How can I set up automatic turnout control for a reverse loop?

[Mark W]

I'm ready to lay track on Middle Loup, but I'm stuck on the electronics.

I'd like to set it up so that a train can enter and exit automatically (on the main line only (the outer most track)) without any manual adjustment required, meaning the first three turnouts will automatically flip when the train comes back around.

Ideally, this will be possible regardless of what the initial route is, so I'm thinking if there are 4 detectors, one about where each of the 4 main tracks cross the first module, then when the train hits that detector on the exit route the remaining 'downstream' turnouts align accordingly.  The remaining turnouts will be manual and not set-up for automatic alignment.

Does that make sense?  Is there any commercial DCC controllers that can accomplish this, or an easy way to build one?

[bdennis]

Mark,
Hmm.. If it had been 1 turnout then a PSX-AR with turnout control will do the job.. (From DCC Specialties)
But with the multiple turnouts it is more like multiple blocks with 2 x DS64's JMRI running that can detect the location of the train and then throw the turnouts needed.

Or.
a TC64 from RR Cirkits. You could set up multiple blocks for detection that when sensed they could fire the turnouts needed.. But probably still need JMRI to manage it.

I have used the PSX-ARSC on my reversing loop that had 1 turnout with great success.

[railnerd]

Seconding what bdennis said, go for the PSX-AR.  That is what we use the SVFMN "Wye Knott" module.

See page 4 of the document here: http://dccspecialties.com/products/pdf/man_psxar.pdf

-Dave

[bdennis]

As mentioned the issue with the PSX-AR is that it will work with 1 turnout but not 4 or 5..
So due to the complexity and the number of turnouts this situation is going to need something else..

Just for reference, while were on the subject of the PSX-AR.. I have the PSX-ARSC. (the snap coil version) I have connected it to a old H&M Snap coil machine.
I place the insulating joiners for the reversing section at the frog end of the Atlas Code 55 turnout.
When the PSX-AR detects that the polarity needs to be reversed it does it in a split second and also throws the snap coil machine. All this happens BEFORE the loco gets from the insulated joiner on the frog end of the turnout to the frog it self (even at speed) so there is no issues with sensing then reversing and throwing the turnout before the loco gets to the points of the turnout.!

[Writhdar]

I use Azatrax IR detectors ( http://www.azatrax.com/ir-model-train-detector.html )and DCC Specialties PSX-AR for two fully automated reverse loops.  For both, multiple turnouts are triggered.   The Azatrax units are very easy to install, set-up & use (I do "across the track" mode) and are relatively inexpensive.

The reverse loops are at the ends of my layout.  The entry/exit for each loop is a single turnout ("throat" turnout).  Shortly before each reverse loop, the layout goes from double to single track.   So I also want the turnout at the "double-to-single" location to have its aspect changed for a train exiting the loop.  The IR detector is at the extreme end of the loop to ensure a train is past the "throat" before triggering occurs.

Prior to using the IR detectors, I used J4-3 & J4-4 (occupancy in the reverse loop section) on the PSX-AR to trigger the turnouts --- J4-3 to the Digitrax DS64 Common+ and J4-4 to the "S" input for the turnout.  The IR detector output is also connected to DS64 Com+ and "S" of the turnout(s) of interest.  The "throat" and "2 to 1" turnouts (by each loop) are on the same DS64.

The IR detectors are much better for triggering because (a) train length is less of an issue, and (b) the PSX-AR threshold detection current level had to be raised several times to avoid false triggering.  When I used the PSX-AR J4-3&4 for triggering, the distance between the divergent leg of the "throat" turnout and the start of the reverse section was too short.  With the IR detector, this is no longer an issue.  That is, a train can enter  regardless of the turnout's aspect. 

Dan

[Mark W]

Thanks for the input everyone.  Sounds like the PSX-AR1 is the clear winner. 

The idea of automating the exit alignment of the first three turnouts has been reduced to only the first turnout.  This will allow me automate the main line when I'm running trains alone, yet not enough automation to let peoples attention slip when things get hectic at train shows. 

[bdennis]

Mark.
If your going down the PSX-AR path, just make sure you order the right one.
There are a number of options.
As I use a snap coil machine I have the PSX-ARSC.
The base PXS-AR looks to have the stall motor function by default. So you just need to make the isolating joiners far enough back to ensure that it throws the turnout in enough time.

[rsn48]

I am in the process of doing the same thing with a Wabbit (two Hares) in conjunction with tortoise turnouts and On Guard auto-reversers (OG AR).  What I recommend is calling the techie guys at Tony's Train Exchange (which I did and review what you want done).

I bought the Wabbit as it is two Hares and I have a reversing loop on my lower deck and there will be one on my upper deck so continuous running when I am alone, which will be most times.  So I can have a train running while I am switching just to make things a bit more interesting and fun.

The train will come in on the main on the lower deck from above, hit the trigger track which will set the auto throw working controlled by the Hare.  The train will go through the turnout and have the same thing happen when it comes back along the loop.