How to convert computer fans to work with normal plug

Mombo · Oct 8, 2017

I am thinking about adding 2 120mm computer fans into my stand for ventilation.

It seems like I have seen quite a few people using fans like this.

How are yall making it work with the normal plugs you have available to you around a fish tank?

Flippers4pups · Oct 8, 2017

Computer case fans usually run at 12v. Wiring them to ac adapter that converts 110v to 12v is needed. Called “wall warts”. Universal ac adapters with adjustable settings is what you see most now sold and can be adjusted to 3v -12v. Best Buy sells them.

Mombo · Oct 8, 2017

Use something like this then. Cut off the end I marked in red and then wire it up in parallel I assume.

redfishbluefish · Oct 8, 2017

That would certainly work.....but a couple of pointers:

1. When you cut off that end plug, one wire will be positive, the other negative. You need to hook up the positive wire to the positive side of the fan. If you don't, the fan will run backwards.

2. Amps are additive. If you are hooking up multiple fans, you need to add up the amp rating on each fan, and this number can't exceed the amp rating of the power supply....with the one you've shown, 3 amps.

Flippers4pups · Oct 8, 2017

This is the one I use on my two 120mm case fans in my canopy.

Mombo · Oct 8, 2017

I found one on amazon made by a computer company that is made for this so that will make it quick and easy. I am going to combine these two things and then I can go with 2 fans or 4 fans if I need to down the road.

https://www.amazon.com/gp/product/B000MGG6SC/ref=ox_sc_sfl_title_5?ie=UTF8&psc=1&smid=A2F13KK758WMXQ

https://www.amazon.com/gp/product/B00MYA3A4C/ref=ox_sc_sfl_title_4?ie=UTF8&psc=1&smid=A1S9W9A986D3KF

Most the fans I looked at said 0.16A ish so I will need a lot of fans to hit the max amp mark haha.

Sleepydoc · Oct 8, 2017

A couple of more tips -

Direct the fans so they blow onto the water/into the stand rather than the other way around. The humidity and salt spray are corrosive and will wreck the ball bearings quickly if you use the fans as exhaust fans.
Think of maintenance - make the fans reasonable easy to replace for when they do wear out (they will,) and consider adding a barrel jack connector to them to make it easier to disconnect them if it should be necessary.
Pay attention to noise and airflow when you buy- some fans are much quieter than others and some blow a lot more air than others.

Edit:
If you have an Apex 2016, the DC24 outlets on the EB832 can directly power a 24v fan as long as it's less than 30 W

saltyfilmfolks · Oct 8, 2017

You might like this.

https://www.reef2reef.com/threads/diy-cooling-fan-temp-controller-easy.254168/

ChrisQ0904 · Oct 8, 2017

I’ve been looking up doing a similar project myself. Out of curiosity why not just use 2 wire fans and then you don’t need the molex adapter

Mombo · Oct 9, 2017

I like the design of the other style fans haha otherwise no reason I guess.

Good note on the maintenance part. I was planning on just screwing it into the stand but after doing that 3 or 4 times they might be a bit worn out. Need to think of an alternative for that maybe....

Don Lidtke · Oct 9, 2017

You could use these:

AC Infinity AXIAL 8038, Muffin Cooling Fan, 115V AC 80mm by 80mm by 38mm Low Speed
or
Tjernlund 8710001 High Speed Muffin Fan with Cooling Axial, 110 CFM, 120 mm x 120 mm x 38 mm, 110V AC from Amazon

Sleepydoc · Oct 9, 2017

Mombo said:
I like the design of the other style fans haha otherwise no reason I guess.

Good note on the maintenance part. I was planning on just screwing it into the stand but after doing that 3 or 4 times they might be a bit worn out. Need to think of an alternative for that maybe....

I have mine screwed into the cover for my overflow, blowing down onto the water as it comes over the weir. It's an acrylic cover, so I just drilled a circular hole for the fan and 4 holes at the corners then picked up some stainless bolts with a couple neoprene washers for vibration isolation at my local hardware store.

You can certainly use screws, too. If/when the holes wear out just drill them through and use bolts.

Pivitol · Oct 9, 2017

I used these adapters to wire up cpu fans for my equipment cabinet to keep my MH ballasts cool. They work great. I have them set on a timer to run only when the MH's are on.
https://www.amazon.com/gp/product/B00FEOB4EI/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

Ranjib · Oct 10, 2017

Pivitol said:
I used these adapters to wire up cpu fans for my equipment cabinet to keep my MH ballasts cool. They work great. I have them set on a timer to run only when the MH's are on.
https://www.amazon.com/gp/product/B00FEOB4EI/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

I used these as well, for all 12 v DC requirements (moonlight, kessil controller, dosers, fans [part of temperature controller]). I would repeat the same advice shared before, check the amp rating with your fan's consumption, and check for UL listed products only.

It is trivial to control their speed as well

, i.e you can actually ramp up or down the speed of the fans based on certain conditions.

MSB123 · Oct 10, 2017

I hope this turns out to work! I would love to try it!

bblumberg · Oct 11, 2017

I have no doubt that all of these cheap wall warts will work for a while. I, myself would not like to rely on them. Instead, pay a few bucks more and buy a UL listed 12v or adjustable power supply that is not likely to catch on fire or fail after a short time. Just search for 12v UL listed power supply on Amazon and pick the one that works best for you. As others have noted, in series, current is additive while in parallel, volts are additive.

I use pigtails like these to connect power supplies to fans and such.
https://www.amazon.com/JacobsParts-...7760288&sr=8-11&keywords=2.1mm+female+adapter

I also like to spend a few bucks more and get IP65 or higher fans.

Bruce

George Lopez · Oct 11, 2017

Honestly im running a 12V waterproof ball bearing computer fan and controller off of an old 12 Volt charger i had and just loped the terminal off of. The fan doesn't really take much power so just a small plug not a large box. And the controller as also 12 Volt so its runing both.