My CCFL and Mobo pinouts

[sims5487]

Help! My mobo has two pins for the HDD activity light, but my CCFL has three pin holes! Where do I plug this in and how, if I want it to blink with HDD activity?

[richmandudeus]

question: does it have 3 pin holes and two wires? Or, does it have three wires?
if it has 2 wires, you can just cut the housing in half to fit it into single pin mode. If it has 3 wires, then you got me. I've never seen a hdd led with 3 wires b4. Sorry if this doesn't help.

[crenn]

If the CCFL has a switch with 2 wires then replace those 2 wires with a 3v relay. That should work. If you don't understand, just say. I've got my dog tugging on my sleeve.....

[sims5487]

question: does it have 3 pin holes and two wires? Or, does it have three wires?
if it has 2 wires, you can just cut the housing in half to fit it into single pin mode. If it has 3 wires, then you got me. I've never seen a hdd led with 3 wires b4. Sorry if this doesn't help.

It DOES have 2 wires (the middle pinout of the housing is apparently empty)... I guess my next question is how do I know which wire is + or -?

[richmandudeus]

cut from the center which would be the empty pin slot.

black or white is usually the negative. It doesnt really matter if you put it on wrong. it just wont turn on or light up if its wrong. if thats the case, just switch em around.

;) :)

[crenn]

Remember, you can actually blow up either your mobo or your CCFL as the mobo pins do produce some voltage.

[MrSlacker]

Remember, you can actually blow up either your mobo or your CCFL as the mobo pins do produce some voltage.
what he said. you can accually blow up your entire computer. this will cause your house to get on fire. just remember, be CAREFULL. if you mess up, you are ****ed . so just take it easy and do what you have to.


:p :p :p :D :D

[sXenoG]

Its true you can screw things up. I dont kno if this one would kill the entire computer but it is plausable.

I kno that the ccfl could blow tho might take a bit but will eventually. In my digital electronics class the teach told us to never do reverse it.. So i decided to i smelled the gate burning so did my friends os i decided to stop but later i burnt out an LED just for fun since there was about 500 in that class for about 8 people :)

[sims5487]

Well, the wires arent marked... anyway to test and tell other than guess and check?

[Dark-hobo]

well, if you run more than 5volts through an LED(at least the ones in my class) they you pop. It was awesome! I only did it once though, however my friend ken did it like 3 times... I also blew up a diode with AC current :D. Electronics was fun!

[Dgephri]

lets just get some basic Motherboard information straight:

Most boards use 3V for the LEDs...and less than 20mA. Your CCFl takes 12Volts, and likely half (.5A or 500mA) an amp in DRAW. As I understand the process, the CCFl will draw as much as possible from the motherboard, even though it likely has a limiting resistor somewhere on the LED circuit.

Your CCFls won't light up at only 3Volts. And you run the risk of drawing too much from your motherboard LED circuit as well. Do some reading, and get a proper relay.

I have safely used a Crydom DMO 063 to control as many as 6 CCFls. You can't, shouldn't, and hopefully won't, hook it up to your motherboard directly.

[Malatory]

Looking thought this thread and one 1 person is trying to help and that is Dgephri.

You will likely kill your mobo hooking up a CCFL to it. As stated above. They are 12V and the header your trying to use is only 3V.

CCFL are made to run off the same molex conector as Hard drives. If you just bough a CCFL and no Inverter then your trying to add a AC device to a DC power. Yet another way to kill things that you wanted to keep.

[slaveofconvention]

The best, safest, and most reliable way to make a Cold Cathode act as a HD activity light would be to buy a very fast reacting relay, then wire the cathode kit up as normal, except using the relay instead of the manual switch (if it doesn't HAVE a switch then you can just cut EITHER (not both) of the power wires BEFORE the inverter and have the relay in there. Then you wire the relay to the motherboard.

When you buy the relay, make sure you....

1. Get one which will switch with 3v or less (as mentioned above, thats all a motherboard pin-out usually provides)
2. Can handle 12v DC across the switch (because thats what the cathodes run on)
3. Will react fast enough to actually have the light come on before it's turned off again.
4. If possible, I THINK you need to get a SPST (Single pole, single throw) relay as this will be easiest to wire up. It won't confuse you with extra terminals you don't need.

It definitely isnt as simple as connecting s CCFL tube to the mobo pinouts. I don't think it WOULD fry the board, but it definitely wont work.

Ask in your local electronics shop - they should be able to help.

[Dgephri]

use a Crydom DMO-063, 0-3V control line (like your motherboard pins)

0-60V load (you are only working 12V) up to 3Amps! $15, 4 pins, and you can do it. There are 555 timers, and some circuit designs that do basically the same thing.

I have personally used this relay to power up 3 pairs of CCFls, and currently run 2 4LED UV clusters (8 UV LEDs).