Power fans in Pc grow box

Hi guys, was just struggling to power the fans on my pc grow box I am in the process of making.
I've read around to use 12V cellphone chargers, so i grabbed a couple from home but they were all 5V and didnt do anything.
So im most likely going to buy these.. http://www.tradetech.co.nz/shop/Consumer+&+Miscellaneous+Products/AC+Output+Power+Adaptors/ADP12CAC20.html?__utma=1.962010498.1369827705.1369827705.1369827705.1&__utmb=1&__utmc=1&__utmx=-&__utmz=1.1369827705.1.2.utmccn=(referral)|utmcsr=tradetech.co.nz|utmcct=/shop/Consumer+%26+Miscellaneous+Products/AC+Output+Power+Adaptors.html|utmcmd=referral&__utmv=-&__utmk=52295466

Can anyone confirm if these will power my fans as I dont want to make a bad purchase, or maybe someone could link another option to purchase that is cheap aswell and offers shipping overseas.
Any help will be appreciated!
Thanks!

hey Allseasons, I think that adaptor would be fine, I have tried a 9v adaptor but the adaptor felt quite warm to the touch, I shelved that 1 and ended up using a 11v adaptor and it works fine, u will be able to wire up both fans to the same adaptor, hope this helps, good luck and happy growing.

i am currently using a power supply from an old Jazz drive (old school external disk with 12v and 5v) i think any external hdd power cube should work. you might have one lying around
for fans i steal them from old computers
Are you in New Zealand?
I had to ask because of the input voltage on the power supply you have linked
one question
how many fans? and what current rating?
if you are going to run multiple fans? you'll need to add up the current rating and try to match or exceed that rating on the power supply
exmp. 3 fans 300ma each 900ma that power supply you have linked will probably run those fans for a while before the power supply melts
you would want at least 1000ma or 1 amp.

If you have an old PC power supply that you don't plan on using in a computer again.....on the big 20 or 24 pin plug, find the green wire and cut it in the middle....then do the same with any of the black wires going to the same plug. Splice them together and it'll turn on the power supply. For 12 volts you want the yellow and black leads on the 4 pin connector....or just buy a PC fan with the molex plug and plug it into the power supply.

I just use one of these. It does the job fine.
I picked up a bunch in a £1 shop, never had any problems with them.
Plus you can turn the voltage down to slow down the fan a bit, should you want to.

Hi,

Im building a pc grow box, have done the lights and now onto the ventilation.

I have 2 size 120mm fans, and 5 or 6 size 80mm fans and one 40mm one too i think.
Im not sure which combo to use for exhaust:

1) 3 size 80mm fans OR
2) 1 size 120mm fan?

Question 1: Are 3 medium fans more efficient than 1 large(r) fan?

I cant tell the rotation speed but i gather that the Ampage on each fan, is an indication of its max rotation speed, right?
If so, should i use a 0.27A fan rather than a 0.12A one?

Question 2: Should i use fans with higher amp?

Powering the fans:

I understand that my charger amp rating should be higher than my total amp for all fans connected. E.g. 3 fans at 0.12A = 0.36A total; would need a charger with a rating of at least 0.40A (400mA).

Q 3: Is the above correct regarding the amp etc?

Now for the voltage. Fans are at 12V. Charger is at 5 or 7 volts (have a few phone chargers lying around the hse).

Q 4: What voltage should my charge have?

Q 5:What is the effect of using a lower voltage than 12V?

Q 6: As long as my charger's amp rating exceeds my total fan amp rating, does it matter what my charger's voltage is?

I apologise if my questions seem stupid or if i used the wrong terminology. This is my first grow and i really want to get it reasonably right (i am dying for a decent herb since moving in a country with extremely poor supply of quality cannabis).

I have seen quite a few comprehensive and helpful threads and therefore joined this forum to first get advice and hopefully give some advice too at some point.

So thanks in advance for any replies.

One.

J

If you're using PC fans, any 12v adpater will work. You might be able to use something with lower voltage but then the fans won't go full speed. If I remember right general rule of thumb is that each fan will draw about .1 amp each.

Dragon311 said:

If you're using PC fans, any 12v adpater will work. You might be able to use something with lower voltage but then the fans won't go full speed. If I remember right general rule of thumb is that each fan will draw about .1 amp each.

Click to expand...

Thanks! I will use the 12V adaptor (reason I wanted to use a lower voltage adaptor is only because the 12v adaptor is huge compared to the small phone adaptors on 5v, size matters in a pc grow case I guess...

As for the amps, the 12v adaptor goes up to 1250mA so I'll be fine for the fans as they run on 120mA or 160mA...

Thanks a lot for the quick reply!