My Home Made Fan Speed Controller

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02-23-2004, 03:23 AM
tesco

im making a fan speed controller +on off switch out of parts from my old power supply that broke...I took the on\off switch off the back to use to control the fans, turn them on\off. And i also got the voltage selector (switched 115v to 230v) to choose between 7volts and 12volts for all my fans. the on\off switch will only control the graphics card and intake fans for when i go to sleep and the computer will be mostly idle.

now i need to know two things about the voltage switch:

1) will it be able to handle such a litle voltage :lol: sounds stupid but i need to know lol.
2) it has 3 wires on it, 1 will go to the 4 fans, one to the 7v and one to the 12v. Which one on the switch is the one for the fan? will it be the middle one? or ne of the sides?

im also working on a 5.25" drive bay cover which i am cutting parts out of to make a control switch with the two fan switches and im attaching some leds later on to tell me if the fans are running or not (i guess it will be to tell me if the voltage is being received by the fan? either way it will still look kool :lol:
02-23-2004, 03:56 AM
lynx

Quote:

Originally posted by ROSSCO_2004@23 February 2004 - 02:23
im making a fan speed controller +on off switch out of parts from my old power supply that broke...I took the on\off switch off the back to use to control the fans, turn them on\off. And i also got the voltage selector (switched 115v to 230v) to choose between 7volts and 12volts for all my fans. the on\off switch will only control the graphics card and intake fans for when i go to sleep and the computer will be mostly idle.

now i need to know two things about the voltage switch:

1) will it be able to handle such a litle voltage :lol: sounds stupid but i need to know lol.
2) it has 3 wires on it, 1 will go to the 4 fans, one to the 7v and one to the 12v. Which one on the switch is the one for the fan? will it be the middle one? or ne of the sides?

im also working on a 5.25" drive bay cover which i am cutting parts out of to make a control switch with the two fan switches and im attaching some leds later on to tell me if the fans are running or not (i guess it will be to tell me if the voltage is being received by the fan? either way it will still look kool :lol:

Can't tell you which pin is which without knowing the exact make & model of switch etc.

Number the pins 1, 2 and 3.

Connect 12v to the fan.
Connect pin 2 to the fan. Connect pin 1 to ground.
If the switch does not work in any position then pin 3 is the common one.

If the switch works in one position, disconnect pin 1 and connect pin 3 to ground. If the switch now works in the other position then pin 2 is the common one. Otherwise it is pin 1.

Now connect the common pin to the fan, and the other two pins to ground and 5V respectively. You now get 12v across the fan when the switch is connected to ground and 7v across the fan (12v - 5v) when the switch is connected to 5v.
02-23-2004, 01:55 PM
tesco

Quote:

Originally posted by lynx+22 February 2004 - 22:56--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (lynx @ 22 February 2004 - 22:56)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-ROSSCO_2004@23 February 2004 - 02:23
im making a fan speed controller +on off switch out of parts from my old power supply that broke...I took the on\off switch off the back to use to control the fans, turn them on\off. And i also got the voltage selector (switched 115v to 230v) to choose between 7volts and 12volts for all my fans. the on\off switch will only control the graphics card and intake fans for when i go to sleep and the computer will be mostly idle.

now i need to know two things about the voltage switch:

1) will it be able to handle such a litle voltage  :lol: sounds stupid but i need to know lol.
2) it has 3 wires on it, 1 will go to the 4 fans, one to the 7v and one to the 12v. Which one on the switch is the one for the fan? will it be the middle one? or ne of the sides?

im also working on a 5.25" drive bay cover which i am cutting parts out of to make a control switch with the two fan switches and im attaching some leds later on to tell me if the fans are running or not (i guess it will be to tell me if the voltage is being received by the fan? either way it will still look kool :lol:

Can't tell you which pin is which without knowing the exact make & model of switch etc.

Number the pins 1, 2 and 3.

Connect 12v to the fan.
Connect pin 2 to the fan. Connect pin 1 to ground.
If the switch does not work in any position then pin 3 is the common one.

If the switch works in one position, disconnect pin 1 and connect pin 3 to ground. If the switch now works in the other position then pin 2 is the common one. Otherwise it is pin 1.

Now connect the common pin to the fan, and the other two pins to ground and 5V respectively. You now get 12v across the fan when the switch is connected to ground and 7v across the fan (12v - 5v) when the switch is connected to 5v. [/b][/quote]
thanks i think the middle one is the 'common' one.

one more thing, on a molex connector which is the 12v? is it the red or yellow? and the blacksd are both ground right. (i know how to get 7v)
02-23-2004, 02:21 PM
lynx

Yellow is 12v.
02-23-2004, 10:05 PM
tesco

Quote:

Originally posted by lynx@23 February 2004 - 09:21
Yellow is 12v.

alright thakns lynx ill post back if i need any more help.