is set according to FormFactors standard for 4 wires PWM fan -> http://www.formfactors.org/developer/specs/4_Wire_PWM_Spec.pdf
 
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Above circuit actually still the same as the one from Nidec, its just I added additional amplifer (aka Inverted Schmitt Buffer) to beef up the PWM signal so it will be clean and powerful enough to drive multiple PWM fans.

Actually that IC is just the same IC TLC555 but it has two of them inside one package.

The TLC556 cost just bout $1.26 from Digikey -> TLC556 at Digikey

Components like resistors, capacitors and potentiometer should be dirt cheap.

Other components which I think quite important that are not in the circuit are those connectors, I think you need lots of them especially male 4 pins for the fan and 4 pins female or 3 pins for mobo's header with 3 pins and cables since you will need to for splitting them like these below :

1652288257447.png
 
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All my Headers are 4 Pin. Its a Asus Maximus III Formula. The board can run 84 watts of fans, so hooking them all up there is out of the question. Going to run molex for the power, and then split off the RPM/PWM signals to the Mobo.
 
Brutal, just a reminder to purchase the 680 pF for that C1 cap too, since that mini beast of yours is working at 16Khz PWM frequency, although it doesn't hurt to try it at the standard 25Khz.
 
I think I am missing something. From the schematic, I don't see the "control" portion of this circuit. No knob or potentiometer. How will I change it from 2-98% is it a programmed value? I am missing something.

Looking at the TLC556, it is a digital programmable product? CMOS timer? Does it work in conjunction with the Motherboard? Am I supposed to use this if I don't have on board PWM from my Motherboard?
 
I think I am missing something. From the schematic, I don't see the "control" portion of this circuit. No knob or potentiometer. How will I change it from 2-98% is it a programmed value? I am missing something.

Sorry, I thought you recognize the electronic symbols, its the P1 with 100K value, that is the potentiometer, -> Potentiometer Wiki , look at the illustrated picture and the corresponding symbol below it, the one at the circuit is the US version.

Looking at the TLC556, it is a digital programmable product? CMOS timer? Does it work in conjunction with the Motherboard? Am I supposed to use this if I don't have on board PWM from my Motherboard?

I thought you're going to build the controller from the 1st place ? No, you don't have to use this if you're happy with the on board PWM control (4 pins header) in controlling your PWM fan.

The purpose of this particular fan controller is to give you an option if the mobo control feature is somewhat limited or not working as you expected. It works independently from the mobo.

With this you can manually adjust the speed thru the pot just like an ordinary fan controller while maintain accurate speed reading thru mobo's header, but this one is for driving/controlling PWM fan ONLY, and capable of driving many of them at once with only single fan controller regarding their power consumption, since it supplies only the PWM signal (low power) while the fan itself draws power directly from the PSU.

The accurate speed reading even slowed down to minimum and significant power efficiency when altering the fan's speed are the primary advantages of PWM fan (4 cables) compared to legacy 3 cables fan. When it comes to power efficiency, running monster fan or lot of fans really matter, especially the PSU is somewhat near it's power capacity.

You don't have this luxury when using ordinary fan controller/rheostat since they're simply burning the excess power into heat and passing the rest to the fan to slow it down.

About that IC, you're right, that is the legendary 555 timer, the 556 is just two 555 chips packed inside a single package. The one I suggested TLC555 is the CMOS version, there is other bi-polar version with the part number NE556, just use the CMOS version as suggested.

In your case, wait until you tested it directly from mobo, and if you're not happy with the mobo's controlling mechanism, then its time to build it, thats all.

.​
 
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Oh, your P makes more sense now. In automotive a potentiomter or a variable resistor looks more like the one on the right. In all honesty I couldn't see the tiny green arrow next to the resistor part. :[

wiringdiag.PNG


I followed the whole thing except I was looking for a poti, so I figured since I couldn't see it, that maybe it was programmable in some way. I was going to try out my motherboard because asus has the ability with software to step like 10 levels from 10% up to 100%, but 10% may not be low enough, so I may end up using the controller, especially if I have more than one fan. This first one is an experiment.

Don't forget that most automotive technicians never go past the BFM (Black F------ Magic) Boxes. I understand the use of most electrical components partially because I learned automotive in Germany, where the combine Automotive Mechanic and Automotive Electrician into one field and partially because I have a knack and desire for all things electrical. As a tech, we typically see something like this.

wiring%20example.PNG


Fairly simple wiring diagrams. Rarely do I need to know anything other than the resistance of a sensor or how much voltage there is. We use CAN data bus and some of the older cars use serial data, but for the most part after checking for power, ground and communication, we are done (change out the module). Trying to explain to some of the guys that I work with on HOW a Blower Resistor works is like explaining rocket science. Its sad really. But they are "Mechanics" I am a Technician.
 
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Brutal, great to know that :thup:, now if you have any further question when you're going to build that circuit, just ask, I will try my best. ;)
 
Ok, I recieved the Beast today. The Post Office put the box in my Mailbox from behind (apartment type mailboxes) and I couldn't pull it out of the front. I had to tear the box up to get it out.

I was not aware, or didn't pay attention that this does not have a connector, so I will have to solder on the connector. I will probably need clarification to the colors of the wires because they are different on my Xigmatek PWM fan, and I just want to be sure. Mudd or Bing, your assistance will make my job easier here.

I want to wire the power directly to a Molex Connector and wire the PWM/RPM to a 4pin Header for Motherboard control first. We will see how that goes until I can put together a PWM Controller.

Here are some pics. Wire colors are Black-Red-Yello-Brown.

DSCN0549.JPG


DSCN0550.JPG



DSCN0553.JPG


DSCN0551.JPG


DSCN0554.JPG
 
I just want to say, I am scared of installing this F-ANIMAL.
:chair:

LOL :D You should be, currently that is the most powerful 120x38 mm 12 volt fan in the world that money can buy. ;)

Now, the wires assignment :

  1. Black (Negative) -> Molex (Black wire)
  2. Red (Positive) -> Molex (Yellow wire), this is +12 volt line.
  3. Yellow (RPM Sensor) -> Mobo fan header at Speed sensor (3rd pin)
  4. Brown (PWM Control Signal) -> Mobo fan header at PWM signal (4th pin)

The 4 pins mobo header, from Right to Left, the pin 1 right most is (Negative), 2nd -> Positive, 3rd -> RPM sensor and 4th -> PWM (left most).
Pin 1 and 2 will be left un-connected since it will get the power directly from the molex, only need to connect at the 3rd and 4th pin.

1652288387756.png

As usual, before powering it up, verify and re-check again the wire connections.

Suggesting if you have spare fan grill, install it, that fan is finger chopper, becareful.

Expecting to hear your result using this fan on VX at max speed compared to your other sissy fans. :D
 
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Lol, I hope I don't loose a finger. Thank you for the clarification. I will try to get it hooked up tonight.
 
Brutal, that's why I also ordered some wire fan guards with the Big Beast Denki. I refuse to run it unless I have fan guards on it on the suction side especially. You won't believe the amount of suction the fan has, believe me. Anything you have messed with until now is just a tinker toy piece of trash compared to these fans.
 
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