Exploding MTH PS2 GG1

Ace posted:

Reverse polarity on a polarized capacitor can make a heck of a bang. Try it outdoors with some junk parts and suitable body protection for an education.

exploding capacitor on YouTube

If you read the description, this was excessive voltage on the cap.  If you put 110V on a 25V electrolytic, it will explode in a fairly spectacular fashion.  In the DCS boards, it's a different situation.  The firecracker caps are the tantalum caps, reverse the polarity on those and they pop like little firecrackers.  Many times the the aluminum electrolytic caps will just bulge, ooze a little and release some smoke.

GGG posted:

Those Capacitors do have life.  As they age they can leak, dryout, or burst.  There are other electronics that can fail and cause those capacitors to see an overload and cause them to burst.  So in most case that older PS-2 5V board has failed.  The engine can be repaired with an upgrade board.  These types of repairs are common for the older engines.   G

Yes, I can envision that some other element of the electronics failed and overloaded the capacitor. But a 14 year life for an expensive item doesn't seem satisfactory to me. Is everyone supposed to replace their "old" PS2 boards? How about my PS1 items? Is there a recommended mandatory retirement age?

My theory, which is disputed by others, is that certain caps on the 5V boards came from the time of the capacitor plague.  I had about 30 PS/2 5V boards, and about half of them exhibited this issue.  I've actually replaced the caps on several that had them bulged but were still running.  I should have taken a picture before I tossed them, but I finally decided that I was never going to revive them and pitched them.  Here's a picture of the classic capacitor plague failure, note the bulged tops.  Some caps also had the bottom seal start to bulge and they'd be sitting crooked on the board.

gunrunnerjohn posted:

My theory, which is disputed by others, is that certain caps on the 5V boards came from the time of the capacitor plague.  I had about 30 PS/2 5V boards, and about half of them exhibited this issue.  I've actually replaced the caps on several that had them bulged but were still running.  I should have taken a picture before I tossed them, but I finally decided that I was never going to revive them and pitched them.  Here's a picture of the classic capacitor plague failure, note the bulged tops.  Some caps also had the bottom seal start to bulge and they'd be sitting crooked on the board.

Seen this many times but it is good to get all acquainted with this. I m sure you no but for others the cross on top is to re leave any pressure built up in the cap.

Years ago we use to put a cap in a UN-powered power strip and wait for the tech to come in and power things up, "BANG" made for a exciting morning

Yep the scoring in the top is the pressure relief, but sometimes the pressure pops the bottom out anyway.

I had a test equipment rack that got the TTL data lines crossed with 110V, the explosions and fire were something to behold!

You guys should hear a starter cap on a motor rated in horse power let loose .

GR John would be reaching for his holster.

    I agree with the caps being a key product life limiter. They fail often, and often "pop" too; You've just never noticed it before .

If you want to sue for cash you have it all wrong...

Sue from Cash is much more fun

Litigation, really!?

I wish each of you good luck with old computers and televisions.   We all have choices.  Some people run old trains and electronics and others choose not to do that.  Whatever makes you happy.  I just finished the first run of my Lionel Union Pacific FEF 844 .  Great sounds, great smoke, great running, and whistle smoke.  That is what makes me happy.  Enjoy what you like and be happy.

Ace, replacement (new) boards are available for PS-1.   MTH has them as new stock.  The PS-2 that has an issue is the first run 5 volt boards.  The parts are no longer available to build that board.   We now have a PS-32 board and that will make your early locomotive PS-3.  I am a fan of that board.   I still have some PS-2 with 5 volts roaming around my layout.  One at a time I convert them to 3 volt boards.  Easy job.

I wish each of you good luck with old computers and televisions.  

Thanks!

An electrolytic capacitor will often times give you warnings in the form of intermittent operation, such as a reset (or reboot in a computer).   Fixed many computer motherboards by just replacing all of the e-caps.  Your better motherboards use tantalum or ESR caps which are noticeably more expensive and have better parasitics.  Don't think you would see them in toy train equipment since it would bump the BMC up by $2-$5 per board.   Electrolytics can also fail from a lack of use, sounds strange but true.

Guys, almost every cap used a board should be available at your neighborhood electronics store.   I save every bad board in case any forum member may need a part.  All members one and all can have any part they need.  no charge.  Some can not be found.  Almost weekly, someone needs a board part.  Feel free to contact me.

MTH, Lionel, Weaver, DCRU, LionChief Plus, PS-1, and many more.

Litigation for a blown cap. Classic. I needed a good laugh, so thank you. Maybe you should buy an O-scale ambulance for your layout...so that you can chase it.

Eric Siegel

I haven't had any failures due to explosion to the best of my knowledge (except for a lab experiment in college where one of us accidentally applied reverse polarity to one.... that popped, but no one was hurt).

I've had 2 other electronic items fail due to bulging or otherwise defective caps.  I had one of those HDTV to Analog TV converter boxes for years.  One day I noticed it stopped working and read up and found that one or 2 caps was a pretty consistent risk of bulging.  Noted those caps did have some bulge, replaced them and the unit was then OK.

Also had a small LG HDTV that my sister and I bought for our parents one year.  It died probably 4 or 5 years in.  I read up and found that the Electrolytic caps in the power supplies tended to crap out and cause the problem.  Didn't try to troubleshoot to figure out which cap(s), but ordered every electrolytic cap on the board (~20 caps , I think) and replaced them and the TV works fine again for probably another few years at least now (I'm thinking it was at least 3-4 years ago now that I did the replacement).

I think I somehow escaped the computer one referenced in a few previous posts.

-Dave

Marty Fitzhenry posted:

II just finished the first run of my Lionel Union Pacific FEF 844 .  Great sounds, great smoke, great running, and whistle smoke.  That is what makes me happy.  Enjoy what you like and be happy.

Marty, I could be happy to get one of those!

Youzzzz guys are hilarious!!!!!

Thank you for sound advice and LOL.  I think it's time to truly regress to childhood and back to POSTWAR!!!!

It is the 5 volt board with the suspect expliding cap.  So can the cap be replaced or does the whole board need replaced.  The passengers are fine, the ambulance is on the layout and the case has been settled out of court!!

Airbus Captain here.  Nothing ever exploded on anything I flew.  Sure had a lot of explosions in the simulator, but the worst thing we ever had happen on a real 'Bus was the passenger light and stewardess call buttons would get confused.

If you want Mil Spec capacitors in your MTH, be prepared for a doubling of the cost.  For airplane use, a $3 capacitor costs over $100 from the discount source.  And they still occasionally go bad.

Marty Fitzhenry posted:

Guys, almost every cap used a board should be available at your neighborhood electronics store.   I save every bad board in case any forum member may need a part.  All members one and all can have any part they need.  no charge.  Some can not be found.  Almost weekly, someone needs a board part.  Feel free to contact me.

MTH, Lionel, Weaver, DCRU, LionChief Plus, PS-1, and many more.

 

Hello Marty........

I wonder what happens if you light a short fuse to this box ?

Tiffany

That is not in my plans.

Steve Klett posted:

It is the 5 volt board with the suspect expliding cap.  So can the cap be replaced or does the whole board need replaced.  The passengers are fine, the ambulance is on the layout and the case has been settled out of court!!

 

  I'd replace the cap, and cross my fingers that something else didn't cause it to pop. They aren't very costly at all. One can't know for sure until they try either.

   I don't know the board, but I guess I'd check the bridge rectifier too (or the diodes that do the same job [or are connected to the cap]), you just might have a bad one that caused the pop.

    On big boards for TVs etc., with many old caps, and an unknown issue, a repair shop may swap out all the relevant caps, vs searching for a bad part first. It's often the fix, and can be cheaper than the time spent probing for a bad part.(and condition checking on caps isn't real easy. Suspect? Just swap it.)

Years ago I had some axial leaded tantalum caps.  The failure mode for reverse voltage was the tantalum slug would heat up red hot and shoot out of the the steel jacket like a missle.  Much more exciting than the electrolytic confetti firecrackers, unless the hot slug lands on your arm.  

gunrunnerjohn posted:

My theory, which is disputed by others, is that certain caps on the 5V boards came from the time of the capacitor plague.  I had about 30 PS/2 5V boards, and about half of them exhibited this issue.  I've actually replaced the caps on several that had them bulged but were still running ...

This is news to me, thanks for the information. So I gather that we can do visual inspection for bulging capacitors on electronics from that time frame (1999 to 2007) and maybe be aware of an increased failure risk.

End of the plague    [from the link above]

With the first publicized press releases, about the widespread problem with premature failures of Taiwanese electrolytic capacitors, appearing in September 2002, it might be assumed that, by mid-2003, the affected capacitor manufacturers would have changed their production process and used a "correct" electrolyte mixture. With a typically shortened life span of about 1.5 to 3 years for the failing capacitors, from mid-2003 up to mid-2006, the last of the bad capacitors should have failed by 2007. Commentators on the Internet often predicted the year 2007 would be the end point for "bad capacitors".

But maybe some suspect capacitors would fail at later dates if they were only seeing intermittent use?

"The last of these capacitors should have failed by 2007".  We still have these bulging capacitors 9 years later in 2016;  failing on engines that are being used on a routine basis.  Therefor there clearly is another mechanism causing failure too.    Additionally, PS-2 3V use the same capacitor and went into production as early as 2003/4 and I have never seen one with a bulging capacitor (and I have seen a lot of PS-2 3V boards).  G

I never said there wasn't another failure mechanism in play for these boards.  The capacitor brand that I've seen with the issue is Wincap, and I've never seen that brand on a 3V board.  I just checked at least a dozen 3V boards, good and bad, no Wincap brand on any of them.

Every incidence of a bulging cap that I had on the 5V boards was the Wincap brand, that can't be a total coincidence.  They may have just been a lousy quality cap, and that would have the same result.  I do know that if I see one of those on a working board, I replace it.  Since it's one of the few components you can reach and replace, I figure it's cheap insurance.

Capacitors lead boring lives. Eventually some of them can't take it any more and end it all with a spectacular failure. The OP should feel lucky that he got to witness such a rare event and give the offending part a proper burial.

My UP fef just blew the cap that gunrunner pointed out as the most common one.  I have a box of extra parts that looks like martys on a smaller scale and I was able to find a 35v 330uf cap on an old lionel board.  Switched that with the blown one and only thing I have is a very faint buzz from the smoke unit area.  Any one have any other ideas what I can test on the board or does this one get relegated to the parts box?  Kind of disappointing I was going to use it to pull around the Christmas tree.  

If the cab exploded, you may be too late for the repair.   I have a couple of 5V boards in my parts box that I'm saving for replacing any of mine that bite the dust, they all have new capacitors in that spot.  The one was already bulging when I got the board, I replaced the cap and it's doing just fine.

Well rats, thats kind of what I was expecting to hear.  Also have a UP challenger that blew up in a spectacular fashion last winter its been sitting on a siding since.  If my recollection is correct it was violent enough to hurt neighboring parts on the board, saw that and just put it back together and parked it.  At this rate it may make sense to model A UP scrap yard on my layout!  How to make a scale torch man?

Sadly, when the 5V board dies, it's usually dead for good.  I have a big box of dead ones, and I tossed about twenty of them not long ago.

Rather than a UP scrap yard, how about an MTH scrap yard!!!!

PS Rumor has it that Mike Reagan is history with Lionel - hopefully Mike Wolf is listening!!!

If you have a conventional transformer there always the option of a bridge rectifier to get the train moving for the holidays. Bing and Ives sound better  during the holidays anyhow.....( Crosby and Burl were my thoughts )

Pat Kn posted:

Get real!  He blew a capacitor. It happens in electronics all the time. Litigation? Come on . . . 

Agree.  Then many people whine, "why aren't things made in the USA anymore?"  Maybe because Americans are the only people stupid enough to think litigation is worthwhile as a means of solving anything but the most severe problem.  Look in the mirror folks next time you ask the "why things aren't made" here question.

In aerospace  there is usually at least one engineer assigned with a task of deterring mathematically the reliability of every part and piece that goes into a space or military product. Every electronic part has a Mean Time Before Failure (MTBF) based on statistics. They can control what parts the engineer can not use in specific designs. The reliability engineer comes up with a MTBF for every electronic system, sub-system, every PC board and each component. Everything has a MTBF. For components the electrolytic capacitor has one of the lowest MTBF and we as engineer avoided using them. They are an inexpensive way to get a lot of capacitance in a small package. If anything on a PC board is going to fail it will be an electrolytic capacitor. The older the electrolytic the greater the chance the part will fail. Over voltage plays a part too. 

It is too much to think that an model train engine 10 years old and used regularly will not suffer an electrolytic capacitor failure if not now then later, but eventually. When electrolytic capacitors are used there is a gamble as to when they may fail. If it fails outside of the warrantee the manufacturer wins. If you have the device for many decades before it fails you have won. 

If you want excellent reliability that requires regular maintenance to obtain then stick to conventional old non digitally controlled trains. Changing brushes is about all you will ever have to do. Some century old classic engines are still running today.

Litigation is a nasty word in today’s world because we have too many lawyers chasing too few real legal problems.

LDBennett

Steve Klett posted:

Rather than a UP scrap yard, how about an MTH scrap yard!!!!

PS Rumor has it that Mike Reagan is history with Lionel - hopefully Mike Wolf is listening!!!

It is not a rumor that Mike Reagan left Lionel. It was announced on this forum some time ago much to the detriment of it's members. There is a 6 page thread about it:

https://ogrforum.ogaugerr.com/t...-resigns-from-lionel

LDBennett posted:

In aerospace  there is usually at least one engineer assigned with a task of deterring mathematically the reliability of every part and piece that goes into a space or military product. Every electronic part has a Mean Time Before Failure (MTBF) based on statistics.

It was frequently amusing to see what MTBF figures we came up with doing the mathematical analysis of each component.  Sadly, how the circuit is designed usually has a far greater impact on MTBF of the product than the computed value derived from the component calculations.

It is too much to think that an model train engine 10 years old and used regularly will not suffer an electrolytic capacitor failure if not now then later, but eventually. When electrolytic capacitors are used there is a gamble as to when they may fail. If it fails outside of the warrantee the manufacturer wins. If you have the device for many decades before it fails you have won.

 Actually, electrolytic capacitors can and will fail if they're not used at all.  Electrolytic capacitors are different from other capacitors. They rely on an oxide layer that forms on the aluminum plates as an insulator to handle the voltages - the oxide forms from current passing through the electrolyte. When an electrolytic capacitor sits for extended periods of time, that oxide layer slowly disappears, dramatically reducing the voltage capacity.  Your electronics actually works better if the electrolytic capacitors are energized periodically than if they are idled for years.

Marty Fitzhenry posted:

Good points guys.  That engine was made about 15 years ago.   Would anyone expect a computer or TV to be operating that long.   Not time to go after anyone.  Old electronics.  My guess is it had an old battery in it.  Litigation--I think not.

My Tv is on 8-10 HOURS a day. And yes I do get 10-15 years out of it. His Locomotive may be 15 years old but really how many HOURS has it been run..maybe 5. Litigation isn't the answer or even worth it. I understand his frustration. Do you expect a part to fail when it is not in use 95% of the time?

John:

In my youth my hobby was photography. I took sports pictures for spending money during college. Since it was action based, a higher power electronic flash unit was necessary. The ones available in the 1960's used big electrolytic capacitors to store charge from a 300V (??) battery. If the unit sat unused for a week or more the electrolytic would not operate as a capacitor at all. One of my units had to be plugged into the wall for several hours so that the electrolytic capacitors could be "formed" in order to get to normal operation.

Since in that stage of being un-formed, they were basically a resistor. That would generate heat. Heat is bad for any component and I would think too many cycles of use/long wait/use again might shorten the life of an electrolytic capacitor (??).

In the case of the original poster, he is asking too much of almost any electronic product that includes electrolytic capacitors, I would think. Every thing has a lifetime.

LDBennett

Adriatic posted:

You guys should hear a starter cap on a motor rated in horse power let loose . 

Just what I was thinking, having been on the other side of a very thin wall when a cap in a 200 hp variable frequency drive blew. Um....quite loud.....  no dust left on the rafters there.

Since electronics troubleshooting holds no hobby enjoyment for me whatsoever, I'm happy to be as close to conventional as I can get. Just call me "Two Wires" 

Mark Diff posted:

My Tv is on 8-10 HOURS a day. And yes I do get 10-15 years out of it. His Locomotive may be 15 years old but really how many HOURS has it been run..maybe 5. Litigation isn't the answer or even worth it. I understand his frustration. Do you expect a part to fail when it is not in use 95% of the time?

Mark, did you bother to read my post above yours?  Yes, electrolytic capacitors are more likely to fail when they're not in use regularly.