midwestganja
Member
How would I go about wiring up a PC fan to use for my small mini-cube for my lowryders? I honestly dont know where to start!
Thanks!
Thanks!
How to wire a PC fan ?
- Thread starter midwestganja
- Start date
Find yourself an AC to DC adapter that plugs into the wall, look for something thats rated for 120VAC input -> 12VDC output@~500mA. These can be found on most any type of electronics or electronic chargers, if you don't have luck there I know radio shack sells them. If you want multiple fans off 1 adapter wire them in parallel rather than series since you want current dividing circuits rather than voltage dividing circuits which cause your fan to spin slower. If the fan is too loud @12V you can try using a 9V adapter or 6V, personally on some of my fans I used an adjustable adapter to get it where I want.
Here is a diagram of the most simple parallel circuit - http://people.sinclair.edu/nickreeder/EET114/PageArt/CircuitParallelConnect.gif
Basically each fan will have 2 leads (wires) the simplest way to do things would be plug your adapter into the wall (be sure not to short the leads) and then touch the ends to the ends of your fan leads. From this you'll be able to determine polarity, basically the fans will only work with the leads connected to the proper ends of your adapter. Make sure to remember which ends go to where for each fan (put tape or use a marker or something) and do this for each fan. Once you know which leads go together you can join them all up together at one spot with the proper ends of the adapter.
Basically look at the diagram and notice how all the leads on the top of the circuit go to the same point, the same applies for the bottom of the circuit. The resistors in the diagram are basically the same as a fans. Another point to mention is that you must make sure that your adapter has enough power output for your fans, each fan should have a rating on it (likely something like 12VDC@150-250mA). Add these mA figures together to get an understanding of your current draw, you want to make sure your adapter has enough power for the fans in your circuit.
The only other way to wire the fans would be a series configuration, this is basically joining all the fans negative to positive then the 2 left over leads go to the voltage source. When you wire things up this way you get voltage drops, the fans spin slower with reduced voltage which is often not what you want.
I'm sure you can wire fans to a PC power supply but it likely requires some tweaking, without a multimeter I wouldn't mess around with it and since your understanding is limited I'd suggest sticking to the very simply wall adapters. My suggestion is to try and find one with a high current rating, I found one at RadioShack/The source that was rated for 750mA - enough for 3-4 fans paralleled depending on their ratings.
Basically each fan will have 2 leads (wires) the simplest way to do things would be plug your adapter into the wall (be sure not to short the leads) and then touch the ends to the ends of your fan leads. From this you'll be able to determine polarity, basically the fans will only work with the leads connected to the proper ends of your adapter. Make sure to remember which ends go to where for each fan (put tape or use a marker or something) and do this for each fan. Once you know which leads go together you can join them all up together at one spot with the proper ends of the adapter.
Basically look at the diagram and notice how all the leads on the top of the circuit go to the same point, the same applies for the bottom of the circuit. The resistors in the diagram are basically the same as a fans. Another point to mention is that you must make sure that your adapter has enough power output for your fans, each fan should have a rating on it (likely something like 12VDC@150-250mA). Add these mA figures together to get an understanding of your current draw, you want to make sure your adapter has enough power for the fans in your circuit.
The only other way to wire the fans would be a series configuration, this is basically joining all the fans negative to positive then the 2 left over leads go to the voltage source. When you wire things up this way you get voltage drops, the fans spin slower with reduced voltage which is often not what you want.
I'm sure you can wire fans to a PC power supply but it likely requires some tweaking, without a multimeter I wouldn't mess around with it and since your understanding is limited I'd suggest sticking to the very simply wall adapters. My suggestion is to try and find one with a high current rating, I found one at RadioShack/The source that was rated for 750mA - enough for 3-4 fans paralleled depending on their ratings.
midwestganja
Member
Thank u! 
Quazi
Member
The Shack also sells AC cooling fans made for electronics.
They are a bit thicker/heavier (which means they feel more well built) and more expensive than the DC fans, but they are quiet and push a lot of air:
I use that to cool 6x23W of CFLs and it does a great job. It was around $20.00 if I remember correctly. You'll spend more than that on a DC fan + adapter. I just picked up a fan and a little extension cord for $3.99 that was cut and wired to the fan.
Since it's AC already, you don't have to worry about complicating things with an adapter.
Just an idea if you plan on going this route.
-Q
They are a bit thicker/heavier (which means they feel more well built) and more expensive than the DC fans, but they are quiet and push a lot of air:
I use that to cool 6x23W of CFLs and it does a great job. It was around $20.00 if I remember correctly. You'll spend more than that on a DC fan + adapter. I just picked up a fan and a little extension cord for $3.99 that was cut and wired to the fan.
Since it's AC already, you don't have to worry about complicating things with an adapter.
Just an idea if you plan on going this route.
-Q
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midwestganja
Member
Another good idea Ty!
Ty! 
Cannabean
Active member
Orrrr... If you have a spare computer power supply, you can run as many cheap 12v PC fans as you want. Without a computer. You just have to jump the power supply.
This can be done by finding the largest connector coming from the power supply... Next find the green wire. Now take a paper clip or a short piece of insulated wire and put one end in the whole in the molex connector with the green wire and the other end in the one with the black wire diagonal from the green. Now the "power switch" is always on. Assuming your power supply has an on/off switch you can use that to turn it on and off or just unplug it. Be safe and make sure you're well versed in how these things work before attemping.
This can be done by finding the largest connector coming from the power supply... Next find the green wire. Now take a paper clip or a short piece of insulated wire and put one end in the whole in the molex connector with the green wire and the other end in the one with the black wire diagonal from the green. Now the "power switch" is always on. Assuming your power supply has an on/off switch you can use that to turn it on and off or just unplug it. Be safe and make sure you're well versed in how these things work before attemping.
Yellowmoon
Active member
I took my spare nokia cellphone adapter and a small 2" pc fan, cut the wires + attached them and it works like a charm.
just so i dont have to start a new thread. I have a quick question.
I have a 90mm PC fan sitting here and instead of there being a red and black wire, there are 3 silver wires. Im not sure which ones need to be connected to what. Anyone have any idea? I tried a few different wires but i actuially thinki might have blown the motor in the fan.
But yeah, connecting fans to AC/DC adapers is super easy. Connect white with red and black with black. VIOLA!
I have a 90mm PC fan sitting here and instead of there being a red and black wire, there are 3 silver wires. Im not sure which ones need to be connected to what. Anyone have any idea? I tried a few different wires but i actuially thinki might have blown the motor in the fan.
But yeah, connecting fans to AC/DC adapers is super easy. Connect white with red and black with black. VIOLA!
that is a pwm abled fan, the third wire is for speed control. because they didn't used coloured wires for +/- without the socket atached to the wires you'll never know which is which. if you have the socket atached, you can look in a motherboard manual at a pwm fan socket, and you'll see which is +/-. but if it doesn't work anymore and you've used all the combinations maybe you short circuited it.
i think i might have becuase i could smell the plastic
The thing that confuses me is that it had a seperate thing of wires for the speed control switch. Usually its red/yellow/black and yellow is for speed control. This time the speed control had its own manual switch and wires. Oh well, fans are super cheap on ebay and you can get them in bulk for the price of 2 fans at Frys or the such.
Thanks for the help though, ill see if i still have my motherboard manual and ive it another shot after class.
The thing that confuses me is that it had a seperate thing of wires for the speed control switch. Usually its red/yellow/black and yellow is for speed control. This time the speed control had its own manual switch and wires. Oh well, fans are super cheap on ebay and you can get them in bulk for the price of 2 fans at Frys or the such.
Thanks for the help though, ill see if i still have my motherboard manual and ive it another shot after class.
mrcheezy503
Member
excelent
Quazi
Member
I thought I'd just add a bit to what I said earlier after another member was asking me questions about the fan that I have in my cabinet.
There are PC fans that have the 3-4 pin connectors that are made to be attached to a power supply. These are DC fans most of the time meaning a converter is needed (such as a power supply or the aforementioned AC/DC converters).
There are also "cooling fans" (not PC fans) that the Shack sells. They run in 120VAC and they are very powerful and very quiet. That's what I have installed and love it. These do not require a converter. You can simply splice an extension cord, connect the wires, and plug it in.
Here's a link to the product in question:
http://www.radioshack.com/product/index.jsp?productId=2103787
Anyway... just thought I'd add that info to clear up any further confusion.
-Q
There are PC fans that have the 3-4 pin connectors that are made to be attached to a power supply. These are DC fans most of the time meaning a converter is needed (such as a power supply or the aforementioned AC/DC converters).
There are also "cooling fans" (not PC fans) that the Shack sells. They run in 120VAC and they are very powerful and very quiet. That's what I have installed and love it. These do not require a converter. You can simply splice an extension cord, connect the wires, and plug it in.
Here's a link to the product in question:
http://www.radioshack.com/product/index.jsp?productId=2103787
Anyway... just thought I'd add that info to clear up any further confusion.
-Q
Last edited:
forester
Member
Thanks RJE231, you gem! I found an example a bit later after dicking around through the forums but this was a great help! Beautiful thing about IC is that no matter what you have problems with you can always find someone who has done it before and can tell ya how it should be done (I also found out how I can run the lot of the PC lead and powerstrip).
So I've asked some friends and searched this forums trying to figure out how to wire my fans to some old adapters I have lying around.
Based on what I know, there are 6 possible combinations for having a computer fan with a red, black, and yellow wire; as well as an adapter with a positive (non-marked) and negative (white marked) wire.
The combinations are as follows:
1. negative red + positive black
2. negative red/yellow + positive black
3. negative red + positive black/yellow
4. negative black + positive red
5. negative black/yellow + positive red
6. negative black + positive red/yellow
I've done this numerous times and each time with a 12v adapter and a 9v (the fans require 12v but I've heard that having less v just means it will run slower) and each time it hasn't worked at a all.
Can anyone help me? Are there any alternatives?
Based on what I know, there are 6 possible combinations for having a computer fan with a red, black, and yellow wire; as well as an adapter with a positive (non-marked) and negative (white marked) wire.
The combinations are as follows:
1. negative red + positive black
2. negative red/yellow + positive black
3. negative red + positive black/yellow
4. negative black + positive red
5. negative black/yellow + positive red
6. negative black + positive red/yellow
I've done this numerous times and each time with a 12v adapter and a 9v (the fans require 12v but I've heard that having less v just means it will run slower) and each time it hasn't worked at a all.
Can anyone help me? Are there any alternatives?
yellow is speed control.
red is usually positive.
adapters usually have the positive wire marked.
is the fan doesn't work it might be burnt.
also you should check the adapters if the fans do work on another power source.
how many amps or miliamps the adapters have?
red is usually positive.
adapters usually have the positive wire marked.
is the fan doesn't work it might be burnt.
also you should check the adapters if the fans do work on another power source.
how many amps or miliamps the adapters have?
The fans are brand new, so I don't think they are burnt. I literally opened the package and stripped it to wire it to the adapter and they didn't work.
One 12v I have has 1.25A and the other is a 12v with 1.0A.
Try to connect them to a cell phone charger or another adapter (just be sure to be rated lower than 12v 1000mA / 1Amp) without cutting the adapter connector.. (just connect the wires to the charger connector)
They should at least make a slight noise even if the current is not enaugh to rotate the cooler.
I guess your adapters might have a problem. Also, maybe putting current through the speed control wire (yellow) burnt the brand new coolers..
Good luck!
They should at least make a slight noise even if the current is not enaugh to rotate the cooler.
I guess your adapters might have a problem. Also, maybe putting current through the speed control wire (yellow) burnt the brand new coolers..
Good luck!
