Potentiometer, Rheostats and Fans

[erjin999]

I have a fan, 90mm Panaflo. It runs at 12v and uses 0.18amps. This is the fan specs.

Now, I am hoping for help with changing the speed of this fan, I need it to be quieter as I am aiming for as close as I can to a silent PC. I am not looking for general advice on making a silent PC, God knows I got enough of that browing the overclocking forums.

My question:

What type of Potentiometer/Rheostat do I need ?

I would ideally like to get it to run off 9v from its current 12v. I like the idea of variably changing that as I need to. When I do the maths, I find I need about <0.5 watts, 36~ ohms type of potentiometer/rheostat.

Anyone been through this sort of thing ? Anyone have any experience of this ?

Any and all help apprecaited.

[veK]

if you only want to adjust the speed of that one fan, a single poti is probably the easiest and cheapest way to do this:

http://www.ichbinleise.de/product_info.php?products_id=341&osCsid=2756103546ddb2b6880ea1fa9b811363 (description is in german though). just make a hole in your front panel, place the poti there and connect it with the fan... you can now adjust the fan from 5V up to 12V without steps...

if you want a bit more, like controlling more fans or have an overview of the temperatures you should go for a fancontroller... maybe something like this: http://www.aerocool.us/peripheral/gatewatch/gatewatch.htm (I own one myself though I'll sell it with my old case as soon as I have built the watercooling system).

of course there are more fancontrollers, this is just an example... but if you only want to control that one fan you should just install a poti... you should find those at a shop near you...

[erjin999]

Thanks for the reply veK. I am looking to only controll the single fan. No temp readouts necessary, just something like you showed in your first link, a pot. The only thing I can think of that one you showed is at 5V the fan wouldnt start (probably). But thats nitpicking. I will try to find one locally.

I will go for one that is 100ohms ?

[veK]

let it start at 12v and turn it down slowly then to whatever v you want :)

[Cybopache]

hj nun !

Check these sites :

www.fanbus.com

cliff will guide you through some elemental electronic basic.Like ohm`s law......hehehe

http://www.bit-tech.net/article/56/

or if you really like to use tin and tip:

http://www.bit-tech.net/article/32/

or of course if you are a really electro freak :

http://bit-tech.net/article/52/5

cheers

cybocommander

[erjin999]

Thanks cybo, I am currently searching maplin.co.uk for an appropriate pot/rheo...

Damned that all the part numbers those areticles give are all out of date  :(

[Cybopache]

well ain`t italways like that?  ::)

heres the deal: you tell me how you want it build,I get the parts here build it for you,or ship the parts to you....... ::) the parts are pretty cheap.....

Cybo

[erjin999]

Well, I am not shure I want anything built, justa rheo/pot that can do what I want (give a voltage range from 12v <==> 7-ish). I think I may have found the bugger too.

Do you think that pot in the link above would be ok ?

[veK]

I don't get the problem...

you can get potis here everywhere. I'm just sending one back together with some other stuff I ordered but don't need as they don't fit or aren't necessary...

[erjin999]

I may be confused, but I think I need one about 40R (same as ohms, right ?) and about 5w...well they shure as heck dont seem to have those at maplins, which is one of the biggest supplier of electric goodies in UK (me thinks).

www.maplin.co.uk

I could be wrong.

But if this is ok, I will just get it... Long link

[Cybopache]

OK here is a guide I have translated.

By the way ,have you thought of just using a switch?

ex.g a 2 way one....12v-7v ?

your rheo:

use ohms law. U=I.R

[erjin999]

Thanks for the reply cyboman !

I noticed he went through all that calculation (which I followed and performed for my own fan) then said "but you can't get them so just get this one". Once I stopped laughing, I found the one in the shop linked here (same as the one I posted before).

It seems closer in terms of Ohms, thats why I asked if it was ok, it seems better, just looking for second opinion I guess. I might go ahead and buy and see how it turns out.

Thanks for your effort so far.

[Cybopache]

no problem mate! ;D

I can`t open your link,but it sounds good enough.Check out this link:

http://www.fanbus.com/

click check the fan bus lab,rheostat tutorial and woala.

Look this up:

http://www.el-supply.dk/maskine.html

go to effekt potentiometers and see there?

this is an Danish site,its Danish kroners,app 7,57 Dkr. to 1 euro

Cybo

[erjin999]

Thats the bugger ! The one in the Danish site. The one that is 19 kroners. I have the same one (albeit more expensive) in the other site I linked to, the one you cannot open. The one I saw on your site is 47 ohms, the one I saw was 50 (!). So basically same thing.

I will get it from the uk supplier, about 25-30 kroners approx. But is easier to read English for me !  :P

Thanks Cyboman ! Thats the help I was looking for. I will post back here when I get it working (or take out the National Grid)

[Cybopache]

Cool,cool :D

I could`nt either find it at Maplins so...

give aword or two, when you have blown your machine to pieces,lol hehehe ::) :-X :'(

Cybo

[erjin999]

The pot I am using now (wrong one, turn it a fraction and it stops) must've been moved or on the border of cutting out the fan, becuase thats exactly what it did to my brand new Barton 3.2Ghz ! Luckly it has autoshutdown-loseallwork setting. IT was hot after that !

So I figured better do it properly  ::)

[Cybopache]

Well I found this picture of my fan controlled front.

on top I got this baybus you can`t overload, 36w

[erjin999]

I did it, i got the one in the link i gave above, the one from Conrad Someone. its perfect.

it cost