Powering up PC fan for planted tank using PSU

**David Moses Heng** · 24th Jan 2007, 22:21

Dear all,

Was checking out Victeo posting on vivarium and read about powering up the PC fan using the PSU without the motherboard for the planted tanks.

Thought that it might be useful to all the DIYers on baord.

This is another link that i've found.

Check it out...

http://www.extrememhz.com/techtip1.html

Here's one more:
http://www.virtual-hideout.net/guide...ds/index.shtml

**brianclaw** · 24th Jan 2007, 22:39

Uh... don't know if you know this, but an AC/DC(depending on your fan type) adaptor is all you'll need to power up a PC fan. It's a lot less bulky and a whole lot cheaper than a PSU.

**David Moses Heng** · 24th Jan 2007, 22:42

Yes Brian,

I'm aware of that. But i thought that the PSU thingy will be safer. Cost i believe is not an issue when safety the of our house, family and much loved tanks are at staked?

Just my two cent worth...

Cheers!!

**brianclaw** · 25th Jan 2007, 13:10

It's safer? I'm interested to know why. Enlighten me and any others who might be interested, please?

**grey_fox** · 25th Jan 2007, 15:11

Erm don't mean to be a wet blanket to this thread but isn't a PC Power supply unit (PSU) messier than a AC/DC adapter?

Speaking of safety, isn't an exposed PC PSU even more dangerous that a AC/DC adapter?

Water can trickle down the wires unknowingly, seep into the unit or an even worse-case scenario, a young one or even yourself touching the unit with wet hands.

So far I've yet to see/hear any AC/DC adapter ignite into flames or shock anyone. (I might be wrong)

**David Moses Heng** · 25th Jan 2007, 17:12

Brianclaw, pls excuse me if i'm wrong.

The ac/dc adapter is only good for one fan at the max. Suppose you would want to connect an array of fan for cooling down the tank, chances are you might need more than one tank. I understand that many people mentioned that for fan, the max they can lower is by 1 or 2 ddegrees. But i have instances where my array of fan lower my 2ft tank temp by4 degrees(I don't have a photo to post).

Also, the PSU as we know is not isolated. It comes in a case which can be incorpoarted into the hood or the cabinet. Water trickling down the wire?

well, i believe that can be easily solved by using siphon tubing dia about 10mm and silicone it.

Again, these are my views.

It's okay if there are differing views.

Anyway we are all here to share pointers and encourage each other along the way. right?

Cheers!!

Bro grey_fox,

Hope i have also answer your question.

**uklau** · 25th Jan 2007, 18:20

A higher current rating AC/DC adapter can support multiple fans. It's not hard to find one with higher current rating than a PSU. PSU is just too risky especially if there are kids around

**bossteck** · 25th Jan 2007, 18:50

Hi all,

I think Altum_lover is merely sharing some ideas he picked up from his research.

Like it or not, there exists a group of people who just like to try to salvage what other consider to be junk and put them to good use. How else can you explain why people go for DIY lights, co2 diffusers even filters and chillers? At the end of the day, the cost savings isn't that great, but the sense of satisfaction of getting your DIY project to work is! Part of the fun in DIY is the process itself.

I am sure he is not suggesting for anyone to go out and get a PSU to power a ac/dc fan. But rather, if you happen to have an unused/old PSU lying around... then this is one consideration.

Cheers!

**David Moses Heng** · 25th Jan 2007, 19:53

Eric,

Thanks for your understanding...

For hardcore DIYers, nothing beats the satisfaction of assemblying something and get it going.

DIY is the tool that all inventors utilises to fuifill their dreeams...

Cheers!!

**uklau** · 25th Jan 2007, 20:37

Hi Altum_lover, I hope you didn't misunderstood me. It is never in my intention to challenge whatever posted by anyone in AQ but it's more towards showing/sharing my concerns/experiences on safety measures while DIYing.

After an incident about 10 years ago, which I almost got killed while testing my DIY project, I always put safety first

.

To all DIYer, happy DIYing & keep DIYing. Most importantly enjoy the process

.

**David Moses Heng** · 25th Jan 2007, 21:15

Bro Uklau,

NO worries man.

We are all mature and professional grown up here. It's good that you voice your concern.

Sorry to heard about what happened 10 years ago.

"To err is not wrong, but not learning from our mistakes is sin."

Cheers!!

David aka altum_lover76

**cairocks** · 25th Jan 2007, 22:03

I may be wrong but seems to read somewhere that a switching PSU will regulate automatically to the exact wattage the fans require while using a AC/DC adaptor has to find one that matches the wattage the fans required. Some calculations has to be done to find out the wattage and there are different formulas to fans connected in parallel and serial. My knowledge on this has long been rusty and had used a PSU to power my three fans for about a year before the PSU blow out with a puff of smoke.

Now I am using a chiller so no need to do this again.

**David Moses Heng** · 25th Jan 2007, 22:29

Thanks Cairocks for the info.

**brianclaw** · 25th Jan 2007, 22:59

Originally Posted by bossteck

Hi all,

I think Altum_lover is merely sharing some ideas he picked up from his research.

Like it or not, there exists a group of people who just like to try to salvage what other consider to be junk and put them to good use.

No, it's cool, I wasn't disputing him, I was also just sharing what I knew on using an adaptor. I was quite curious to know why he said it(PSU) was safer than an adaptor. I thought there might have been something I was unaware of.

**grey_fox** · 26th Jan 2007, 07:18

Originally Posted by Altum_lover76

Brianclaw, pls excuse me if i'm wrong.

The ac/dc adapter is only good for one fan at the max. Suppose you would want to connect an array of fan for cooling down the tank, chances are you might need more than one tank. I understand that many people mentioned that for fan, the max they can lower is by 1 or 2 ddegrees. But i have instances where my array of fan lower my 2ft tank temp by4 degrees(I don't have a photo to post).

Also, the PSU as we know is not isolated. It comes in a case which can be incorpoarted into the hood or the cabinet. Water trickling down the wire?

well, i believe that can be easily solved by using siphon tubing dia about 10mm and silicone it.

Again, these are my views.

It's okay if there are differing views.

Anyway we are all here to share pointers and encourage each other along the way. right?

Cheers!!

Bro grey_fox,

Hope i have also answer your question.

Hey bro,

Sorry if I made my statements sound as if it was a challenge, but its not. Just wanted to get stuff clear. Of course, DIY-ing your own stuff equates to saving cost at the end of the day. Was more concerned about the saftey aspect of things and see you are pretty well prepared and have thought about this as well.

However, if it all turns out good and all, I am sure it will be a DIY project that many folks will want to try out.

**David Moses Heng** · 26th Jan 2007, 12:13

Bro Brianclaw and Bro Gery_fox,

I think on my part i must also apologise for being do defensive about my views.

I guess i was overly passionate about my findings.

Anyways, it's nice to know the two of bros better!!

Cheers to a better and deeper friendship both on an off line(would like to meet up with all you nice folks out there)

**tawauboy** · 27th Jan 2007, 00:03

ac/dc adaptors come in 2 favours; regulated and unregulated. regulated ones have stable output voltage until the load draws more current than the designed specifications. so a 12v 1A regulated adaptor will out 12v as long as the current drawn is <1A. if >1A the 12v output may start to drop lower.
unregulated ones start with an output voltage of ~15 to ~18V. as more current is drawn, the output voltage will start to drop. if it is rated as 12v 1A, the output will be ~12v when current drawn is ~1A. again if >1A, the output voltage will drop lower.
these adaptors generally have only a wire fuse that is designed to break when the adaptor is using too much current. through these adaptors are encapsulated, they usually come with adjustment knobs for output voltage settings. these knobs may allow water to seep in.
psu are designed for high loads so you can safely connect 10~15 fans. and there are a number of safety protection built in so they are safe to operate. also the whole unit is kept cool by the integral fan.
if proper safety precautions are taken, the psu is safer to operate because
a) metal casing is grounded and will trip the electrical supply if there are any accidental shorts
b) they are usually tested and passed some form of regulatory testing
c) they run cooler
d) they are away from the wall socket which allow power to be switched off

**David Moses Heng** · 27th Jan 2007, 00:56

Hmm....

Bro tawauboy,

you have just given me an idea...

Let me work on it before i post more threads about this on line.

Cheers!!

David aka altum_lover76

**tropic** · 28th Jan 2007, 12:00

I have successfully used this PSU thingy before.But in order to get it work even better, the box has to be made more safe without unncessary opening and proper grounding.Anyway,the psu was modded to provide 2 X 12V output and 1 X 5V output with grounding.A sandbar resistor are used to solder one of the parts inside.So if you have two fans u can use both the outputs.THe 5v one can be use for testing other electronics running on 5v range.Anyway, this is just those pSU that are modded to provide a constant 12V supply with on off switch.YOu can modd it if you are gd with electronics, other than that..its just better to be safe.