I would suspect somethign liek that short is what happened. Cuttin one leg of a cirsuit is perfectly fine - that's all that happens with a light switch in house wiring even. Until something shorts and bypasses the switched lead. A short that simply allows power to get to the element will then burn the element up since I'm sure you didn't put smoke fluid in it if you weren't usuing it. That woudl take some period of time to burn out the element. A short elsewhere on that harness could make it immediately go up in smoke. Not sure what it needs so many wires for, there's the two wires to the heating element, then there's the blower motor that produces the puffs of smoke, 2 more wires. Feedback on the blower motor maybe - that would be 6. Unless the blower motor is actually a multi-pole stepper and needs multiple wires to drive it. Don't have any to take apart and examine.
Removing it makes room for a small speaker so at least some of the sounds would come from the boiler end instead of all coming out of the tender.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
rrinkerStrange it would still get power with the switch off, the switch is in line with the power to the thing.
There's SEVEN wires going into the smoke unit.
BLI_smoke-crop by Edmund, on Flickr
I tried to trace just how BLI has it wired and got lost. The reed switch is what makes the "Puffing" so that triggers the speed of the blower. The element gets full DCC track power. Even switched off the switch is only on one leg of the circuit, the other side is still hot. Maybe something shorted to the element.
The red and white wires here go to the under-cab switch, the seven pin connector plugs into a harness to the smoker:
BLI_smoke-crop2 by Edmund, on Flickr
You can see the magnet on the flywheel. The reed switch is on the bottom of the PC board.
I can't explain why but the smoke units get fried even if they are switched off. As I go through all my BLI locomotives and replacing the old QSI decoders I'm ripping out the smoke units, too.
Here's one way the switch can get bypassed! Although this isnt the engine that toasted the smoke unit, that was a PRR T1.
NYC_S2_BLI-wire by Edmund, on Flickr
This was found on a Broadway Limited NYC Niagara.
Regards, Ed
Strange it would still get power with the switch off, the switch is in line with the power to the thing.
I've seen ONE loco that has actual fairly realistic looking smoke, or steam at least - out of the stack in time to the pistons, out of the cylinder cocks when starting, and even out of the whistle when you blow the whistle. It actually looks good. It's also an incredibly expensive loco, in I think 1:32. I can only imagine how much smoke fluid you need to pour into this thing to keep it going, thankfully it's a larger scale that would more than likely be used outdoors because with that much smoke coming out, the coating on things would be really bad.
rrinker It's been at least a dozen other threads, but if I had one of these with the smoke unit, I'd have the switch in the off position 100% of the time.
I had a Broadway PRR T1 just sitting on a siding and heard an odd crackling sound coming from it. Before I could figure out what was going on the DCC breaker tripped. Here the smoke unit in the T1 was smoking, but not in a good way!
IMG_8095_fix by Edmund, on Flickr
Even with the switch off — I NEVER use any of the smoke units — the thing still burned up. Destroyed the decoder, too. I recently removed the smoke unit out of a NYC Niagara and replaced it with a mini-cube speaker .
NYC_S2_BLI-smoke by Edmund, on Flickr
Smoking models are a useless gimmick as far as I'm concerned. Doesn't look right, stinks and leaves an oily residue on the layout.
Good Luck, Ed
Depends on what kind of plastic. Polycarbonate and polypropylene both will be greatly deteriorated in contact with mineral oil. And it many cases, it's not the mineral oil, it's whatever else is added to it. Ever rated 'safe' plastics can have minor swelling in contact with mineral oil, which doesn't necessarily weaken the plastic, but it doesn't take much to change a press fit to a loose fit, which is what happens with the blower fans.
It's been at least a dozen other threads, but if I had one of these with the smoke unit, I'd have the switch in the off position 100% of the time. Or just disconnect it. Or I'd just get a DC version of the loco if they sold it, and put my own decoder in, given the prevelence of issues with the BLI electronics. The two I have are from when they also had PCM and those have Loksound decoders, and have never given me a problem. I think they need to harness some of Ken's marketing energy and use it to improve the quality of their circuit boards.
I don't think mineral oil will soften plastic.
There are two ways to ruin the smoke unit: run it completely dry, and overfill it. Or just not be careful enough when fillign it - the first smoke locos came with a little funnel, then they stopped including it. If the smoke fluid goes anywhere but actually in the chamber, ie, it seeps around the stack and down inside the mechanism, it can soften the plastic and cause the blower to stop working, meaning no more puffs of smoke.
BLI has problems, I have three units that have had electrical issues,
A steamer that has a non working smoke generator, another steamer that had its smoke generator turn into a flamethrower, and a diesel that lost ALL decoder functions.
I love their locomotives but their electronics are kinda lacking.
Steve
If everything seems under control, you're not going fast enough!
I believe I had addressed the OP's questions.
Do you have any additional useful information to add?
Do you use smoke units?
Thank you for your participation,
Happy Modeling, Ed
Smoke units are a lot like a lamp filament without the glass bulb. I don't use them. There have been several members here that have had problems with shorted BLI smoke units.
Nearly all of the BLI steam locomotives have a manual switch usually under the cab. There may have been a model or two with the switch behind the smoke-box front which can be carefully pried off using a non-marring plastic tool. I don't know about the recent diesel smokers.
You can also disable it in the decoder CV settings but if you reset the decoder you may forget to disable it again.
From the BLI Q&A:
Hello,
I was told by a friend that allowing the broadway limited smoke unit to run out of fluid can damage the system. Can the system be switched off by using a handset or do you have to remove the boiler of steam locomotives. Thanks in advance for any advice.
Regards Matthew Redden