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Luckily there was no coal in it. I bought a used Lionel cement coal dock (the round one). It appeared new in the box but close examination showed it had been used. The day finally came when I wired it into the accessory grid on my layout. It lit up all nice and blinking LED on top. I turned my back and walked over to do something else. Turning back around. the **** thing was on fire! The extremely thin wires that feed all the lights and LED had gotten red hot and caught the plastic on fire. It was literally in flames!

Naturally I yanked the feeder wires out, hit the master switch and then held the tower under an open faucet a few steps away. Catastrophe averted. But why was this a problem? Looking underneath, it looks like one of the bulbs developed a short (the wires to that one bulb are melted where wires going to the other bulbs look normal--this is shown in the pix but it is hard to see).  Those wires are so fine that it looks like they might be a bit small for this application. That coaling tower has six bulb lights plus the blinking LED, all wired in parallel--and the wires to EACH BULB are the same size as the wires feeding everything. So I dunno...

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This is a good wake up call for me. All I have is one circuit breaker guarding the whole accessory grid. Now I am going to break down the protection into smaller bites. My grid uses 6 feeder boxes and so I'll put some form of protection (circuit breaker, fuse or ???) at about 2-3 amps at each box. I was thinking about PTCs but I think they get hot, don't they?

Well, Happy Thanksgiving to all! I am thankful I didn't burn down the house!

Don Merz

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Last edited by Rich Melvin
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I had a Life Like accessory do that once - was fine a number of years and then one day - poof.  Also had some RR lantern Christmas lights randomly catch fire one time.  Luckily they were decorating a metal winerack and not a Christmas tree!  I dont trust anything with fine wires now - new LED accessories all look nice and the bulbs stay cool but some poor, tired person in a foreign country is wiring them up and i'm not sure their heart is really in it.

@Farmall-Joe posted:

I dont trust anything with fine wires now - new LED accessories all look nice and the bulbs stay cool but some poor, tired person in a foreign country is wiring them up and i'm not sure their heart is really in it.

Joe,

You're on the right track but the work of the poor tired person is not as critical as the fact that a small gauge wire ends up being used as a fuse.  As John alluded to, this thin wire can be placed unintentionally across the power supply due to an inadvertent short circuit.  This situation makes it such a fuse, and since the wire is not professionally and properly designed to be a fuse it could easily burst into flames.

To avoid this, also quite correctly implied by John, the solution calls for using a fatter wire (which won't overheat and melt) in series with a real fuse, or a PTC (which will safely open the circuit).

Last point:. If the poor tired person wires this corrected version up with an inadvertent short circuit then the fuse blows, or the PTC scales back current flow, and there's no heat and no fire.

Mike

Last edited by Mellow Hudson Mike

Why I test every accessory on my workbenchs either in the house or garage. If I don't like the look of wiring, I'll redo it myself and put low amp fuse on it, starting at one amp, and test to find the current draw then go one amp higher, so if the accessory malfunctions, it should pop the fuse. I also have fire extinguishers in my train room and by both workbenchs besides kitchen and bedroom. Better safe than sorry!

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