Reverse Loop Wiring Block Advice Please

[SameAsItEverWas]

I’m finally after all these years getting around to actually building a real layout, N-scale by the way.  Current plan is point-to-point with a hidden reverse loop at each end.  Each reverse loop also contains a small double-ended staging yard.  There is about 2-3 feet of single track on either end of the yard that connect back to the visible layout.   The yard tracks are 3-4 feet long which is about the maximum train length I envision.  My question has to do with how to set up my reserve loop wiring block.  I’m a DCC newbie and plan on using auto-reverse loop modules.

Should the reverse loop wiring block be the whole loop including the yard and “approach tracks” on either side?  Will any locomotives that are “idling” in the yard care when the auto-reverse module swaps the polarity?  Or should I make the reverse loop one of the approach tracks which could potentially be shorter than my longest train.  I don’t plan (for now) on any exotic consisting with rear-end helpers or anything like that.

Any help would be, well, helpful.  Thanks.

[fwright]

SameAsItEverWas

Should the reverse loop wiring block be the whole loop including the yard and “approach tracks” on either side?  Will any locomotives that are “idling” in the yard care when the auto-reverse module swaps the polarity?  Or should I make the reverse loop one of the approach tracks which could potentially be shorter than my longest train.

I would avoid having a reversing section that is ever shorter than your longest train - especially for hidden trackage.  While you may successfully get away with a train longer than the reversing section, sooner or later you will run into the situation where both the entrance and the exit gaps are being shorted too close together in time for the auto-reverser to handle.  At best, the situation will require 0-5-0 intervention.

The reversing section must be utilized by every train that is being reversed, and only one train at a time entering or exiting the reversing section.  Other trains inside the reversing section boundaries, or "idling" engines are not affected - provided not more than one train/engine is attempting to cross a boundary at any given time.  For these reasons a reversing section that has only one entrance/exit track at the 2 boundaries is better than one with multiple tracks penetrating the boundary.

my thoughts, your choices

Fred W

[Doc in CT]

 SameAsIt ... the DCC mobile decoder doesn't care about the polarity of the tracks, its the short when a conductor (as in wheels) crosses the boundary between the reverse loop tracks and the mainline tracks in which the polarity IS reversed.  Idle locomotives can sit on the reverse loop if there is space regardless.

 Do read Allan Gartner's web pages on DCC;  there is also infomation on reversing loops at Digitrax  at Tony's Train Exchange and at DCCwiki.