help with fan wiring?
- Thread starter mykul916
- Start date
VictorVIcious
Well-Known Member
you will need a 120 volt ac to 12 volt dc converter, commonly avaiable as power sources for cd players, cell phone charges etc. I believe there is a description and pictures of how to wire a computer fan in the FAQ upper left hand corner of this page. VV
basically, you need one of these.
do you know how many amps the blower needs to run? you might need a pretty large power supply. look at thrift stores or yard sales maybe. or ebay. you might need one with over 1 amp (1000ma). often times computer equiptment have power supplies like this, big enough to handle your fan. have an old computer from the 90's laying around? take the power supply out of it. usually (but not always) the - wire is black and the + wire is yellow on those.
do you know how many amps the blower needs to run? you might need a pretty large power supply. look at thrift stores or yard sales maybe. or ebay. you might need one with over 1 amp (1000ma). often times computer equiptment have power supplies like this, big enough to handle your fan. have an old computer from the 90's laying around? take the power supply out of it. usually (but not always) the - wire is black and the + wire is yellow on those.
techhead420
Well-Known Member
Take your fan to Radio Shack and ask the people there what sort of adapter that you need. They'll have something in stock that'll work.
if you talk to a sales rep that actually knows something, they will sell you a power supply that will work, but at a very high price. I've built a 100 amp 12 volt power supply for less money then what they charge for a 10 amp. I've seen pictures of a few people using computer power supplies on here. that method will work well.
if you have what's called an AT computer power supply, it will have a standard on/off switch connected to it, and is cake to hook up. if you have a newer one, it's called an ATX power supply. on the biggest connector, just cut the green wire and one of the blacks and twist them together and put a wire nut or some tape on it. that will turn it on.
I just bought two 80mm fans from Radio Shack. On the back it says started voltage - 6v/7v max and power input 1.2w. Can I use a cell phone charger for this set up...?
really? I didn't know they sold fans at that voltage. you can try a cell phone charger. it should be enough power for 1 fan, but 2 would be pushing it. those chargers are usually something like 4.8v I think, so the fan would spin slower.
a computer power supply can be used here too. you can either hook the 2 fans up in parallel on the black and red wires (5 volt to each fan), or wire the fans in series to the black and yellow wires (6 volt to each fan)
techhead420
Well-Known Member
Yeah, that's all well and good but if this person is asking basic questions about a power supply then the chances of him building one hovers around zero.
No one can make an empirical suggestion without knowing the current rating of the fan.
techhead420
Well-Known Member
Radio Shack will have a small voltage adapter ("wall wart") that has a little switch for different voltages. I think they might call it a "universal adapter". It will have enough current to handle your fans.I just bought two 80mm fans from Radio Shack. On the back it says started voltage - 6v/7v max and power input 1.2w. Can I use a cell phone charger for this set up...?
The problem with using a cell phone charger is that depending on the load, the charger can be operating constant current or constant voltage. There's a little chip on board designed specifically for charging lithium batteries and it's a bit of a crap shoot if it'll work properly with an unintended application. Most cell phone chargers are only good for about 4.2 volts.
Here's a common example of the chip in the charger:
http://symmetrongroup.ru/extra/ns/LM3620.pdf
BigBudBalls
Well-Known Member
Is that a regulated PS? or just a x-former and rectifier. 100amp is quite a bit. I'm interested! (though typically use 24VDC)
it can be wired for 24v, but I have it wired for 12v so I can run car subs on it. that pic is before I rebuilt it. I built a rectifier bridge with 4 40 amp rectifiers. the bridge is rated at 80 amps, but I built it on a large heat sink, so it can handle anything I give it. I wired it up with bundles of 4 10 gage solid copper wires, but I think it still needs thicker wire for the internals. I've thought about regulating it, but there's no way I could fit it in the same box. it would take some massive parts.
BBB, gonna hunt me down, beat me up, and steal it from me? I'm sure you have some fun toys too!
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really depends on the fan. a 4 inch blower, my best guess would be 1 to 2 amps. the biggest wall wart you can find at radio shack might handle it. computer power supplies can handle over 10 amps at 12 volt, so it wouldn't have any trouble powering a few fans if needed, and it's pretty much a plug in and use setup. either way, computer power supply or wall wart, there will still need to be wires cut and spliced onto the fan itself.
techhead420
Well-Known Member
If you read the whole post you'll see that I was responding to some one whole bought 2 small 1.2 watt fans.
ooh, sorry, I didn't notice that. yes, that will work very well then. rep+
