Does each reverse loop require its own Auto-Reverse module?

[Night Train]

....or will one reverse module sense the reversing short-circuits for all of the reverse loops (3) on the layout?

 

[ianacole]

I believe they are one for one, so you'll need 3.

 

[Selector]

I think that, theoretically, a reverser can work three reversing sections, but it can't reverse any two simultaneously, and that is the nub of it. If you could guarantee you'll never require it to reverse two gap pairs that are not already on the same reversing segment, you should be fine. The problem will come when it detects two shorts at the same time, and not in the same reversed segment. So, the short takes place as soon as a metal wheel bridges both sides of any one gap, and if that gap can be handled quickly by the reverser, you are okay. If you have trains crossing the gaps on any two reversed sections, you could get the reverser confounding itself trying to clear one problem while creating another conflict at the other reversed segment.

Accordingly, it is best to make them look after the gaps at the ends of only one segment. That way, when it detects a short and modifies the polarity there, it actually only solves the problem and doesn't swap it for another elsewhere.

 

[TrinityJayOne]

I'm going to encounter a similar problem with one of my loops that connects back onto the main at two different locations. It will work fine as provided I don't run a train with helpers of such a length that two engines are simultaneously entering and leaving the isolated reverse loop.

For your situation I'd play it safe and just run an auto reverser per loop.

 

[cv_acr]

I think that, theoretically, a reverser can work three reversing sections, but it can't reverse any two simultaneously, and that is the nub of it. ... The problem will come when it detects two shorts at the same time, and not in the same reversed segment. ... If you have trains crossing the gaps on any two reversed sections, you could get the reverser confounding itself trying to clear one problem while creating another conflict at the other reversed segment.

Exactly. Each reversing section can only have one train entering it. If you get two trains hitting opposite ends of the reversing section, it won't be able to reverse it properly as each train is basically requiring it to be a different polarity so it can't switch it. Result = dead short.

So basically you have to all but guarantee that only one train can ever be crossing the gaps on any particular reversing circuit. If you have three completely separate reversing sections they need three separate circuits.