Possible to run PC case fans off mains?

[gramin]

I have some PC case fans that I'd like to use for a cabinet grow. With some as intake and outake. Obviously I don't want to have them running off batteries that I'll have to replace all the time.

 

Alternative is to use an old PC power supply and short the pins on the motherboard connector to turn the PSU on. The ideal way would be to have them running from the mains somehow that's safe and secure.

 

Any ideas?

[stonerweed]

do you mean one of these fans

 

you can connect them upto the mains but you need somthing like an old 9v or 12v fone charger just snip the end off and join the wires

Edited August 13, 2010 by stonerweed

[gramin]

I can find some old phone chargers easily.

 

Can I run two fans on the one charger or is that pushing it?

 

How do I tell which is Pos+ and Neg- on the phone charger wires? I have a meter thing I can use but I'm not a pro at it...

[stonerweed]

well when i wire them up it dosent matter what wire is pos or neg i just joined them up and it worked i wouldent try 2 on one charger

[gramin]

The 120MM fan I want to use is 12V 0.06A.

 

I have heaps of phone chargers to use but none of them are 12V. The closest I have is 5.8V, or 18V.

 

So really I can only use the 5.8V, which has a 2 wire shielding with one in white, I figure the white one is black (neg) and it will join up to the black wire on the fan.

 

Will it be even worth it having the fan only getting half the volts it expects?

[JustAskSally]

If you really want to be safe, look at the mA (current) rating of the charger/adapter, and look at the usage rating of the fans, obviously if the rating is 600mA for adapter then u can run 2x300mA fans and likewise 3x200mA ect, but if you overload the power pack the chances are proabably high you will blow it up and you fans will stop (and u might trip your breaker if you have one), and this is usually not something you want to happen..

 

I believe the problem is that if you try to run say 2 500mA fans off 1 power pack thats 600mA the fans will constantly try to draw the 2x500mA(1000mA) from it and will eventually blow it up from the overload...

 

I use the adjustable (3v 4.5v 6v 9v 12v) power packs they seem to do the job well i think they have a pretty high current rating because they need to work with a range of devices....

 

 

Also just thought id mention it is perfectly fine to run say a 100mA fan off a 1000mA line (as long as its the same Voltage) because technically the fan should only draw the current it needs to run.. you just cant really do it the other way around.. Just make sute the voltages are correct and you have enough mA of power will be fine. and shouldnt really matter what polarity you run them i wouldnt think....

 

 

Good luck

Peace

JAS

Edited August 13, 2010 by JustAskSally

[gramin]

I think I might need to get one of these adjustable power things because I don't have a 12V one.

 

I guess you can get them from DSE?

[JustAskSally]

id assume you can get from dick smiths yeah... Probably also places like BigW Kmart etc. i think i may have even seen them at coles before although not so sure..

 

Probably find them cheap on fee-Bay also..

 

Hope i helped some..

Peace

JAS

[JustAskSally]

to use your multimeter (i assume that what it is) set it to 200v or something like that so u dont blow it up, pretty sure black goes into middle, red on right hand side marked (V) not (10A) just touch the two onto the two wires....

 

If you see like 012.xx.... or 12.x or whatever you have the red to red black to black if it says -12 or -012.xx (with the minus in front) you have them around the wrong way..

 

Peace

[gramin]

I found a multi Volt power supply on the DSE website for $20 bucks which does 12V @ 600Ma. Exactly what I need for the fan.

 

Shall get it tomorrow.

 

Currently drawing up some designs for my grow cabinet. It's small and compact (1-2 plants at at time, about bedside table size).

 

Having lots of fun planning all of this