Re: Parallel track power busses
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Duff or Polly,
That's almost correct as far as it goes, except for the statement about auto-reversing. Only ONE of the two blocks would need one. In fact, auto-reversers that are adjacent will not work happily together unless there is a piece*() of track between them that does not autoreverse.
Wouter
(*) volumes have been penned about how long a "piece" is, often when the subject is string. This is not the place for that discussion.
Assuming I am understanding correctly, polarity does matter with AC, but not the same way for train operation.
Let's consider two of the? six blocks for simplicity, the train rinning from left to right, and crossing from one block to the other.? The rails in each block are marked + and -.? Yes, for AC, they alternate, but at any instance of time, the the labels are as shown.
In this first example, as the wheels cross the gap, they connect + to +, and - to -.? No problem.
+ ____________________________________? ________________________________ +
- _____________________________________ _________________________________ -
In this second example, the wheels connect + to -, and - to +.? This is a short circuit.? And is what happens with reversing loops.
+ _____________________________________ ________________________________ -
- ______________________________________ ________________________________ +
If each block has its own auto reverse, things will correct themselves, and it may not matter.? However, if there are no autoreversers, a short will be detected.
This is how I understand it, given my limited experience with DCC.
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