I need a little help with my dimmer switch

[TrojanMan]

I got thisceiling fan dimmer switch for my ventilation fans on my cabinet. The thing has 6 wires coming out of it. I have a 12v power supply providing enough amps, two 120mm industrial computer fans, and this dimmer switch i want to use as a speed and noise control for the fans. I cannot figure out the dimmer switch. The circuit im am wiring is simple. Just 2 wires per aperatus, no ground. The power supply has a ground prong, but thats all. The dimmer has a positive and negative. Those are the two i want and i think i have. But there is a ground, i wire nutted it. There is also a wire labelled nuetral, i have no idea what that one does, i wire nutted it also and all of the rest of the nonessential wires. Doesn't work. Any help or websites with info or anything would be appreciated greatly so i could get my project goin'.

[TrojanMan]

Or perhaps a rheostat. Anybody know any good info on these?

[harmonicminor]

I have a dimmer unit for a fan I built for maybe 10 bucks I'll post a pic for you tommorrow but heres how its made. get a two receptacle box and a dimmer and 15 amp at least receptacle and a 3 conductor power cord. ground from the power cord goes to the receptacle ground connection and 1 of the hot wires goes in to 1 connection of the dimmer unit and the other goes to one of the sides on the receptacle. then the other coming out of the dimmer just goes to the last receptacle connection. mine works great I use it with one of those bathroom exaust fans that also has a power cord wired in. the fan was like another 10 bucks at home depot. the fan also has a 3" exaust that hooks right up to the 3" ducting. but are you running 12v fans? if so go to an auto parts store and just get an old fashioned heater switch and use that inline with your 12v hot lead to your motor because it is made to run on 12v and will have 3 speed settings. but I think my way is cleaner and the fan just plugs in like its being plugged into the wall. it sounds like you just need to get a normal light dimmer and dont mess with cieling fan ones. normal ones only have two wires

[TrojanMan]

HEy harmonicminor, could post some pics of what you are talking about? I am still confused. I'm not very electronic savvy

[harmonicminor]

ok let me get some and Ill have it posted in a few

[harmonicminor]

ok I was wrong the controll has 3 wires one is a ground. dont mind the shitty pics cause I put a new lens in my cam.

[harmonicminor]

oh and the black one that is wire nutted is connected to the black wire coming in

[Zandor]

Did you get this worked out? It's just line = power in to the switch Load = switched power to source. No neutral for the switch only ground.

I.E. You have one wire that has the power in from the source with no neutral wire needed. Like you use the white wire as power in to the switch then the black or "Load" wire goes back to the light or what ever. The neutral & ground is located in the main box where the make up is done. Just use one romax wire to feed the switch and you are fine. Ground of course goes to ground at the source and the switch.

[Beeblebrox.420]

Note that solid-state ceiling fan speed controllers will not necessarily work properly on a motor it was not designed for. Motors vary considerably in winding geometry, pole structure and load conditions. As such, speed controls need to be used on loads they are matched to in order to be effective. If you're fortunate, you'll get a sufficient range of control over the fan speed, but you may find you are limited to a small range of the control's sweep between the point at which the motor can start, and the maximum speed is attained. This, if it runs at all.

Does the motor have multiple-tapped armature windings, like many box fans? If so, you can adjust the speed by switching in and out different windings.

[harmonicminor]

my method works just fine with a bathroom exaust fan or any other 120v ac fan. I can also hook the exuast to a carbon scrubber. plus I can just unplug everything if needed.

[Beeblebrox.420]

my method works just fine with a bathroom exaust fan or any other 120v ac fan.
Yes, but he's using two 12 VDC computer fans. A solid-state AC motor control is not going to work for DC induction motors.

[harmonicminor]

no thats when you get a fan controll for a car and just use that. they are made for 12 volt dc current and will only give 3 settings. I just think it is easier, cheaper and better and safer using 120 volt ac stuff.

[TrojanMan]

I've decided to just go with a controller intended for computers, since i am trying to do this with computer fans anyway. Great feedback though, thanks

[harmonicminor]

well I will bet just a straight up normal dimmer like mine will work for your 12v fans too. it will limit current for you. just hook your red wire to one of the blacks on the dimmer and the other black to your motors and the green dont worry about. are you using a pc power supply? it would prolly be safer than a wall wart.

[harmonicminor]

radio shack also has wall warts with adjustable voltages that would work also