Custom fan controller - assistance required

Z

zerocount

n00b
Joined
Nov 22, 2006
Messages
51
I am currently putting together (whoops, attempting to put together) a standalone cooling solution for an entertainment cabinet. It currently houses a bunch of components, including my HTPC, and I am unhappy with the warm air I feel wafting out from the shelving unit.

Here's what my original plan was (keep in mind that, for all intents and purposes, that I know little to nothing about electronics):

- Use a fan controller originally purchased for a PC (so it has a molex connector to provide power) to control the
- Four 120mm case fans, attached to ventilation areas of the shelving unit
- use an adapter/brick from a usb-sata kit to power the fan controller

And enjoy the breeze.

So, I pull all of the components together, plug the adapter into the controller, and... nothing. When looking at the adapter, it appears that connector #2 has no contact surface in it... just a plastic hole. Is this the cause of my problem? Am I missing something more elementary? If I want to complete this little project, how can I power the fan controller in a safe and effective fashion?

Help!
 
I also have an adapter for the IDE/Sata USB thingy and the missing pin is the problem. If you look closely you can see the ground wire for the fan used that ground wire (There are supposed to be two grounds there in the ATX Spec but since it's a cheap adapter they (China) only used one)
 
You could put an adapter together which basically swaps both ground wires in the molex connectors at each end of the adapter. So pin 1 and 4 stay the same (5 and 12V) while pin 2 and 3 are reversed, thus connecting the ground (one ground wire should be enough) and make things work.

Alternatively get another power adapter :)
 
If problem is ground wire being in only one/"wrong hole" in Molex connector it should be rather easy to fix that.
Just look carefully into connector and you'll see two metal strips protruding outwards from opposite sides of metal contact.
I've used needle for bending those metal strips inward so that contact can slide out from connector, then just bend those strips again outwards and push it into required hole.
 
E.T said:
If problem is ground wire being in only one/"wrong hole" in Molex connector it should be rather easy to fix that.
Just look carefully into connector and you'll see two metal strips protruding outwards from opposite sides of metal contact.
I've used needle for bending those metal strips inward so that contact can slide out from connector, then just bend those strips again outwards and push it into required hole.
Click to expand...

Depends on the connector in question (the molded Molex connector on the adapters I have seen can't be modified like that), and how much you care about warranty :)
 
Elledan said:
Depends on the connector in question (the molded Molex connector on the adapters I have seen can't be modified like that), and how much you care about warranty :)
Click to expand...

Okay (again, note that my electronics knowledge is scarce), could I "bridge" the two grounds together into a single ground? I.E. could I simply run a wire from the ground that is, well, grounded, to the empty hole onthe connector, and ground both "holes" to one ground? Obviously, I'd need to ensure that the "bridge" wire connected to the contacts in the second ground.

Is this a Really Bad Idea, or would it work?
 
zerocount said:
Okay (again, note that my electronics knowledge is scarce), could I "bridge" the two grounds together into a single ground? I.E. could I simply run a wire from the ground that is, well, grounded, to the empty hole onthe connector, and ground both "holes" to one ground? Obviously, I'd need to ensure that the "bridge" wire connected to the contacts in the second ground.

Is this a Really Bad Idea, or would it work?
Click to expand...
Yes, it's fine. Usually, the two are tied together in the end device anyway, but that appears not to be the case for you.

Another option would be to get a short molex extension cable, and solder the two grounds together in the middle of the cable.
 
Thanks for the suggestion... looks like I'll be soldering this weekend (I think I have a ton of extenders kicking about).
 
You must log in or register to reply here.
Back
Top