Computer fan lower heat stress

So i figured the tops of my plants where gettin way to much heat stress from the HPS lamp giving them life and i cant move them any lower or the light any higher so i figured i gotta extra computer fan and a 9Volt Battery, why not make a little exhaust fan to lower the heat stress. So i strapped a battery to the side of the fan, connected the wires and have it hanging right next the the lamp right between the tops of the plant and the lamp bulb. Its not super strong obviously but any help for free is worth it...ill post pictures in a little bit so you guys can throw some feedback. Id much rather have a power source from the outlet to power it, but im not tryin to mess around with wiring using currents from the house lol, i dont know how to get into the converting currents n such and the battery works. Any guess on how long a 9Volt batt. would last powering a tiny 12V computer fan?

Not long.
You can get small A/C desk fans at walmart for $5...

not right now there "out of season" thats what they told me i want to get a couple of them

Well then any idea on how to use my outlet to power the fan? Like im sure i can just wire the + and - wires to a power cord and put it in, but any idea on a way i can do that

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Originally Posted by SunnySativa

im sure i can just wire the + and - wires to a power cord and put it in,

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If you are trying to start a fire!:what::what:

I cheated a bit, and used a spare powersupply, plugged it into a motherboard, turned the pc on, then unplugged the motherboard, leaving the fans in. PSU is still running, as are the fans connected to it. made it nice and easy, as i can add/remove fans with ease.

the PSU adds a bit of extra heat, but i have it exausting out the case with anouther 12cm fan- its 69% efficient and the fans are only a few watts each.

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Originally Posted by psteve

If you are trying to start a fire!:what::what:

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Lol yea i figured

Also, i do have a power supply i took out of the computer but in order for the fan to work it has to be plug into the motherboard right? Thats a little more effort then its worth, i mean i could just put one of those desk fans in there like blowing against the wall so its not blowing directly on the plant tops, might be a little to much air.....i can make a switch ez for this computer fan, just wish i could figure out a way for my light timer to some how close/open that switch and that would solve the problem, but how lol

go to radio shack they have computer fans and power supplies for them i can actually give u the stock numbers they use

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Originally Posted by SunnySativa

Lol yea i figured

Also, i do have a power supply i took out of the computer but in order for the fan to work it has to be plug into the motherboard right? Thats a little more effort then its worth, i mean i could just put one of those desk fans in there like blowing against the wall so its not blowing directly on the plant tops, might be a little to much air.....i can make a switch ez for this computer fan, just wish i could figure out a way for my light timer to some how close/open that switch and that would solve the problem, but how lol

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I did somthing like* shorting out the green and black terminals on the PSU mobo plug with a paperclip, or somthing

*I cant actually remember right now, i upgraded to some AC fans from Do it all today

Heres the fan i speak of, and thats where i was plaining on placing it....just to give you a visual

how i powered a pc fan was i used a battery charger for a norelco electric shaver. the plug in on on battery charger fit the pins on the pc fan connector. oh i used a 80mm fan too. i think something smaller might burn out cause that 80 mm is spinning pretty fast

I have a Norelco, its not a charger you put the shaver on tho, its like something you plug into the bottom of the shaver, kinda like a cell phone charger, its 2 prongs...would that work or be to much and burn out the fan

I've rigged up a couple with cell phone chargers before, buts its important you match voltage and such. If not the sparks will fly. I know. I've learned many things the hard way.

Heres a link to how i got a PSU running without Mobo, note that you can pick up cheap PSU's for a fiver, plenty for a few fans

modtown - article - Powering an ATX PSU Without a Motherboard - if it ain't broke - mod it!

Nice, got it, where do you plug the fans into tho? Negative to any black, positive to any red?

Atkeni, thanks for the info, i got it working through my extra power supply

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Originally Posted by SunnySativa

Nice, got it, where do you plug the fans into tho? Negative to any black, positive to any red?

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just try either way and see what way the fan spins. if you hooked it up backwards it will just blow the opposite way which you dont want. it wont hurt anything but if the fan spins backwards then its hard on the bearings. you want the fan to blow back towards the plastic frame thats holding the fan in the middle. sorry for the late reply. if it seems like its spinning too fast then just hook up two fans to it. but when i had only one it spun really fast but never burnt out. when those fans go bad they will either quit working or make a bunch of noise. and that norelco thing your talking about is what i was using. it look like this>?

oops i quoted the wrong reply, go with the psu tho if its working!

Check this out.

PC Power Supply

Can someone post details (and pictures) of how to connect a CPU fan to a cell phone charger?

well in a nug shell, those tiny comp fans have 2 wires, negative and positive. First you have to make sure that the charger voltage will support the fan in the first place. If it does [look at voltage on the charger and the fan, usually says it on it] then touch the positive to the positive on the battery and the negative to the negative and it should work. I didnt try it like this but ive tested with one of those batteries that go into a hand held camcorder and it worked like a charm [i dunno if that helps you tho].

**EDIT**
Your best bet is to find a battery supply from a computer and look at the links above that show you how to wire it up that way, VERY simple, i use the comp fan in my dryin room to keep currculation..

Ok, thanks. I'll take a look.

buy the 20.00 dollar 120 volt pc fans at radio shack they dont last very long but properly mounted there pretty quiet and up 2 small chores and maybe a little safer 2(: