Cold Cathodes Sucking with longer wires?

[Fushyuguru]

Has anyone ever noticed that with extensions to the power cables on Cold Cathode lights, they take forever to get to full brightness?

Or is it just me?

[BlueWraith]

I macgyvered my cold cathode into working when it was shipped to me with a broken wire, and now it takes about a minute or so to get to full brightness. Not fully sure why, but I've not tested the second tube yet. Maybe I need to get a job and buy a bigger case... Full server tower would be nice. hehe

[ConquereR]

Originally posted by Fushyuguru
Has anyone ever noticed that with extensions to the power cables on Cold Cathode lights, they take forever to get to full brightness?

Or is it just me?

Hmm, as soon as i hit my power button my CC is at full brightness. Maybe your inverter box is bad?

[LittlePiggie]

maybe they are designed to use a specific length and gauge of wire? I know thicker wire acts like a resistor. just guessing ??

[elec.tron]

I lengthend both the conductors for power as well as the wires going to the cc's themselves with no problems.

Just out of curiosity does the splice in your wires or the wires themselves get warm after its been on for a minute or two? How did you make the splice? Have you looked for voltage drop on your 12V rail while they're being powered up?

Maybe your inverter box is bad?

That would be my next guess, hopefully it can be returned for a replacement, but maybe not since you monkeyed with the wires.
Good Luck
elec.tron

[Fushyuguru]

No drop in 12v rail. Solid as can be. Im running everything without computer components installed/powered (paperclip trick).

Wires do not get hot, and there is a 12" extension, 5ohm overall resistance.

Made the splice by cutting and splicing extra 12" of wire into the line, soldering and heatshrinking new connections. No cold solder joints and resistance was measured after the splice was added.

The only thing I can think of is that the inverters, made by sunbeam, have a limited current output based off the 620volt output and the known resistance of the CC light. By adding the splice, or any extension cable, the current dropped.

What bothers me is that sunbeam offers these power extensions. With them they dont work, at least in my case. I have a storebought extension, measures 3ohms. So Im not far off.

I emailed the company to see whats up with it.

Its not the inverter box itself, I have 6 inverters and 13 cold cathode lights. Works the same way with all inverters and CC light combinations minus the 4" models. I assume they have a lower current draw.

[elec.tron]

Hmm...seems like you've got your bases covered as far as power/splice is concerned. I find it kind of hard to believe a couple/few ohms resistance would be enough to prevent the light from working properly, but then i'm not really farmiliar with how these inverters work specificly.
Someone years ago showed me a trick that works with florescent tubes, if the ballast is old and not putting out enough current to fire the bulb as in taking a long time or doing the blinking thing, you can swipe your finger across the length of the tube creating enough static to fire the bulb. I've done this lots of times and usually it works. Not really sure if this will work in your case, but if it did it would be an indicator that your on the right track as far as high resistance/low current.

I emailed the company to see whats up with it.

Curious to see what they say.

Good Luck
elec.tron

[Fushyuguru]

Yeah, thats why I am so confused. A few ohms should hardly make the light useless.

Ill have to try the finger swipe.

No response yet from the company.

Also, Ill try and take a picture of what it looks like.

[Kino]

it could be the CC bulb itself, but since you say its new, the odds of that are lower
my ceiling fluorecent light takes up forever to get to full when its about to die