Fried Circuits...FrozenCPU.Com!

nFiniteTuning · 02-12-2005, 12:01 AM

I have had some Cold Cathodes in my shuttle...they haven't had any problems. But now I just started smelling smoke, didn't notice one bulb was off...so I pulled the little blue box that they are hooked up to, and half of it was melted..I opened it up and one of the two blue things was black and crispy...also something that looks like a....well its a little roll of wire...its not damaged, but it started to come off the trace. But it didn't. Whats wrong and can I fix it? I'll take photos in the day.

jjh221 · 02-12-2005, 12:17 AM

http://www.mp3car.com/vbulletin/show...27&postcount=6
Does your computer run? if so take them out and forget about it.

tj!2k4 · 02-12-2005, 12:22 AM

Might be karma for what you said about Mustangs.. http://www.mp3car.com/vbulletin/show...5&postcount=16

No idea about your problem though.. pictures would definitly be helpful though..

nFiniteTuning · 02-12-2005, 12:30 AM

The computer runs yes, and they are in there for a reason. If they aren't there, you can't see guts through the plexiglass. See where the top two wires are goin into? thats where the little blue box is that has the burnt **** in it.
Can't just take them out and forget it. Thats stupid.

...and nah its not karma, I only speak the truth

tj!2k4 · 02-12-2005, 12:32 AM

nFiniteTuning · 02-12-2005, 12:36 AM

I got a mad headach from the smell of the smoke that came from it. ****es me off, it all looked bad *** and was gonna look better once inside the plexiglass case I'm gonna make for it for the car. They lit back up with it, but something isn't working right in it...Dont wanna risk ****in anything else up. The bulbs still work, so thats good.

Vacheron · 02-12-2005, 01:59 AM

If the two "little blue things" you refer to are next to the plugs that the cathode connects to, then they are the cathode series capacitors which follow the step up transformer (the coily wire thing). They are often tantalum capacitors which are renowned for this kind of failure and usually fail with a plume of white acrid smoke and a crackling noise, then end up looking like a coffee bean! (they also tend to spatter black soot around the destruction zone too making things often look much worse than they actually are).

At this side of the circuit, the voltage is usually around 300-400 Volts AC, and so a capacitor dielectric breakdown could easily result in the mess you are seeing.

Does the invertor have 2 outputs? if so, do you have 2 cathodes connected to the inverter? and does one still work?

If yes, then all you need to do is replace that capacitor, though first I would plug the dead cathode into the "good" connector for an hour or two to make sure the cathode wasn't the cause of the fault.

P.S. As you have opened up the inverter, be sure that you avoid touching any components when the PC is running, 400V can give you a nasty buzz!

nFiniteTuning · 02-12-2005, 02:17 AM

Ok...well before I pulled the control device off , I turned them back on and both lights turned on...

And yes its a dual output. When I smelt the smoke, I didnt notice, but one bulb was turned off....then I turned it off....then turned it back on after blowing into it and giving a few seconds to rest and the two turned on. But I turned it off and pulled things apart. Is there anything I can replace these two caps so that they dont fail?

Vacheron · 02-12-2005, 02:31 AM

If it is the one of the caps that have failed (ie. they are in the position i described above), then they regulate the startup current on switch on when the cathodes are trying to ignite. If the cap has failed short circuit, you could be overdriving the cathode on the damaged side, although they would still appear be operating correctly. So my advice would be to disconnect them both until you get the problem sorted.

Your best bet would be to take the inverter to an electronics store and have them identified by the staff there, then replace them with the exact same type. This sounds to me a lot like a random failure and is probably unlikely to occur again.

However if you did want to add a little more durability then you could ask to go to the next voltage range up in the series. Cost is a malor issue for inverter manufacturers, and so they would have used the lowest voltage device they thought they could get away with.

Personally I would just buy a new one. I don't know about the states, but in the UK you can buy a 12" cathode which includes a dual output inverter for £2.35 (around $4.00). The caps could cost you half that on their own!

nFiniteTuning · 02-12-2005, 03:27 AM

I paid 15 bucks I think from Frozen CPU for the dual 4" UV Cathodes.

Thanks for your help man. I got really bumed that this happend. Cause lookin at my shuttle at night with them lit up...is an amazing sight to see...and whats even more amazing is...I still have like a few more wires to sleve. But I dont know if I'm gonna do that, since I'm pullin the shuttle out of the case to install in a plexiglass custom case for inside the car. Everything will stil be illuminated by a UV Cathode bulb...But most likely a single 12" to cover the entire thing this time. Who knows, when done, pics will be posted of everything.

BTW, love the FTO...thats a bad *** car, allways loved them.

Vacheron · 02-12-2005, 04:17 AM

I totally agree that getting the wiring neat is probably the most difficult part of making a good looking plexi case. Especially because if you just stuff the wires behind the 3.5" drives bays as I would on a normal case, you just go round to the back of the case and there they all are!

Here is a link to a plexi case I made a while back with 2 x 12" U-V cathodes (though they come out as blue in the pic, and bright pink on a camcorder)!
GOC Plexi Case

If you look at the closeups you can see that one of the many things I had to do was to shorten the whole ATX wiring loom to the motherboard. All the wiring alone probably took at least twice the length of time it took to build the rest of the computer!

Glad you like the FTO. I've had it for over 7 years. Mine was one of the first 10 to come into the UK and I may hold the record for the longest UK owner as everyone I knew who had one before me has sold theirs now.
I've been thinking of changing it for the last 3 years, but it has been utterly reliable and I can't find anything else I like as much. The 350Z is the only thing to come close so far.

nFiniteTuning · 02-12-2005, 10:17 PM

Nah, if I could, I'd import an FTO over here...ITs the supra of the Mitsubishi world.

nFiniteTuning · 02-12-2005, 10:19 PM

:O...DUDE, Do you have aim or msn...I need to talk to you...your like the god of plexiglass! HOLY CRAP THAT Case IS HOT!

eCar™ · 02-12-2005, 10:36 PM

Take the side off, and use a flashlight when you need to see the "guts".

nFiniteTuning · 02-12-2005, 11:17 PM

Thats just sad!