Cold Cathode Problems (This is a strange one)

[Unknown-One]

I bought a nexus fan controller that came with some nice (and very bright) blue cold cathodes; these things started out as almost blinding! After testing the cathodeas, I sleeved their wires and routed them.

There's only one problem now that the cathodes are installed...the light they give off now is so dim its pathetic! What on Earth happened?

 

[mike_6289]

if you dont use the right kind of cables, and they're too close together, your cathode will dim. i don't know the exact physics behind it, but its something to do with 1000s of volts running through the cables, and the cables being very close together.

 

[Unknown-One]

I guess I'll be takeing off the sleeving I'll report back with teh results in a moment....

/me shuts off computer

 

[Unknown-One]

Ok, that just about fixed it...they still arent as bright as when I first turned them on though. Do you think I may have caused permenant damage to the cathodes or inverter?

 

[Dillusion]

I just sleeved two cathodes i have and they stayed the same...

 

[Legion©]

Did you by any chance switch the 12v wire to the 5v on the molex when you sleeved it?
That will result in a very dim light.

 

[Unknown-One]

Did you by any chance switch the 12v wire to the 5v on the molex when you sleeved it?
That will result in a very dim light.

I just checked it, and the wireing checks out' all though, after removing the sleeving they didnt look dim enough to be on 5v anyway.

They have gotten better, just not like they were out of the box...This just gets stranger and stranger...

 

[Arcygenical]

Cathodes are really strange entities... I've had more problems with CCFL lighting than anything else... ever. One thing's for sure, I doubt they'd even run at 5v, as mine shut off at around 7v on my fan controller. Try running them on a different channel on your baybus as... maybe it's the fan controller that was damaged and not the cathodes.

 

[SarverSystems]

Make sure you don't have any of the wires looped back around themselves (aka folding).

 

[Susquehannock]

Hmmm, did you by chance cut or modify the wire between the inverter & CCFL light tube? If so that could
be the source of your problem as those are NOT supposed to be modified.

The inverters are made for a specific resistance. Modifying the high tension leads (wire from inverter to light)
negates that. In my opinion this is the source of many inverter fire stories. Improper modding puts undue
stress on the inverter thus creating excess heat.

Don't forget, those CCFL inverters are putting out over 400V, albeit at low amperage.

 

[Altron3k]

i dont really see how this could be happening, the only thing i can say is maybe one of the wires is slightly broken losing connection. Cathodes are pretty cheap, and in my experience, sometimes wiggling the wires helps. I've sleeved mine without any problems, my friend has even cut the wires and extended them without any issues.

 

[Unknown-One]

The only thing I did to them was remove the power connector on the ends of the wires so I could put the sleeving over them...and I marked the wires so they went back where they came from.

I've got an old inverter to try these two dim cathodes on, and another cathode I can try with the fanbus's inverter...I'll let you know what turnes up.

[Edit]Another strange thing I'm starting to see here....do cathodes need any warmup time? My extra cathode appears to ramp up to full brightness over 30 to 60 seconds, and it happens fast enough to notice it, while the two cathodes that are giving me problems just stay at a constant brightness[/Edit]

 

[Unknown-One]

It’s not the inverter; no matter what inverter I put the cathodes on, they stay the same brightness.

So, now that I know the problem is with the cathodes themselves, what could I have done to screw them up? The only thing I can think of is heat damage, caused when I used a heat gun on the shrink tubing that went around each end of the cable sleeving...maybe I should have stuck to zip ties