Reverse loop with block occupancy detectors.

[LNERGE]

My layout has this as one of the reverse loops. It is currently working as one section between A and C as a reverse loop with a block occupancy detector at the A end. Train can pass between C and B on their way to a group of hidden sidings. It has worked well for a number of years. Most of this is largely hidden from view. I propose dividing it up into three sections, each with it's own detector. This is so i can send a loco to the hidden sidings with the aid of knowing when said loco has passed clear of the points. The three tracks would sumate as one to the entrance signals so only one train could get in at a time. It should work? Any thoughts? Further refinements will be a track lock over the points so they can't be moved with the track occupied and possibly and asymetrical brake section at the C end as that leads to the main lines. I've not tried ABC downstream of a reverse loop module but i can see no reason why it shouldn't work. Again any thoughts?

 

 

Edited December 27, 2020 by LNERGE

[WIMorrison]

each one of the feedbacks you create within the reverse loop area will needs its own detector with auto reverse model and the challenge you will have is that the reverse loop module is liable to draw current and show occupancy whether a block is occupied or not. The LS Digital 5410 is the only module I have found that doesn’t can go after the occupancy detector and that doesn’t show occupancy. 
 

the other option would be to have one auto reverse module before the occupancy detector and feed the track sections from the outputs of the detector module. Clearly the occupancy detector module needs to be able to accept reversing polarities.

 

Personally I would be trying to design the layout in a way that has a section of track long enough to handle a complete train and make that auto reversing and treat the rest of them as normal track.

[LNERGE]

Unfortunately this is a retro fit to a large(ish) existing layout so no room for luxury with being able to hold a complete train in one section of the reverse loop. I plan to keep everything downstream of the reverse module. The only real change is adding two more sections. It currently works succesfully with one block occupancy detector.

[WIMorrison]

Good luck, please let us know how you get on.

[LNERGE]

I fell at the first hurdle. The baseboards involved are lift out and the plug couplers are almost full. A delve into the bits box produced a plug coupler of the same configuration as the existing ones.. I could colour code them i guess but it's not in my nature to provide anything that can be cross coupled because if it can happen it will happen.

[LNERGE]

I’ve spotted a quick cheat while I investigate larger plug couplers. 
 

Track circuit DB2 has been created using the part of DB1 that covered the points and the controls and indication on DB1 track transferred to DB2. The boundaries of G track have changed taking it nearer the toes of 66 points. The shortened DB1 track will be added to the diagram as the next phase. 

 

At this stage it appears that two block occupancy detectors work quite happily downstream of the reverse loop module.

Edited December 29, 2020 by LNERGE

[Grovenor]

I'm completely lost by your diagram, there appears to be several insulated joints where the polarity always reverses at the joint and will cause a short when any train passes.

[LNERGE]

2 hours ago, Grovenor said:

I'm completely lost by your diagram, there appears to be several insulated joints where the polarity always reverses at the joint and will cause a short when any train passes.

In the original post the rails are shown red and black swapping over at joints of the block occupancy detector sections. The pole change from the reverse loop module occurs between the brackets at A and C with an additional exit at B. Traffic between B and C and vice versa doesn't call the reverse loop module part from the first time after a train has left via A.

[Grovenor]

The insulated joints shown at the toe of the points, for example has a polarity change that is hard wired as the red is wired to the red and the black to the black, no polarity change switch involved, so any train crossing that insulated joint will short.

[LNERGE]

I'll redo the drawing tomorrow. What is there works well. My drawing could be better.

[John ks]

Is it possible to move the reverse loop so that C- B in no longer inside the reverse loop

I am assuming the circles on the black DCC feed represent the Detectors

 

If the length A-C is required to fit a complete train then move the other end of the return loop to D 

the section D-A can have it own detection  & be inside the return loop

 

OR

 

If the loop(B-A) is long enough then the section D-A will be outside the loop 

 

 

John

[LNERGE]

Revised drawing. Track circuit G had to be removed from the reverse loop due to constraints with the existing plug couplers. The reverse loop has worked well for years. It is the issue of multiple block occupancy detectors downstream of the reverse loop module I was unsure of. So far everything looks to work. I intend to add the revised track circuits to the illuminated diagram today. 

Edited December 30, 2020 by LNERGE

[WIMorrison]

On 27/12/2020 at 20:48, WIMorrison said:

.... 
 

the other option would be to have one auto reverse module before the occupancy detector and feed the track sections from the outputs of the detector module. Clearly the occupancy detector module needs to be able to accept reversing polarities.

 

...

 

I think that what you are doing is the second method of implementing a reversing area within the layout that I previously described

[LNERGE]

1 hour ago, WIMorrison said:

 

I think that what you are doing is the second method of implementing a reversing area within the layout that I previously described

Yes indeed. Works now complete apartt from the abc module on G track. I have a rather impatient 7 year old waiting to try it all out.

[LNERGE]

We had a good operating session last night and tested the new arrangements. 
 

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