Spawn-Inc
04-07-2009, 10:01 PM
here is a simple way to switch from 12v to 5v mainly for your fans. i use it for benching so i don't have to pull the molex plug out and take out my adaptor. instead i just flip a switch and i'm good to go :)
wiring diagram
http://img23.imageshack.us/img23/1048/spdtp.jpg
and here is what it should look like when soldered up
http://img25.imageshack.us/img25/6133/img0207p.jpg
and here are the switches installed to control the fans on my 2 rads.
http://img5.imageshack.us/img5/6997/img0210m.jpg
think thats all i need to explain it, if not tell me what i need to add, or any questions you have.
i know people ask about it so hope it helps.
EDIT:
i added diagrams for a 5v,7v,12v setup as well as a 7v, 12v setup.
12v and 7v and 5v switch
as for the switches you would need 2 of them to get 5, 7 and 12 volt options. they would have to be double throw single pole or double pole double throw.
here is a wiring diagram to do it. note the legend
LEGEND
black wire = ground
red wire = 5v line
yellow/green wire = 12v line
http://img233.imageshack.us/img233/5161/switchu.jpg
here is a better picture.
http://img212.imageshack.us/img212/6866/new1275.jpg
- you split the 5v line to 1 side of both switches.
- on the first switch you run the middle leg to the fan's red/power wire.
- you either join both ground wires at the molex, or just use 1 of the 2 grounds.
- run a wire from the ground (black wire) of the fan to the middle leg on the second switch.
- run the ground wire to the last leg left of the second switch.
- run the 12v power line to the last leg on the first switch.
that will get you the 5, 7 and 12 volt options.
now, here is a disclaimer
when you want to run 7v you need to first set the fan to run 12v. once that is done then you can set the second switch to 5v. if you try to change to 7v operation while the first switch is in 5v then you *could* damage the fan since you would be feeding 5 volts to both sides of the fan. i personally think the fan would just stop running, but i cant say for sure or guarantee it's safety. so i am not responsible for anything that goes wrong. though i highly doubt anything will.
12v and 7v switch
looking at it again you can pull off a 12v and 7v switch with the following diagram.
http://img28.imageshack.us/img28/6798/127j.jpg
yellow is 12v
red is 5v
black is ground
red to fan is positive
black to fan is ground (negative)
if you can't figure it out just let me know, it's a bit messy but hopefully you will see where the wires go.
when and if you try this make sure the 2 sides of the switch are not connected. by that i mean it's like 2 switches in 1. i'm 80% sure that any switch that says double pole double throw is separate.
wiring diagram
http://img23.imageshack.us/img23/1048/spdtp.jpg
and here is what it should look like when soldered up
http://img25.imageshack.us/img25/6133/img0207p.jpg
and here are the switches installed to control the fans on my 2 rads.
http://img5.imageshack.us/img5/6997/img0210m.jpg
think thats all i need to explain it, if not tell me what i need to add, or any questions you have.
i know people ask about it so hope it helps.
EDIT:
i added diagrams for a 5v,7v,12v setup as well as a 7v, 12v setup.
12v and 7v and 5v switch
as for the switches you would need 2 of them to get 5, 7 and 12 volt options. they would have to be double throw single pole or double pole double throw.
here is a wiring diagram to do it. note the legend
LEGEND
black wire = ground
red wire = 5v line
yellow/green wire = 12v line
http://img233.imageshack.us/img233/5161/switchu.jpg
here is a better picture.
http://img212.imageshack.us/img212/6866/new1275.jpg
- you split the 5v line to 1 side of both switches.
- on the first switch you run the middle leg to the fan's red/power wire.
- you either join both ground wires at the molex, or just use 1 of the 2 grounds.
- run a wire from the ground (black wire) of the fan to the middle leg on the second switch.
- run the ground wire to the last leg left of the second switch.
- run the 12v power line to the last leg on the first switch.
that will get you the 5, 7 and 12 volt options.
now, here is a disclaimer
when you want to run 7v you need to first set the fan to run 12v. once that is done then you can set the second switch to 5v. if you try to change to 7v operation while the first switch is in 5v then you *could* damage the fan since you would be feeding 5 volts to both sides of the fan. i personally think the fan would just stop running, but i cant say for sure or guarantee it's safety. so i am not responsible for anything that goes wrong. though i highly doubt anything will.
12v and 7v switch
looking at it again you can pull off a 12v and 7v switch with the following diagram.
http://img28.imageshack.us/img28/6798/127j.jpg
yellow is 12v
red is 5v
black is ground
red to fan is positive
black to fan is ground (negative)
if you can't figure it out just let me know, it's a bit messy but hopefully you will see where the wires go.
when and if you try this make sure the 2 sides of the switch are not connected. by that i mean it's like 2 switches in 1. i'm 80% sure that any switch that says double pole double throw is separate.