Maybe we need Mythbusters to look into this and see if they can reproduce it.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
I've had an Atlas GP40-2 take off on me once, when I powered my NCE PH Pro on. Fortunately, it only shoved a McKean boxcar onto the ground (minimal damage) before I turned the system off. Be aware, when the loco takes off, it takes a moment for the sound to catch up to what the loco is doing, so you might not hear a loco going full speed, but you will see it!
I have made it a habit to not spot a loco where it can run off the end of the layout; either right at the end of a spur (so it won't gain too much speed before leaving the end of the rails), or I at least set a turnout against it so, hopefully it will derail (or keep it from going too fast, so I can grab it) before making it to the end of the layout. I never thought of a club layout with a hundred or more locos on the track; better say a 'no-runaway' prayer to the DCC gods before powering up (then check hidden staging).lol
I only fried one decoder, a DH123(?). While checking my installation on the program track, an unstripped stray headlight wire hit the rail just right then I saw a little light show going on under the shrinkwrap, followed by a small puff of smoke. It only took about a 1/2 to a whole second before I moved the wire from the rail; but that's all it took.
I heard if I send the decoder back, and if I'm lucky, they might replace the decoder for free. Of course I will order several more decoders to sweeten the deal for them...and hope they are in a generous mood!
http://delray1967.shutterfly.com/pictures/5
SEMI Free-Mo@groups.io
He said the loco took off on its own. That tells me there was a short to that decoder as he said other locos were on the tracks i believe and they were fine. Probably for some reason short or not ,power to the decoder provided voltage for catastrophic failure not only smoking decoder but burning it. Send in for warranty replacement if less than a year old. TCS are great guys to deal with. Steve....................of course to he could have had out of control syndrom then the final short and burnt decoder at the end of its travels.
Modelling HO Scale with a focus on the West and Midwest USA
I still suspect the problem is related to it being stuffed up under the board.
Dave
Lackawanna Route of the Phoebe Snow
I think TCS is just trying to deflect blame from their decoder. We have been using the NCE PowerHouse Pro 5 Amp system on our large HO scale club layout that is divided into five power districts, for several years and have never had a similar runaway or decoder problem.
Right now, we have close to 300 decoder equipped locomotives among all the club members (not all on the layout at the same time, obviously) and never has one burned out like the OP's decoder.
I believe the fault was not in the decoder or in the DCC system, but in the installation of the decoder.
Something else that has not been mentioned is the possibility that through a wiring error the OP wound up with AC line voltage on the track. That would certainly cause damage.
trainboyH16-44 The guys at TCS are blaming my command station...I'm not sure I buy it, seeing as there were other locomotives on the track at the time, with the same decoder in them. I did the quarter test just to make sure, and power shut off as I'd expect it to.
The guys at TCS are blaming my command station...I'm not sure I buy it, seeing as there were other locomotives on the track at the time, with the same decoder in them. I did the quarter test just to make sure, and power shut off as I'd expect it to.
Ridiculous !
I'm not buying it either.
I have the same system you do, an NCE 5A PH-Pro. I have never experienced such a problem.
Alton Junction
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Building the CPR Kootenay division in N scale, blog here: http://kootenaymodelrailway.wordpress.com/
Running into a wrong-way switch should not fry a decoder like that. The short is across the rail pickups - wait, wrong word, THROUGH the rail pickups, ie right side of lead truck to right side of rear truck. If anything, it would fry the circuit board trace or the wire connecting the front and rear truck on the side of the short. I suppose it could happen, just seems very unlikely. I know Ken used to BBQ decoders frequently, but I think that was internal shorts or pickup to motor shorts, coupled with inadequate feeders and the use of an MRC 8 amp booster. The movement may well have been a sympton rather than the cause. I've never had a runaway like that, but I do turn off DC with CV29 in all my locos. The times I HAVE seen it, it was always during system startup, ie, when the track power comes up but the DCC signal isn;t fully stabilized, allowing the decoder to think it sees DC.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
If you go back to the original post, we know what happened. The engine took off and derailed, causing a short that burned out the decoder. The real question is why the engine took off like that. Here's a link to Tony's Trains that might have some info:
http://www.tonystrains.com/tonystips/2011/032211.htm
Looks like an M1. M4's have a purple and green wire for F1 and F2. For whatever reason, TCS uses clear shrink wrap instead of their usual blue. Maybe it's thinner than the blue stuff.
If it was wedged up under the circuit board, likely it wore away the shrink wrap and allowed the thing to short on the frame. Has to be a pretty catastrophic failure to burn up that bad. Not sure why someone would do tha,t my 44 tonner has an MC2 in it, which is clightly bigger, since it has a connector on the decoder like a smaller version of the 9 pin JST connector, and it fits fine right on top of the factory board.
Probably can get it replaced, the TCS warranty is 'goof proof' so even if you fry it yourself the first replacement is still covered.
If it was under the board, the entire conductive engine frame was against it, and there would be no airflow to cool it. If the cover melted, the decoder would short out against the frame.
More information - it's not a factory installed decoder. I didn't install it either, but it's either a TCS M1 or M4. It wasn't on startup, either, so it's not the problem I've heard about to do with analog mode. The system I'm using is an NCE 5A power pro, and I had no problems with any of my other locomotives. I've run this locomotive before without trouble.
I don't know the sequence to emergency power down the layout, but as it zipped away from me I certainly mashed emergency stop a couple times! As it was going full speed, I didn't have much time to do anything.
The decoder was mounted under the factory board, but in a spot where there are no conductive materials on the bottom of the board.
-sigh-
I'll have to agree. I've toasted a few but have never seen one this bad. It suggests some sort of dead short either external or internal to the decoder. At least now you have a chance to replace it with a decent decoder.
Joe
Try to take a picture of how the decoder was mounted in the loco.
That does not look like a Bachmann on board decoder.
I've NEVER seen a decoder burned out that badly. Usually it's just a small hole or black spot where only one component on the decoder overheated and burned out.
Just a WAG, but I'd say bare metal contacts on the bottom of the decoder were touching bare metal spots on the circuit board into which it is plugged, creating a dead short, if the decoder was not totally covered with shrink wrap.
There appears to be a clear plastic covering on top of the decoder, which tends to indicate that it is not a Bachmann decoder -- theirs have black shrink wrap.
If the circuit board had both an 8-pin and a 9-pin connector with a dummy plug in the 9-pin jack that was not removed, that is what created the short circuit that fried the decoder.
The LION has never burned up a DCC unit simply because the LION does not have any DCC. But him has started small fires on his layout because of short circuits. His power supply is 15 amps, a short circuit with a speed resistor in the circuit will draw 5 amps and set the resistor on fire, but will be no where near close tripping out a breaker.
LION still has work to do on that project, but him has installed buttons all around the layout. These will cut off the power to all of the tracks (and the Standard Clock too.) If I am working on something over here, and here a train derail over there, I can push the nearest power cutout and then go over to inspect the problem.
LION wants to put a 12V automobile brake light in series with the power. A locomotive or two will not draw enough current to allow the light to illuminate, but a short will light the bulb, and tell me where the problem is. It will protect the circuits until I can work on them. Because I run so many locomotives all at once, I need a lamp for each power district, otherwise the number of locomotives will draw enough current to cause the lamp to come on.
ROAR
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
I've had a Bachmann take off, too. It's one with a Soundtraxx decoder in it. Someone has suggested that you need to disable the DC Compatability Mode on it to prevent this.
Does your throttle have an Emergency Stop and Power Down on it? If your throttle is in your hand, that's going to be a faster way to shut things down than running around the layout. If you're not familiar with the sequence, it's a good one to learn.
It takes an iron man to play with a toy iron horse.
I gotta say, I have been the victim of more than one fried decoder in the past, and I have experienced the smell of burnt electronics, but I have never seen what you have just shown us. When I have had a fried decoder in the past, a visual inspection has left me wondering which component had burned out because the circuit board looked fine to me.
Was this your first run with the loco? Is this a factory installed decoder?
**Points out the obvious** I'd say you have a fried decoder. I assume this is a factory installed Bachmann Decoder? (Probably made for Bachmann by a 3rd company) I've read elsewhere in the forums that Bachmann decoders are hit-or-miss at best. Was this the first time this loco had been run? What DCC system are you using?
Brad
EMD - Every Model Different
ALCO - Always Leaking Coolant and Oil
CSX - Coal Spilling eXperts
In the middle of the grand festivities after finally having all track laid and gleamed...I started to run my H16-44 (bachmann) and it took off at full speed with the throttle set to 0, not stopping until it ran through a reversed turnout and shorted the layout. By the time I got there it was already dead, with the smell of burnt electronics hanging in the air.
Can you tell what happened?