Help!, Need to MOD 3pin Power to a 4pin connector

WildSplash

Junior Member
May 20, 2010
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I am using a 12v POE (power over ethernet) to power a wireless router.
I am wanting to solder on router PCB where the DC jacks connect. There is clean bead of solder on the pin connection on the bottom of the PCB and no other attachment is hooked to this power source to worry about any conflcit developing.

Once I do this, I then want to power an LCD Display/Controller which controls an internal fan. I could just run a fan directly from the DC jack pins using a 3 pin connector.
(But I want more) The kicker is.... I want to add a LCD display with a variable fan speed dial controller with sensors so I can display Heat sink heat and also measure RPM speed on fan.
I found of these devices on ebay.
They have pre built connectors going out from the unit to run a fan from the Control/Display unit and the sensors are obviously already connected.

However the power source coming in is a standard 4 pin 12v power cable just like that built in PC case. These display/control units are originally designed to go into your empty bay of a tower on a desktop system and use the standard 4pin power connection. Remember, I want to use this device and then have it drive the fan, the question is how do I power the display/controller from a 12v 2 pin DC jack connection off this router PCB. I know the router can drive an internal 3 pin fan,so the real question is how do I connect a standard 4 pin power source to it to drive the LCD display and variable fan controller?

Again, My issue is how to use the power off the internal 12v PCB to power this display controller. I searched for a pre-built 3 pin connector for power input like the fans use to power a display, but none exist.

Another question I have is what will I need to do to make sure I do not overload the 12v power source by running all these mod devices inside the router, ( ie. The router itself, the Display and the fan powered through the display wiring options.)

I am going to put a heat sink with a fan on the CPU chip for the router inside the router. And I will add heat sink to the ram chip inside to help keep heat down as well.

I am going to overclock the chip to max and by using DD-wrt third party firmware.

Any advice will be helpful.

I will be using a WRT54G Linksys wireless router.
 
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Athadeus

Senior member
Feb 29, 2004
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I know you were trying to be very clear and specific, but your request is still difficult to understand. Perhaps this is what you are looking for?

http://www.avadirect.com/product_det...asp?PRID=14056

edit: Well, I doubt that you'd want a male molex end for driving the display. I would think you'd just want one of these:
http://www.amazon.com/3pin-power-4pin-molex-adapter/dp/B000H25PBK
but I doubt it would be that simple considering how difficult it seemed to explain and how much time you spent looking already. I'm not going to open up my WRT54G just to check though :)

If you could provide a part/model number of the display/controller thing, that would be really helpful.
 
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WildSplash

Junior Member
May 20, 2010
6
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I found similar connector adapters like this....
image.asp



---- but this is not the direction I am trying to articulate. I realize I threw a lot on the table when I proposed my question.

Here is a link to another forum where someone has done a mod to the router andadded a fan. Infact, in this tutorial the power source is POE and the bottom of the PCB is where he tapped into the Ethernet pins on the mobo. He even cut the 4 pin connector off and just used the two leads red/black to drive the fan at constant speed.

I want to take the power form the D/C jack on the mobo and power the 4 pin connector. This requirement is because the 4 pin connection is the only power connection source for a LCD display device with variable fan control.
See below...

LCD Display:
PYU0128-6.jpg


Inside view of LCD display andfan controller:
PYU0128-2.jpg


Wiring for display:
PYU0128-3.jpg


The 4 pin is the power source.
the 3 pin is the fan power source. These are already pairt of the display wiring scheme.

My question is. How to wire a from the 12v source from male solder pin on the Router circut board and go to the 4pin input power connector for the LCD display. I know one port on the 4 pin must be +12v, another ground, but I have no idea what the other two pin-ports are for going into the female 4 pin connector.

The LCD display device has the 3 pin fan connector to support the fan so the part is a mute point.

The big question then remains, since I have 12v coming in POE through the cat5 Ethernet cable and connector to the routers mobo of the router, and then I tap elsewhere onf the routers moboat the DC jack pins to power this LCD display will I strain too much on the power source overall to drive the 1)router, 2)display and 3)fan (built into the LCD controller) and do this all at the same time. They are all 12v power sources.

Here is the POE to the Router through it's etherenet connection.
too may pics to post so I created link to forum on this with pics.
http://www.techidiots.net/project-pages/wrt54gs-poe-12v-mod

This is how the router gets it's 12v is by the ethernet. At the other end of the ethernet is another router with CAT5 which is wired the same on the pin connection to send the power of the unused pairs in the cable to this router.
The D/C jack is where I would tap into to get power for the LCD display
(if it is plugged in. )
However, as I write this I just realized if I am going to get power from (POE) then the DC jack is a mute point for a power source since the power would come POE ( power over ethernet).

I may have to rethink this power source issue, if someone advises me using the ethernet as my power source to run the router and power the LCD display / Fan will be too much drain. Or maybe I can do something to mod it to work, please advise...

Anyway, Below is a you tube video showing someone using the internal DC jack of the router to power an internal fan connection.
http://www.youtube.com/watch?v=8ZfPYlkvT94&feature=related
 
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WildSplash

Junior Member
May 20, 2010
6
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0
1)
Question is a 3 pin to 4 pin bi-directional for power?
All of these connector adapters I see say 3-4 or 4-3... but the reality is they are all going from a 4 pin PC power source to a 3 pin fan. I am looking for a way to power a 4 pin connector off of the pcb of the router. Which has 2pins +/-.

2)
Where can I get a schematic on the 4 pin terminal and explanation on the wiring for what means what on the pin connection?
Obviosuly 2pins are +/-....
 
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WildSplash

Junior Member
May 20, 2010
6
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0
FYI Most of the WRT54G are wired the same from version 1.0 through v4.0
At least as far as the ethernet port and D/C jack are concerned.
I have version 1.0 but I am buying another version to do my mod, mostlikely 2. 3. or 4. the WRT54GS has more Ram on board but same layout.
 

WildSplash

Junior Member
May 20, 2010
6
0
0
Here is better LCD display with Fan and heat sensor that is what I am trying to install as a mod in the Linksys WRT54G router.
http://cgi.ebay.com/PC-4-Fan-Speed-...tem&pt=LH_DefaultDomain_0&hash=item414fadd9f1

All specs are on this ebay ad, pic's too. This should better explain the 4 pin power sourc eit has. My question remains, how do I power it from the router?
combospy.JPG


combospy-back.JPG




This new device can even act as a HDD enclosure when it is in your drive bay.
NOTE... I am not trying add the HDD part in my router...
 

Athadeus

Senior member
Feb 29, 2004
587
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76
According to http://en.wikipedia.org/wiki/Molex_connector, the yellow connection is the 12v one. Looking at my AC-DC adapter for my WRT54G, the inside pin is +, so if you can just trace that using sight or a continuity tester, I'm sure you can find which solder points to solder your + and - wires to.

You aren't going to have any power limitation problems if you're using two 12v sources. It would make more sense to just use the regular DC connection for powering the router circuitry, and the POE power for the LCD and fan, because you only have to make 1 set of modifications instead of 2.

Why didn't your friend just run an antenna up to the roof or somewhere he gets the signal? And where's the router going to be installed that is so hot it needs a fan?