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Discussion Starter · #1 ·
After 30 years in storage I am finally building my dream layout (given space contraints). This is the first time I have made blocks in a layout. I have a 1940's Lionel Bascule Bridge and isolated it from the rest of the loop as the instructions called for. My question relates to what is happening when the loco crosses from one block to the next. There is a bit of sparking from the loco pickup when it crosses. The first track after the insulating pin shows some pitting where this occurs. Is this normal?

Thanks for any help. This is my first post!

Gary
 

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Your transformers need to be in phase or your sparking at 24 volts.Clean wheels and track help reduce it. It helps if both are at the same throttle voltage.
The only other option is to have a transfer section that is powered by two transdformers and regulated with a toggle. The engine is offf when power is switched.
 

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Discussion Starter · #6 ·
track block continued

I now have learned what being out of phase means, thanks to you folks (with help from the glossary in my "Wiring Handbook for Toy Trains").

It's crazy to realize that I've had trains for so many years (mainly in boxes) and had know idea how much there is to learn.

This will be great fun! Thanks so much for your help. I'm very glad I found the Model Train Forum.

Gary

PS - when my ZW's were rewired obviously one was reversed. I had just purchased a KW on Ebay - that one doesn't have a ground plug, so I tried it. It still sparked until I reversed the plug!
 

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If the voltages aren't equal coming out, you'll still get some sparking. The test here is to connect a light bulb between the center rails of the two isolated section. It should be really dim or not lit. If it's bright, chances are the transformers are out of phase.

If you suspect the ZW is out of phase, reverse the wall plug. The stock KW did not have a polarized plug.
 

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Discussion Starter · #8 ·
solved

Thanks so much for the help. Once I turned the plug of the KW the sparking stopped. This is great. I just need to turn the plug on one ZW to get them in phase.

Gary
 

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Yes, they do. Each block is also powered by a separate transformer.
Big mistake. You're asking for trouble. As the loco goes from one block to the next, there is a fault current running straight through the loco's wiring. And no, the circuit breakers won't protect it. And no, having the two blocks powered by separate terminals on the same transformer isn't any good either.

The way to transition between blocks is to have both blocks on the same circuit. Once the train has crossed, you can switch one of the blocks to a different circuit. Yes, this means that you have to do a little toggle switching.
 

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Tons of people run multiple transformers for both conventional and TMCC, it shouldn't be a problem. What's the "fault current" you speak of, providing the transformers are phased correctly and their common terminals are connected?
 

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Lots of people drive without seat belts, too. ;)

The fault current is between the two "hot" connections. One block at V1, one at V2. There's potential between the two. What happens when you connect them?

For a graphic (if ill-advised) illustration of the risks, try this: take two in-phase transformers (or one multi-circuit transformer). Run a jumper between the two common terminals. Run a second jumper between the two hot terminals. Apply power and start twisting the knobs. Would you feel comfortable doing that? Because that's exactly what's happening when a train goes between blocks.

If you're interested in a more detailed explanation, Bob Nelson (username lionelsoni) has quite a few posts on the subject on CTT.
 

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The simpliest cure is add one track section and coast from block to block. It takes 2 to 3 to stop a train and one will isolate the contacts. If it stops in this dead zone rig it with a toggle switch for the save. The drawback is loosing the e unit position, if on.
It's not like you are "crossing over" every revolution, it is used to get from one loop to another. That is why I suggested the transfer leg.
 

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Hmmm, I am a newbie but divided a loop on my track into 3 blocks powered from 3 of the 4 outputs from my oldschool Lionel V. All the outer rails are common. I then run two trains on the same track. Works fine as long as I don't let 2 trains get in the same block. Once they are going I doubt there is 3v differential in the center rail.
Sure gets my grandson's eyes lit up. Also a great way to cause a major wreck if you don't pay attention.
 

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Lots of people drive without seat belts, too. ;)

The fault current is between the two "hot" connections. One block at V1, one at V2. There's potential between the two. What happens when you connect them?

If you're interested in a more detailed explanation, Bob Nelson (username lionelsoni) has quite a few posts on the subject on CTT.
Konga Man is correct here. No matter how close you get the two transformers
between blocks there will be a slight difference between the blocks. Now
if it is enough to cause a problem eh I dont know. But one has to ask this
question....

Why are you wiring it up this way? One transformer for one block and another
transformer for the other block...And having the engine "hop" from one
transformer to the other....Has me completely puzzled as to why?

Back in the day not too long ago transformer power went through a board
this board had the track plan on it and a bunch of toggles. Each toggle
would send power from the transformer to one block of track. As the engine
moved along you just turn on the next block with the toggle and turn off
the last when clear. Furthermore, if you had say two or more loops one could
just turn on several toggles to keep one loop always "hot". And then be
free to run the others. In this setup each transformer is "given" to a certain
engine and only that engine.

This completely solves the fault current problem all together. Of course the
different transformers are still phased just in case someone forgets to
throw a switch. Finally the board is also good for placing switches for your
turn outs. After a few run sessions you hand will just move along the pattern
with no problems.

Pookybear
 
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