CaseFan Speed Control ????

[thorin]

Does anyone have a link (or two or three) to case fan mods for POTs or 3 position switches. I recently got a Vantec Tornado for my system and would like to connect a 3 position switch to it (hi-lo-off). A link to a thermal sensor mod might be interesting but isn't really what I'm looking for.

Fan Spec:
12V
9.1W
0.76Amps
5700rpm
~84CFM
~55db

So normal operation (outlined by spec) would be the hi position of the switch, the low position would cut it in half (so it'd be ~40CFM like a regular case fan), and obviously off would be off.

Thorin

 

[thorin]

Someone?

Thorin

 

[mooseAndSquirrel]

Zalman Fan Mate

 

[thorin]

Hey Thanks for the Zalman link unfortunately the product is only rated at 6W or lower.

Thorin

 

[Moohooya]

You want more than 6W for a fan? What size fan do you have? My Panaflows draw under 2W each.

 

[DanFungus]

Originally posted by: Moohooya
You want more than 6W for a fan? What size fan do you have? My Panaflows draw under 2W each.

uhh....

Fan Spec:
12V
9.1W
0.76Amps
5700rpm
~84CFM
~55db

and--damn...9.1W?!?!??! my case fans take < 3W each

 

[Insidious]

Fan Spec:
12V
9.1W
0.76Amps
5700rpm
~84CFM
~55db

Holy CRAP Batman :Q

Is that a fan or a blower?

Anyway, lets say it's 12W (1 Amp) just to keep the math simple (you want to overrate your components anyway)

so, to cut the fan power in half, you will need about 12 Ohms rated at 12W. Go to radio crap and buy a 12 Ohm, 15 Watt resistor and get a SP3T switch rated at least 2A. connect the 12V source wire to the common terminal of the switch. Splice the supply (+) wire of the fan into a Y with one lead to the fan, one lead to the Normal terminal of the switch and the final lead gets the resistor connected in series with it, then to the 1/2 speed terminal of the switch. Nothing gets connected to the Off terminal of the switch

Hope this helps ya,

-Sid

 

[thorin]

Insidious
I suppose I coulda/shoulda thought of that (I'm sure there are similar things in my first year Comp Eng Electronics text from 5 or 6 yrs ago), thanks dude!

Thorin