The ultimate beginner's guide to PC FANS

[ScrubNinja]

mj, I noticed I lost my ambient running temp when I use the filter so shit, may have to work something out. I came up with a solution! I can wash and dry that spare kilo of carbon that I have, and use that while I wash the 2 kg that's in the filter now.

Dis, no worries bro. I don't expect people to read 20 pages so it's all good to ask, even if it's been covered. I know with myself, I can have an answer right in front of me but it just needs a little dialog with someone to make sure I don't have something twisted, before I can really be sure I understand. I'm also mindful that a lot of us have substance abuse issues LOL!

One of these days I'll tidy up the first post and collect all the fans we've come up with, and all the new developments we've all learnt. It'll be the biggest best fan thread in the world.

 

[disfunktional]

ight cool man i may try the 120 volt ac fans for shits and giggles. maybe something to add to the thread? *shrug*

 

[ScrubNinja]

Sure thing man. Surprise us with a review. I still want to do that for my fans.

 

[maryjohn]

Heya scrub, I have found that very little thickness in the carbon is required for that kind of scrubber. I had just enough to block the light and there was no odor.

 

[snuggy1955]

hopefully you guys can help me out... i just read lemons thread on the cpu power supply.
and my power supply says output 200w max...

but i got 2 fans one says 2.6 amps and the other says 19w...
so how does it go with differences between watts and amps?
i can use any amp as long as its not higher than 15 right?
and when it comes to watts. aslong as the total watts is not higher than the total output of the power supply?

is my line of thought atleast close to how this works? or am i lost.

 

[ScrubNinja]

Snuggy,

Watts = Amps x Volts
Amps = Watts/Volts

So if they are both 12v fans, use that as the volts in the calculation. So your 19w is 1.58A.

Look on the side of the PSU for a sticker like this:

On +12v I have 10A and that is the worlds cheapest PSU, lol. So you should have plenty. I would suggest (thanks to Aero's suggestion) to cut of the molexes and hardwire the fans using terminals like these (for example) :

If the PSU has multiple 12v rails, I believe it's best to put a fan on each rail too. If you have any questions, take a photo of your psu sticker first.

MJ, word, I agree. This is actually the first time I've had pure activated carbon in this design and it's the thinnest layer I've had. Haven't noticed any smell at all. You gotta hand it to activated carbon - pretty miraculous product.

Edit: the carbon I use is the super fine stuff too. I think home brewers pour alcohol through it to make a finer product.

 

[snuggy1955]

thankx alot ninja... my supply at +12v is 6A... and now i can go from there. thankx again

 

[ScrubNinja]

Excellent! One thing I got taught in my cold cathode thread (lots of PSU talk went on) is that with a cheaper power supply like mine, it's a good idea to leave hefty overhead with the amps, so the PSU is never working hard, I can't remember the percentage quoted but you seem good @ 4.18A (you will be using less amps if you slow the fans down too). There have been cases of PSUs blowing sparks out the back if they burn out. A good PSU will be protected against burning out but one like mine isn't. What you can do is buy a cheap resistor and connect it to the right wires, and then it will auomatically shut down in the event of a problem. It's worth doing if you don't have one, although I haven't yet. One thing I did do was bolt in a better fan into the PSU itself so it blows a lot more air through there. Next time I will just drop the cash for a quality supply, they're worth it. Also should be noted for anyone reading that you must take into account all the units being powered by the supply - fan speed controllers will be drawing power for example, and will count towards the amps.

 

[Norrath]

i tried this adapter out on my pc fan, it runs it very slowly, but it's okay to move a bit of air.

it works fine, but the fan is supposed to run on 12v at .3amps

the adapter is a 18v at 0.05a i figured it runs the fan alright, no problem, but on the safe side ill ask, am i asking for problems running the 12v on 18v with less amps than it says required? i know the volts, amps and watts are proportional, im just wondering if they will scale safely in this instance.

thx!

 

[ScrubNinja]

Hi Norrath. Are you sure you mean your supply is 0.05A? You sure it's not 0.5A?

A 0.05A supply is a very bad idea I think. I would buy a better adapter or fan that will supply what you need at 12v.

If you meant 0.5A, then I suspect that you're okay in regards to amps. I don't actually know for certain but the figures work out in my head. But you are very much at risk of something going wrong though, in my opinion. Overvolting fans is something overclockers do for 2 minutes while they make an attempt at the worlds fastest processor, but it's not a good idea for 24/7 constant load in an unattended growspace. Anything you can do to lessen the risk of failure should be done, and that seems to me like an invite for trouble. Hope it helps.

Also, if it's 18v, and running slowly, then yes, very much at risk, get a new power supply right this minute please.

 

[Norrath]

well the adapter says 18v 50ma, i figured throw a couple decimal places for 0.05, but ill be wrong

fan runs slowly, i just dont want any qualms:/

 

[ScrubNinja]

Well I think you're right - it's 0.05A. You have to ask yourself something. If maryjohn turned his 12v fan and power supply to 18v and it spun so fast that it burnt out in a smoke cloud....why is yours running so slowly? Is it because the power supply is about 10 times underpowered and being hammered mercilessly? Not kidding man, it sounds like an invitation for fire. A 1 amp wall wart on ebay is like 5 bucks and a speed control dial is the same. Or just buy a lesser volted power supply, or go nuts and spend a whole tenner on an adjustable voltage wall wart. You asked so I gotta be clear - really bad idea man. I hope you can work something else out. Goodwill stores, salvation army, yep, even a secondhand one is better than what you're using. Okay I'll stop now. Good luck.

 

[Norrath]

yeah ive been raping the shelves of salvation army and thrift shops around here. i bought a cd cleaner for 6$(hard to justify at the time, but id do it again if found) funny just to walk out the store throwing out the item and keeping the adapter just for its 12v 500ma..

thanks for the infos mate, it's from a phone charger i think, says 5 watts...that's really really low:|

 

[ScrubNinja]

No worries bro. I know what you mean, back in the day I used to buy external hard drive adapters from ebay just for the power supply.

 

[Norrath]

lol yeah, already using one or two of those those are awesome

 

[ScrubNinja]

Neat. If you ever want to cover every base, and if you have the room, a PC's PSU is easily the best choice in my opinion. A good one has safety stuff built in, they're metal, they supply a wide range of voltages and very high amps, they use molexes, fan controllers hook up easy, they have an inbuilt fan, they're awesome if you have a few high power fans to run.



Each of those fans is kickass (1.0A and 1.35A) and I can have 3 of them on that controller if I wanted, all as loud or fast as I need. Plus you can have multiple fans on any channel, so there are all sorts of options. All without worrying about amps and safety blah blah blah (well, not as much anyway)

I updated the first post a little, by the way. Added a few pics that have been posted mostly but I'll keep working on it. I took this screenshot from Delta's site of the 120mm axials, arranged by pressure rating. Current = Amps by the way.

Always check out the PDF of the fan you plan to get from Delta, they have great technical drawings. I know mine have solid fins attached and these are a bad idea for stealth as they only block the flow/make noise.

 

[ScrubNinja]

Maryjohn have you noticed how low you can volt your fan? I'm looking at a review of a different delta I wanted and they say 8v to 13.2v.

 

[ukpitbull]

morning all, i have read thru this thread a couple of times but i just really retarded , must be this weed !! anyway guys could sum one thake 2mins of there time to check out this link please
http://www.maplin.co.uk/Search.aspx?menuno=12760
and show me which fans i need , i need 1 or 2 to push through a homemade scrubber unsure which design yet and 1 or 2 to move air, my box will most likely be 2x2x2.5ft
thanx guys

 

[ScrubNinja]

Hi pitbull. I would suggest not getting any of those fans. They are pretty shit, dude. Find a computer modding store and you will get fantastic fans, or ebay, or whatever. There are no barriers.

 

[ukpitbull]

hi thanks for that heads up scrub, do u mean like the fans used to cool the case ?