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new fan switch

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Ekko

Member
Joined
Mar 6, 2009
hi guys....
today i was modding a fan switch, ie a switch a found that goes for a halogen stand lamp light that has a dimmer switch,
previously i had bought a switch, then i decided i wanted something that will control all 5 of my fans, ( 5 scythe ultra kaze ) with one knob..the switch i had bought over heated and burnt out..it simply wouldn't work..
this switch i found works for the light it was on..but it does not work with 12 v apparently, ive hooked it up various diffrent ways..its not enough volts or amps or something I'm assuming..this switch is much bigger and has a heat sink for it even..
i think maybe the resistor is too big or something..
the switch i found was on a light like this..
http://www.instructables.com/file/F...-to-Fluorescent-Torchiere-Lamp-Conversion.jpg
this is what the switch looks like..
005jqr.jpg

006ew.jpg

007hy.jpg

you can see the new switch even has a heat sink in case it heats up..
I'm not too smart with with this type of modding ie electrical..
can someone help out please? thank you for your time
 

Conumdrum

Member
Joined
Sep 15, 2007
Location
Small town Emlenton, PA
You can't. The variable pot won't have enough amps to handle a DC fan by itself if you were to unsolder it. There are circuits on it that are meant for JUST AC input. it works by using a variable RCL circuit to tell the Mosfet to shut off for most of the cycle at low output, it needs a AC input to work, AC is a sine wave, DC is a smooth voltage and never changes. An RCL circuit is ONLY for an AC circuit. Well kinda.

in short, no workie in your application.
 
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Ekko

Member
Joined
Mar 6, 2009
aww no workie, shiser!!!!!! lol..well thanks for explaning to me..:)
 

Ben333

Folding for Team 32!
Joined
Feb 18, 2007
Go to your local radioshack and pick up a 2.5W rheostat, makes a good DIY fan controller.
 
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Ekko

Member
Joined
Mar 6, 2009
i dont want that im a custom modder ...thats not custom :)
 

Conumdrum

Member
Joined
Sep 15, 2007
Location
Small town Emlenton, PA
Okay! You'll need one for each 3 fans or go bigger. You know what you linked to at digikey will use ALL the power? What I mean any decrease in fan speed by using a reostat will be dissipated into it? There is a link on how to make your own proper fan controller at the top of this forum. Using a straight reostat isn't a good idea.
 
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Ekko

Member
Joined
Mar 6, 2009
you im going to look for a bigger rehostat..but i may jsut connect 3 of thease to the one..
im going to run them low anyway...
 
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Ekko

Member
Joined
Mar 6, 2009
thankyou i see that..its great reading..thats what got me thinking in the first place..im not sure i can build it thoe..ill try..
 
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Ekko

Member
Joined
Mar 6, 2009
today i picked up a 3w rheostat.. i sen a guide on how they work... this should work ok for 3 fans... the guide shows this same rheostat connected directly to the 12v molenx connector line... it controled the entire 12v line... ill let ya know how it goes after i hook it up...
i also read another guide how to use a blackberry psu unit and make a fan psu with a switch.... pics later its awsome...
you guys have helped me tremendously!!!
 
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Ekko

Member
Joined
Mar 6, 2009
updated wired all fans to it..it got so hot after 5 minutes it started melting the acrylic..i could not even touch it..clearly i need a 50w rheostat with heat sink and fan LOL
ill hook up one fan later just to see if it will even work with one fan..it was a neat little lesson to wire it all together like that...
 

muddocktor

Retired
Joined
Nov 1, 2001
Location
New Iberia, LA
....clearly i need a 50w rheostat....

Ask and you will be linked to one. Pretty pricey though.

Why not buy a fan controller such as this one, then after checking it to make sure it's good you take the guts out and build your own housing for it. That way you get the benefits of PWM fan control without having to actually design and build the controller, with it being installed in your own custom enclosure.
 
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Ekko

Member
Joined
Mar 6, 2009
i was thinking that..
the reason im considering doing it this way is i want one knob for all of the fans..
thankyou for that link..:)
 
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Ekko

Member
Joined
Mar 6, 2009
one day im going ot buy one of those 200w rheostats wow man..its like gurnateed to run anything period LOL
also i wanted to thank you all for your help, a he suggested an easier route, to buy a big rheostat 3v or above..i did it works great..sorta...i seen this rheostats get really big 100 v 200v 50 v wow.so i bought a 3v rheostat that works just fine with 3 dc scythe ultra kaze on there..
it seems to get a little hot that's really it..i had connected 7 scythe ultrakaze to it and it literally melted my acrylic..pretty cool eh? LOL
also found some old parts hooked up ad dc blackberry charger to the wall wired to a 140mm delta with a toggle switch..its so quiet and its only at 7v so better be quiet..
it looks like a modders fan lol
001cxl.jpg

a real modders desk fan LOL
002rn.jpg

003mb.jpg

004re.jpg


I'm a little concerned that this switch got so hot it melted acrylic..
do they normally get this hot?
its less with 3 fans on it..still get hot..
is there a way to get rida this?
solder a heat sink n fan on it ?
 

Spawn-Inc

Member
Joined
Jun 13, 2007
not sure if you want to go with just switches, but i have some diagrams for several switch setups including a 12v to 5v, 12v to 7v, or all 3 with a 12v, 7v, 5v setup.

Here is my guide like attempt.

you can get 120v switches as it's just a switch and no resistors and such.
 

Conumdrum

Member
Joined
Sep 15, 2007
Location
Small town Emlenton, PA
Thats why a Fan controller is better than just a Reostat. I mentioned it.

Custom is great. Custom with no real knoweledge of what your doing is another. Your stuff.
Please read up on making your own proper fan controller or buy one.

Please don't burn your house down.............