Wiring up the computer Fan

A friend asked that I post how to wire up the computer fan so here it is.

It is very simple to wire this up however it may take a little trial and error to fine the right size power supply. I found one that was used for recharging a house rechargeable phone. Before you get to worried about the electric wiring you should know that the power supply is a low voltage and won't "shock" you easily and certainly would not hurt you. Your power supply should be in the neighborhood of 9 - 12 volts. Make sure the power supply is UNPLUGGED and cut the wire in half leaving as much wire on the power supply as possible. You will see two wires inside the insulation. Take a knife and separate them about 2 inches and then bare about the first 1/2" of each wire. Your power supply is ready to attach.

Next get your computer fan. It will have a plug on the end. You need to cut that plug off leaving as much wire on the fan as possible. Computer fans are different; Some have 2 wires and some have 3 wires. If yours has three wires don't worry it is simple to figure out. Three wires just means that it is two speed. You will want to run it on low speed for your incubator. Trim the insulation off all three wires and test it. Test it by connecting the two wires on the power supply to two of the wires on the fan. Don't let any of the pairs touch ... then plug it in but unplug it quickly. If the fan does not work try it a different way. If the fan runs then try other combinations until you determine which is the lowest speed. It is low voltage and won't hurt wiring it wrong for a few seconds. Just try it and unplug it quickly. For mine it was the white and red wire that gave me the right configuration.

Mount your fan with plenty room behind the fan for it to pull air through from behind. I found a little bracket and mounted mine out away from the sides. Of course you want to mounted to the top so you can remove all the wired parts as you remove the top. Find a hole for your wirse and use a couple wire nuts to connect up your wires and you are done.

I’m not the best at explaining so feel free to ask questions if I was not clear.

Mike

Thanks for posting this I'm going to try it tonight. I think I can do it my fan looks just like yours. I'll let you know how it works.

Question, lets say my red and white wires are the ones that work. What do I do with the black wire? Put one of those caps on it?

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Yep... just tape it off or cap it off. Remember you only have 9 volts or so on the whole fan so it's not a big danger. I personally just clipped it off and let it hang with the insulation on it lol

Don't do what I did; in a fit of stupidity, I plugged a 9 volt fan into a 120 volt outlet with no transformer.

Needless to say, BANG! POP! SMOKE!

I never have done this again. (And the fan was ruined)

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The third White Wire is a speed sensor not a speed controller it sends a signal which is use to report fan speed not control it. The computer would then adjust voltage to the red + and Black - wires to slow or speed up the fan

I would recommend using the red+ & black- wires and adjusting the voltage to get the desired speed

I run my LGs at 7.5v and my home bator at 9v but i already had adjustable power supplies

Maybe they are different then. I know the one I took out of the e-machine ran high off two wires and low off the other two.

Thanks for the input

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See now I have no idea what you are talking about. How do I know if I'm doing that? Will it say 9 volt on the fan? And I don't know what a transformer is. Maybe I won't do this. I haven't got the nerve up to do it. It seamed easy reading what Mike said now I'm scared. Give me a nail and hammer and I can build you anything but power really scares me.

ginbart

It's really no "problem" or danger. The "transformer is that "do-hickey" that plugs into the wall outlet like any other 110-120V AC cord......except it is a "bulky thing". It does say that it's input is 110V AC and output of 12 V (some are less , some are more i.e. 9 V or 14 V DC)

I don't recall whether the computer fans mention being 12 Volt DC (probably do)....but I think all of them are (in my experience).

When you "fool with" wiring, BE SURE everything is unplugged. Then "quickly" plug it in to "test"...when you are convinced that you have done it right. NO DANGER when things are unplugged (no capacitors involved).

It truly is a simple thing.

-Junkmanme-

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Was that meant as an insult? Just kidding!

NOPE (just kidding.)

-Junkmanme-