Modding 6 fans into one 3-pin?

[Swatdog]

Is it possible to wire six 12v fans into only one 3-pin connector OR molex? My reasoning is because I want to know if it's possible to have 6 fans at the exact RPM but only using one bus on my fan controller instead of 6?

Just wondering...

[kswaid]

I wouldn't wire 6 fans into a single 3-pin, it would probably draw too much current. 6 into a molex would work though.

[Swatdog]

Yeah I figured a molex would work, but the problem is that the molex will need to be converted into a 3-pin as my fan controller will only work with a 3-pin.

[stang8118]

Never knew you can run 6 fans off 1 molex, might rewire my setup to have all my fans running off 1 or 2 molex's. Can you still do the 7v mod with multiple fans?

[squasher]

Its not hard, just take all the leads and wire them together to one line, then do what you want with that here is what it looks like for 3
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.s are there because I can not have 2 spaces

[stang8118]

Some fans i have are 3 pin, some are 4 pin... does that matter at all?

[Swatdog]

Yes, the fan controller that I will be using (The LIS 2 Premium) only accepts 3-pin connectors on the fan bus.

[mortimer]

Splicing the fan wires together with a wire nut, three actually, and an extra wire for the eventual 3 pin connector will work. I wonder whether your fan controller provide enough juice to drive 6 fans.

[Swatdog]

Splicing the fan wires together with a wire nut, three actually, and an extra wire for the eventual 3 pin connector will work. I wonder whether your fan controller provide enough juice to drive 6 fans.

The controller is rated at 10 watts per channel. Enough?

[zip22]

The controller is rated at 10 watts per channel. Enough?

what fans are you thinking of hooking up?

power [watts] = voltage x current

i HIGHLY doubt you can put 6 fans on one channel. most normal 80mm fans use over 2 watts. if you have 120mm fans or high power fans dont hook them up to one channel. if you exceed the power the channel is rated for, it will probably destroy the circuit board.

[JaY_III]

if you exceed the power the channel is rated for, it will probably destroy the circuit board.

VERY TRUE!
If memory serves correct some of the higer end delts even had a reputation to blow fan heads on motherboards. So you might have to beef up the electronics on the fan controller to make that work

[sevendevilhell]

here's what you do. get your six fans, all with 3-pin connectors. wire the + and - wires into the molex, then take all the signal wires (all six of them) and splice them together at the end. then stuff them into the proper hole on a 3-pin connector and just leave the holes for the DC wires open. plug the 6-fan molex into your power supply, then plug the one signal wire into the 3-pin connector on your motherboard or fan controller. it will give all the fans the same RPM signal, and provide the molex power from the PSU.

it looks from the thread that that plan was beginning to come about, but it wasn't ever fully formed.

try that out and it should work provided that your controller can send enough power to all the fans to keep the RPM signal running smoothly.

[kswaid]

Yes, I think what sevendevilhell suggested would work very well for you. Just make sure to hook the fans up to a line that is not also connected to your hard drive or vid card.

[zip22]

the problem was, he was going to plug all six fans into ONE 10W fan controller. with small silent fans, that might be ok, but with larger fans, he would wreck the fan controller. fans have power ratings that range from <1W to over 20W. he could burn out the LIS fan controller pretty quickly.

[KillrBuckeye]

here's what you do. get your six fans, all with 3-pin connectors. wire the + and - wires into the molex, then take all the signal wires (all six of them) and splice them together at the end. then stuff them into the proper hole on a 3-pin connector and just leave the holes for the DC wires open. plug the 6-fan molex into your power supply, then plug the one signal wire into the 3-pin connector on your motherboard or fan controller. it will give all the fans the same RPM signal, and provide the molex power from the PSU.

it looks from the thread that that plan was beginning to come about, but it wasn't ever fully formed.

try that out and it should work provided that your controller can send enough power to all the fans to keep the RPM signal running smoothly.I thought that fan speed was controlled by adjusting the resistance (and thus the current supplied to the fan). If that's the case, your suggestion wouldn't allow for control of the fan speed.

[Borisw37]

here's what you do. get your six fans, all with 3-pin connectors. wire the + and - wires into the molex, then take all the signal wires (all six of them) and splice them together at the end. then stuff them into the proper hole on a 3-pin connector and just leave the holes for the DC wires open. plug the 6-fan molex into your power supply, then plug the one signal wire into the 3-pin connector on your motherboard or fan controller. it will give all the fans the same RPM signal, and provide the molex power from the PSU.

it looks from the thread that that plan was beginning to come about, but it wasn't ever fully formed.

try that out and it should work provided that your controller can send enough power to all the fans to keep the RPM signal running smoothly.
I dont think this will work.
The third wire is used to monitor fan's rpm, not set it. A fan just sends out an impulse
5v ......... _____
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.............|.......|
0v______|.......|_______

*ingnore the ......, the forum deletes long rows of spaces.
once every revolution. If you have more than one fan the chances of all of them running at same EXACT speed, AND being synchronized is very slim. Thus you are going to get a jumble of signals that will not be properly interpreted by the fan controller.

[Swatdog]

I dont think this will work.
The third wire is used to monitor fan's rpm, not set it. A fan just sends out an impulse
5v ......... _____
.............|.......|
.............|.......|
0v______|.......|_______

*ingnore the ......, the forum deletes long rows of spaces.
once every revolution. If you have more than one fan the chances of all of them running at same EXACT speed, AND being synchronized is very slim. Thus you are going to get a jumble of signals that will not be properly interpreted by the fan controller.

So even if the fans are being powered by the PSU through a molex, it still wouldn't work? There is no wire that handles the RPM (sets it)?

[Borisw37]

So even if the fans are being powered by the PSU through a molex, it still wouldn't work? There is no wire that handles the RPM (sets it)?
Correct. The way fan controllers work (the inteligent kind that measure RPMs) is they receive the pulses from the motor. Calculate the RPM, depending on the frequency of the pulses, and then adjust the voltage* in order to reach the requiered RPM.

*most actually use PWM (pulse width modulation, a much better way to control fan RPMs)

[Swatdog]

Well I guess I might spend some extra money and get another rheobus... How does this look?

http://www.frozencpu.com/bus-54.html

[OCFCaTalyst]

Its not possible to run different fans at the same RPM on one channel of a rheobus. If you had 6 identical fans this would work.

-CaT

[Swatdog]

Its not possible to run different fans at the same RPM on one channel of a rheobus. If you had 6 identical fans this would work.

-CaT


Well, yeah they would be all the same fans. Also, I won't have 6 fans anymore, there will only be 4.

[Borisw37]

Swatdog,
The rheobus you linked to, outputs voltage from 0 to 12v, and is rated up to 20watt per channel. It does not use the third wire to monitor the RPM, it doesnt use it for anything. You can connect any number of fans (or any other 12v devices you might want to adjust voltage on) to it, as long as the combined power consumption of all devices on each chanel is below 20watt. I thought you had a rheobus that had RPM readout.

[Swatdog]

Swatdog,
The rheobus you linked to, outputs voltage from 0 to 12v, and is rated up to 20watt per channel. It does not use the third wire to monitor the RPM, it doesnt use it for anything. You can connect any number of fans (or any other 12v devices you might want to adjust voltage on) to it, as long as the combined power consumption of all devices on each chanel is below 20watt. I thought you had a rheobus that had RPM readout.

I will... I will also be getting the LIS 2 Premium but the output wattage is only 10W instead of 20W. I wanted the 20W rheobus to control the powerful delta fans that I will be having on my radiator.

[hitokiri_808]

I have a vantec fan controller, 18w a channel and it works great for me. Its around $20 at most places. I plan on buying another one for my other comp.

[Swatdog]

I have a vantec fan controller, 18w a channel and it works great for me. Its around $20 at most places. I plan on buying another one for my other comp.

Vantec controllers are pretty good, I have a 3.5" not sure of the voltage/wattage.

[sevendevilhell]

i've seen fans with a molex connector and then a signal wire coming from it that plugs into a 3-pin and just leaves the other wires open.

if it can't set the RPM while plugged into a molex, then that would be pointless. however, i know that what you're saying is correct. so i'm confused as to why they've made fans with that sort of system. monitoring the RPM does no good if it can't be changed.

[zip22]

it is just to monitor. some motherboards require a signal on the heatsink fan plug, and you can also set up things like of a fan stops running, you shut down or an alarm goes off

[KillrBuckeye]

i've seen fans with a molex connector and then a signal wire coming from it that plugs into a 3-pin and just leaves the other wires open.

if it can't set the RPM while plugged into a molex, then that would be pointless. however, i know that what you're saying is correct. so i'm confused as to why they've made fans with that sort of system. monitoring the RPM does no good if it can't be changed.The answer is really quite simple. Think about it, one way or another, the electrical current supplied to the fan is what ultimately determines how fast the fan will spin. If there was a signal wire that could monitor AND control fan speed, there would need to be some integrated variable resistor on the fan itself. This would significantly raise the manufacturing cost of the fan, which is undesirable to the many people (most people) who just run their fans at default (full) speed. Therefore, the fan speed monitoring signal is intended for those who want to manually adjust the current supplied to the fan (via a fan controller) to achieve to desired speed, or for use by software algorithms that dynamically control the supplied current based on case/CPU temperatures.

[Ardneh42]

Well I guess I might spend some extra money and get another rheobus... How does this look?

http://www.frozencpu.com/bus-54.html


I have one of these controllers and it is great, but you can find it cheaper at jab-tech.com: http://www.jab-tech.com/catalog/Sunbeam_51_4_Rheobus_Kit__BLACK_p_2530.html

[Electron Chaser]

Vantec controllers are pretty good, I have a 3.5" not sure of the voltage/wattage.

They all put out 18 watts per channel.

Just pick one fan to hook the RPM sensor up. It will cause less problems.

If you still intend on hooking up 4 fans to one channel make sure the total wattage does not exceed 18 watts.

What fans exactly are you using? If you could post a pic of them and their connectors and part numbers I should be able to come up with a very viable solution for you.

[Swatdog]

They all put out 18 watts per channel.

Just pick one fan to hook the RPM sensor up. It will cause less problems.

If you still intend on hooking up 4 fans to one channel make sure the total wattage does not exceed 18 watts.

What fans exactly are you using? If you could post a pic of them and their connectors and part numbers I should be able to come up with a very viable solution for you.

Well, I haven't bought them yet, but I was thinking about getting these:

http://www.xoxide.com/12alcasfan.html

[mtb856]

If you splice all of the fans together into one molex, you'll still be under the max power rating of the Sunbeam (by 2W), so it should handle those fans with no problem. I'm not sure why you need to have an RPM cable attached though, none of my fans on my rheobus have RPM cables and I've had no problem with controlling them. All you're doing is varying the +5V voltage into the card using a variable resistor (or a transistor in more advanced rheobuses like the Sunbeam or the Vantec), RPMs have no effect on how well they work.

Now if you want to monitor the RPM's that's another story, and I'd just do what EC is saying.......... since they'll all be running at the same speed, you only need to keep one of the RPM cables and attach it to the motherboard or something like that. That's what I did with my Delta, I converted it to molex by taking the ground and +5V out of the 3pin and putting them on a molex connector............ then you just leave the blue wire (RPM) in the 3pin and connect it to the motherboard.

Sorry if I missed the idea of what you were trying to say, but that's the way that I understood it.

[Electron Chaser]

Well after doing some research since Xoxide's numbers didn't add up add all

.37 Amps *12 = 3 Watts HUH???

I actually found some other specs. .38 Amps * 12 = 4.56 Watts Much more realistic!!

This means the best you are going to get is 4 fans per channel using a sunbeam fan controller and only 3 if you are using a Vantec.

[Electron Chaser]

Well after doing some research since Xoxide's numbers didn't add up add all

.37 Amps *12 = 3 Watts HUH???

I actually found some other specs. .38 Amps * 12 = 4.56 Watts Much more realistic!!

This means the best you are going to get is 4 fans per channel using a sunbeam fan controller and 3 maybe 4 (But you are pushing it) if you are using a Vantec.

[mtb856]

With the Vantec, you'd be slightly over it's max power per channel with 4 fans so you'd probably end up having to run 3 per channel............ although you have 4 channels on either of those fan controllers, so do you really need to have them all on one channel? Unless you have quite a few powerful case fans, you should be able to fit all of them onto that rheobus with no problems.

[zip22]

Well after doing some research since Xoxide's numbers didn't add up add all

.37 Amps *12 = 3 Watts HUH???


i was confused by that myself. :) gotta love fuzzy numbers in advertising