Need help, identify the reversing loop for me

[rsn48]

In the pic below is a fairly accurate track plan of track already installed.  Distances and curves may not be portrayed as they are, but from an electrical stand point of view, this plan is accurate.

The outer mainline, the track closest to the wall and isle is the mainline, and from the beginning to the end is roughly a 39 foot loop.

What I am hoping some one can provide, or group consensus, is where should my auto reversers go? 

[C855B]

Maybe take a look here: https://www.therailwire.net/forum/index.php?topic=30576.0

Pretty similar to your problem.

[eric220]

The length of the reversing section should be longer than your longest train.  Logically, if it fits, I'd say use the section between the crossovers on each side of the loop.  You could expand it all the way out to just left of the crossover at the upper left near where the double-tacking starts on each leg.

[rsn48]

Eric, I was thinking your second suggestion as then two trains could be within the loop.  The trains are roughly 8 feet long and that outside mainline could easily handle them.

[PAL_Houston]

The reversers are required at the top, where the trck looks trapezoidal.  The reason is that electrically you are connecting oppositepolarities across those turnouts.

[nkalanaga]

As Paul says, both of the crossovers at the top complete a reversing loop. so you need two reversers.

[peteski]

Why not just gap the tracks on the inside of the crossover and use single reverser to power that loop?

[nkalanaga]

That would also work. 

I was still thinking DC, and would probably use DPDT switches or relays connected to the crossover switch machines/groundthrows.  With DCC and auto reversing there's no reason the entire mainline couldn't be switched with one device, and that would be cheaper and simpler.

[wcfn100]

Can you do this.



And then like Pete said (so he doesn't have to tell me he said it  ), just power the loop with the reverser?

Jason

[peteski]

Can you do this.



And then like Pete said (so he doesn't have to tell me he said it  ), just power the loop with the reverser?

Jason

Wouldn't (what I said) be even simpler?  Moving the block further to the left, before both switches on the left crossover.  Only tracks would need to be gaped (not three).  Maybe I'm just missing something obvious... 

[wcfn100]

Wouldn't (what I said) be even simpler?  Moving the block further to the left, before both switches on the left crossover.  Only tracks would need to be gaped (not three).  Maybe I'm just missing something obvious... 

Maybe, honestly I didn't know what "inside the crossover" meant exactly.

If those turnouts are back-to-back I'd probably avoid gaping the track there, but that's me.

Sometimes it's also simpler when all the cuts are on the same line.  Again, just me.

Jason

[rsn48]

Just to clarify, though I don't think it will matter, but if I number the turnout to the right of the red line on the trapezoid at the bottom, number one and the turnout at the top of the trapizoid to the left of the red line number two; then turnouts one and two will be auto thrown (also will be able to throw manually) by a Wabbit (one Wabbit = two Hares).  I want continous running when I am by myself, the upper level will also have a reversing loop and it will be auto thrown, auto reversed as well.

[PAL_Houston]

As Paul says, both of the crossovers at the top complete a reversing loop. so you need two reversers.

Not so.  You do need to gap both of the links.  However, you have a choice as to gapping either the top main (on both sides of the turnouts to the links), or on both sides of the bottom main (on both sides of the turnout to the links (assuming your layout continues eastwards from 'the trapezoid'.  The particular 'best' places you place the gaps may depend on how you envision operations and what are your train lengths. 

By 'train length' I mean either head-end power, or if you are using either helpers or resistive rolling-stock (cars with lights, wheel resistors, or FREDs for instance) the full length of the consist.

[peteski]

Maybe, honestly I didn't know what "inside the crossover" meant exactly.

If those turnouts are back-to-back I'd probably avoid gaping the track there, but that's me.

Sometimes it's also simpler when all the cuts are on the same line.  Again, just me.

Jason

It made sense to me when I wrote, but you right, "inside the crossover" is not very clear to someone else reading my reply. 

Here is what I meant:

[wm3798]

You don't need the reversing bit to be as long as a whole train.  On my layout, the reversing section was about 3' long, long enough to comfortably handle the biggest lash-up of locomotives I could imagine using.  The engines enter, the section aligns the polarity, then off they go.  This was especially useful because my loops were multi track staging yards.  I didn't like the idea of 6 trains getting their polarity switched all around every time something came or went in the yard.  By making the polarity swap section on the outbound side of the loop, trains entering staging weren't threatened with a potential electrical hiccup during entry, and trains exiting only activated the reverser one at a time.  If you use metal wheels, you might want to stagger your gaps so as not to cause a reversing "event" at each axle...

Lee