I have a reversing loop and a wye connected to one (PSX) auto reversing breaker. I wired it with a DPDT switch such that it should only be used in one situation or the other. It’s a medium sized layout usually just operated by just me (I.e. lone wolf concept) so I am aware of what’s going on. That said, if I should get to an “operation” type of situation then it might be suspect to problems. So, if you are the only operator then one AR should be fine. If you plan to have more than one operator . . . . .
I'd just add, be sure to get an auto-reverser that is adjustable. Several people over the years have posted here that they bought ones that were not adjustable, only to find that they didn't work in their layout situation.
Yeah, I would put the extra money into a second autoreverser. They can be reused on your next layout, and will let you upgrade to a second engine without worrying about where they are on the layout.
Autoreversers are meant to simplify your layout, not complicate it.
It takes an iron man to play with a toy iron horse.
Being scrupulously technical, you can have two trains using two different reversing sections controlled by a single reverser...IF.....IF...and only IF...there will never be the event where both trains have a metal wheelset crossing gaps at either ends of those two reversed sections simultaneously. That's the trick...simultaneously, or within the triggering timeframe setting one imparts to the detection of shorts, a setting that is variable on reversers. Even if they were within a half-second of each other, the reverser would detect and reverse the phase disparity at each gap and the decoders would not so much as burp. Decoders don't mind the phase reversing under them if it's done in milliseconds, and don't even mind two or three quick reversals in succession. It's the longer phase conflicts that make the systems shut down because they'll read them as faults, or the cumulative pauses when the tracks are unpowered begin to overcome onboard power storage devices and the decoders will shut down. For QSI decoders, that meant a full startup sequence again in some instances.
What this amounts to is that, unless you are prepared to use math to derive a probability table based on the numbers of cars of all possible types, and in all possible combinations, that can sit within the lengths of the reversed sections, and where no two axles will cross any of the four gaps simultaneously, it's all more bother than it would be worth to most of us. Reverse each section with it's own 'chief'.
A diagram is always helpful in situations like this.
You CAN use one autoreverser for two reverse sections - so long as there is NEVER any chane of trains using both loops at the same time.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Wiring my layout I have found that I have two locations where I believe I need Auto reversers or do I? As the track disappears into the layout and returns the two tracks have reverse-polarity also after this point the track does a ballon in around The yard... Can I or have you ever added extra length to one reverser to run two locations? I have a small layout so the locos should only cross the gap at a time!