Melted wires inside passenger cars

I had the exact same problem with my Lionel heavyweight cars.The wires rub against sharp edges of the grounded chassis and start to short out.Or by derailments.I re wired them with 16 gauge zip cord.Be careful how you route the wires.Haven't had any further problems.Also FYI these cars typically pull to much power.I only run 2 of the 4 bayonet bulbs to cut down on the draw.It is still plenty of light IMHO.Hope this helps,Nick.

The wires could also have been melted by a derailment, where one pickup was on the middle rail and the other pickup contacted the outside rail.

That type of meltdown can be prevented by wiring the lights differently, in a number of ways.

Unfortunately, the cheapest way to wire lights is to hook both pickups together, like all the manufacturers do.

I don't remember the specifics, but I believe one of Jim Barrett's Backshop videos covered a work-around for some rollers on K-line passenger cars that could cause problems.  (I think the work around was to install a flexible wire to jump around a spring that was not the best in terms of low resistance electrical properties)

I' can't say if they were the ones you are referring to or not, but maybe this will jog someone's memory a little.

Good luck.

-Dave

The lightweight wiring inside the passenger can carry, potentially, the electrical load of an entire train, or whatever might be track powered(possibly 10-15 amps depending on the layout and equipment) in the adjacent block, if its two pickups are bridging two blocks with different voltage settings..

Boxcar Willie actually wired one of the rollers this way that he sent me. In addition he gave me extra wire to do the same with the others. So I have done hat to the new ones.

• The older K-Line cars from the late 80's - early 90's were not designed for 18 v command control. I have seen the insulation melt off the wiring due to excessive heat.

The wires melted because of a short or too much current to the bulbs. If too much current to the bulbs, use lower power bulbs. If a short, The wire acted as a fuse. I would use the same size wire as the original for good fuse action. It seemed to work OK the last time.

The main culprit can be a lightning strike.  I have repaired numerous passenger cars for people with the same conditions.  The first question I asked them was "Did you have a large tree near the house get struck by lightning?"  Even a strike 20 feet away can fry the wires.  Surge protectors have limited ability to protect against this.  The best insurance is to unplug the transformers when not in use.

Classic reason for melted wires in the cars is a derailment where the breaker doesn't trip.  I put a PTC in my LED upgrades between the pickups to prevent that.

SUGGESTIONS FOR WIRING OF TRACKS AND LIGHTED CARS.

On my layout every "block" is protected by an individual circuit breaker.  Each block uses an individual circuit breaker rated at 3 amps. This limits the current to the block.  If a derailment occurs and a short circuit exists the block is protected while other sections (blocks) of the layout are not affected.

Also all my lighted passenger cars are converted to LED lighting.  This reduces total the current required when several passenger cars are on the track at the same time. Protecting the wiring inside passenger cars would require installation of an individual fuse in every car.

I also have other circuit breakers protecting both the inputs and outputs on my MTH DCS TIU.

Separate fuses installed in each engine would also be recommended.

I'm not sure how they were run prior to getting them. The cars look great and I am assuming they were run conventional because I am pretty sure he did not use any type of command system.

I posted a photo of the rollers on another thread.

I just didn't want to repeat the same problem. It almost looks as if these were run a lot and for longer time periods. In addition they are or at least do not look as robust as other rollers.

LED's are certainly a consideration in the future.

Thanks for all the help and or suggestions.

Can we say overkill and probably not all that practical? 

Since you converted all the passenger cars to LED lighting, adding the PTC during the process is a trivial step!  Adding a ton of circuit breakers all over the layout for a large layout is a much larger undertaking!

One thing that erodes rollers is current passing through them.  LED's will reduce the current to a negligible amount and probably greatly increase the roller life.

Moisture content of the metal contributes as does the spring.  Since the spring on K-Line carried current and would weaken, the roller can bounce.  Each bounce produces a spark.  The spark is the arcing and it is like welding and so some material is consumed on the roller.  Once a groove is established and the car is still used, you just consume roller until it splits.   G

Right, and the current passing through the roller is what creates the spark.  Cut the current by a factor of 20 times and you get less sparking and less erosion.  Also, the much smaller currents running through the spring help with the life of the spring as well.  The reason the spring weakened was it got hot from the current, the LED conversion removes a vast majority of the current.