My railsounds board melted....literally (Update-3/5/12)

 UH Oh another QC thread!

You didn't breathe in any of that smoke from that melting board did you?

Rick,

I don't know if you want to say that its another QC thread but I am just trying to bring awareness to the potential buyer.

Another great intelligent answer from you Greg! You are getting good at this aren't you! You must have a lot of free time on your hands.

All I can say I'm glad you were there to kill the power. It might have gotten ugly. Kudos to you for alerting others to this. If this is the third time you might want to consider other options.

This will turn ugly they always do, in all seriousness, that board sure got hot,I've never seen anything like that before. I'd like to know what would cause that.Wheres Dale Manquen and some of the other "electronics gurus" with some thoughts on this?

Yeah god forbid if I decided to walk out of the room while it occurred!

Thanks anyways electroliner! Just trying to help the train fanatic population!

Well, Rick, when I called Lionel, Amy, the customer service lady sent me over to a technician and he said that it has something to do with the power board which is why I am sending that board too along with the railsounds board.

Thank God I don't have to send the entire thing! I trust they will get it fixed but it just goes to show that these railsounds boards are extremely sensitive. I think the power board failed and let too high of a voltage or amperage into the railsounds board and fried it.

How did the fish fare through all of this? 

Had a MTH PS2 Pacific commit suicide on me a few years ago in much the same manner.

It was running along fine (in conventional), made a loud pop-buzz-whoosh (the magic

smoke) and died. Opened the tender and it looked like someone had built a campfire

on a spot on the board. So sad.  

Oh come on Mikey, it's all in jest. 

Yeah I never realized a board could melt itself. Oh well its Lionel's problem now they will fix it for sure though.

"Wheres Dale Manquen and some of the other "electronics gurus" with some thoughts on this?"

I suggest you post this and the picture to the electronics page of the Forum. I'd love to see the responses!

Chris

LVHR

Not just toy trains...

http://www.standard.net/storie...-fire-across-country

What I find unusual about this it appears to be the audio board and not the audio power board. The audio board simply makes the sounds but rarely has high currents flowing through it. One can only speculate what caused this to happen. I'd be surprised if Mike and is staff will be able to determine what caused this but if they do and tell you please let us know.

Pete

The power from the power supply board is generated strictly for the audio board, so there's power there.  It's not at all unusual for a fabrication error or a defective PCB to cause such a fault, I've seen a number of them in high-reliability aerospace applications where you'd think the QC would be much tighter.

It happens, and I'm sure Lionel will simply replace the board(s).

Pete,

Yeah it is the audio board but the power board I think might of failed first. That's why the technician wants me to return both the power board and the sound board.

I totally agree John.

They will replace the boards no matter what but the technician wanted the power board because he think just from talking to me that it is the problem.

I think he may be right.  If the power board went nuts and pumped out excessive voltage, it could easily fry the audio board.

Exactly John. Railsounds boards are extremely sensitive to high voltage. And I run my transformer on pretty high voltage so that I get good lighting, etc. Of course nothing over 18 volts but I think the power board decided to quit its job and let the audio board fend for itself and you see what happens.

Interestingly enough I ran this locomotive two days before this occurred which goes to show how quickly things can change with the electronics in this engine. Maybe Lionel can make an audio board that can withstand high voltage.

While you have it open, I'd suggest you wire a TVS diode across the pickups to soak up transients coming in.  Whenever I open a locomotive, I'm adding them as I go.

Of course, wait until the warranty is up...

The power that goes to the audio board is regulated... by the audio power board as John describes. Track voltage doesn't factor in as long as its above a minimum.

Pete

John what is a TVS diode?

This is the TVS Diode I use: 1.5KE36CALFCT-ND

Description:  The 1.5KE Series is designed specifically to protect sensitive electronic equipment from voltage transients induced by lightning and other transient voltage events.

FWIW pennsypride, I've dialed back my command voltage to about 15v, after suggestions on previous threads sometime ago.Theres a BIG difference especially as far as the amount of arcing during a derailment. All of my trains run just as well and this can only extend the life of any bulbs. This probably would have made no difference for that board as it appears it was defective,but its just a thought.

So it seems to be a critical assumption that the board itself has no overload protection even if it has a critical threshold that is less then the output of the transformer? Huh?

Actually, I speculate what happened was probably a component failure on one of the boards.  Either a component just failed, say an electrolytic cap, and then caused high currents on the sound board, or the P/S board failed and caused high voltage to kill the sound board. 

Very few PC boards have internal overload protection, they're not supposed to see voltages like that.

The reason I recommend TVS protection is that many electronic failures are due to voltage spikes, especially during a derailment.

Interesting point you make Rick. I can tell you right now though that there was no derailment to cause this and I definitely think it was a defective PCB.

-Mike

John,

interesting point again. I think the PC board definitely failed and let an extremely high voltage to enter the sound board. The PC board does not show it but I think something might of fried in their too because it smells like burned rubber just like the sound board. That odor was given off in the smoke. 

I will definitely make a post to Lionel's findings. It should be interesting to see.

-Mike

I can tell you what they'll be now, "replaced boards".

Yes very true John!

Hey all:

Got the new PCB board back and the Railsounds board back. Technician did not specify how the "meltdown" occurred but just indicated that the board was "toasted" .

Put in the new boards and they sat nicely inside. Started her up and everything seems to be working fine.

My only question is there seems to be static noise coming from the speaker. You can hear it in the background from the rest of the sounds and it seems to be quite bothersome. Any reason to worry? I had left the cover of the tender open exposing the electronics to dust for a week and a half. Is there dust on the board pickups that could cause the static?

Please don't tell me that I have to send this thing back again!

Thanks!

-Mike

You don't have dust in the boards.  I hear some background noise on some units when there is no sound happening, but usually it's not noticeable when they're running and the sound is on.  If you're getting static when running, there may be something else going on.  Is this when the train is moving or even when it's stopped?

John,

It's more noticeable when the train is staying still. When it is running the static goes away a little but you can still hear it.

I just don't understand why this could be happening now.

This is just way to frustrating.

-Mike

If you hear it while it's running, I'd contact Lionel and ask what the issue is.  Usually, they'll pay for shipping both ways on a boomerang repair.

A new Lionel steamer I bought last year exploded when I put it on the track and powered up. The 2 large electrolytic caps on the audio power board completely exploded, what a noise and puff of smoke! It took a year off my life I think.

Polarity must have been wrong.

Yeah looks like I will have to contact them.... again.

Thanks for the help John.

I think I will ask for a refund this time I am done with having this engine repaired its given me problems ever since.

-Mike

Wow Dave! That's scary!

I think mine did the same thing minus the Kaboom! There were two "caps" that were melted on my audio board.

-Mike

It's not uncommon for electrolytic caps to get installed backwards.  They will work for minutes to hours and then BOOM!