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Discussion Starter · #1 ·
So I dove in and hooked this up per instructions. Worked good in both directions then the engine would stop at only 1 gap. Main power on one side and loop power on the other. Then it would be ok a few times and stop again. The power on each side is working so I don't know why it would stop. Why does it work/not work sometimes?? I thought the AR1 took care of this.
Thanks
 

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What you report is very unusual.

First, a short explanation of how the AR1
works. When the front loco wheel spans
the insulated joiner there is a short circuit.
A very fast acting relay reverses the phase
and the loco should proceed without a pause
or even blink of it's light. When it reaches the
other end of the isolated section again there is
a short when the front wheels span the insulated
joiner and again the AR1 matches phase to the
main track.

The first question I have toward a solution is
what turnouts are you using? Some are
power routing while others use a powered
frog....also there could be defective
point conductivity.

You may be able to test the functions of the
AR1 by using a metal piece to span the insulated
joiners as you observe a multimeter set to AC
reading the isolated section. You should not
see an interruption or change of voltage. Do
this again at the other end of the isolated section
and let us know what you find.

Don
 

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Discussion Starter · #3 · (Edited)
On this loop, before and after I have Peco Electrofrogs. I have power at the ends and 2 diverting tracks. The power is getting to each section. It's crossing the gap that stalls the engine.
Just for kicks, I'm going to really clean the loco wheels and see what happens.
The track is nice and clean now, too. So we'll see
 

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It sounds like it's not always reversing fast enough. I'm not real familiar with auto reversing units, but I do know the amperage setting of the reversing unit and the amperage of the DCC system have to be right, in that one must be higher than the other for the unit to work properly.
I think the trip current of the reverser must be lower than the amperage of your DCC system, but if that's not correct someone please chime in.
 

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Discussion Starter · #6 ·
Cleaned the wheels, still no go. Worked back and forth once and no more.
Tried the adjustment screw and still no go.
Going to my LHS and call Digitrax. (He has a hotline)
Very frustrating because one end is fine every time and this other end is a stinker.
 

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Electrofrog turnouts must have insulated joiners
in both frog rails to avoid short circuits. It may
be the changing phase of the frogs and frog rails are causing
your problems.

Don
 

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The reason it works at one end and not the other is that one end has the correct and matching phase. The place where it stalls is the gap where there's a conflict.

Digital reversers only correct conflict once during any passage through a reversible section. If there's a conflict at the first gap, there isn't one when it leaves the reversing section. If it's okay at the first gap, it'll be wrong at the far gap. Only once.

As far as I know there are two adjustments to consider. One is to the trip current, while the other is to the time it takes to alter the phase. One, or both, is going to solve your problem. If your engine works around the rest of the rail system, your problem isn't dirty tracks or dirty tires.
 

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Discussion Starter · #9 · (Edited)
As for my turnouts, I have the proper insulating joiners.
I talked to Digitrax today and the gaps have to deep enough for the wheels to contact both rails at the same time. I did this on the problem gap and it worked for a few times then stopped again. At this gap, my main track wires are the same as the loop. In other words, the outside rail is a white wire, the inside is black. It goes like this around the loop until it hits the other gap where the wires conflict like they should. Do I have the loop wired wrong? It's strange because it worked and then stopped with the wires like this. I have the loop wired with 3 feeders separately from the main like the instructions say to.

I added a sketch below.
 

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Discussion Starter · #11 ·
The reason it works at one end and not the other is that one end has the correct and matching phase. The place where it stalls is the gap where there's a conflict.

Digital reversers only correct conflict once during any passage through a reversible section. If there's a conflict at the first gap, there isn't one when it leaves the reversing section. If it's okay at the first gap, it'll be wrong at the far gap. Only once.

As far as I know there are two adjustments to consider. One is to the trip current, while the other is to the time it takes to alter the phase. One, or both, is going to solve your problem. If your engine works around the rest of the rail system, your problem isn't dirty tracks or dirty tires.
What do you mean "Only once"?
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As for my turnouts, I have the proper insulating joiners.
I talked to Digitrax today and the gaps have to deep enough for the wheels to contact both rails at the same time. I did this on the problem gap and it worked for a few times then stopped again. At this gap, my main track wires are the same as the loop. In other words, the outside rail is a white wire, the inside is black. It goes like this around the loop until it hits the other gap where the wires conflict like they should. Do I have the loop wired wrong? It's strange because it worked and then stopped with the wires like this. I have the loop wired with 3 feeders separately from the main like the instructions say to.

I added a sketch below.
The sketch would be more helpful if you showed BOTH rails and what color wire is attached to each one.

All your rails OUTSIDE the reversing loop need to be wired identically, with white to either the right or left rail, and black to the other.

The gap in the rails must be deep enough to sever them. No current can pass through the rails at those points.

Inside the gap, it doesn't matter which color feeder goes to which rail, as long as they all go through the AR1 and they are consistent in their polarity (white and black always to the same rail).
 

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Discussion Starter · #13 ·
Text Drawing Paper Art


Here is an updated sketch showing the loop in question. It comes off the main, around and through a tunnel and back to the main. The wires are the same in the trouble gap but opposite at the good gap. Is this right?
 

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By "Only once," I had intended to reinforce my contention in the first sentence in the post. The AR1 does not make two changes to polarity. It makes one, only one, at whichever end has the conflict. That, in turn, depends on which end the train enters the controlled/switched loop.

Logically, if there is a conflict in phase/polarity when the train enters at the bottom of the loop in the correctly oriented diagramme, it will NOT have to alter the phase/polarity when the train exits a few seconds later at the far gap. That's because the rails across the gap are in phase/polarity there.

Visualize this yourself imagining a train entering at either end of the reversing section, imagine that there's a conflict, or not, and then imagine what must take place (or not) at the other end. You'll see that the AR only has to make a single "correction", not one at both ends.

It is for this reason that the AR must only control what lies between the two gaps, and only that length of 'reversible' track. Meanwhile, out on the greater layout, all wires must be the same on all rails, and they must get power from the DCC system only. So does the AR...it is fed power directly from the DCC outputs. The AR's outputs control ONLY the length of tracks between the gaps, and it matters not which wire/output terminal powers which rail because no matter which way you phase the rails, one end is going to conflict.

Does that all make sense?
 

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If your AR1 output bus is wired to the isolated section
correctly (Red wire to outside rail, black wire to inside
rail, (for example) at both connections), I see no visible reason for your problem.

One thing comes to mind, however. Are you running
a train that is longer than the section between the
insulated joiners? The metal wheels at the end of a long train
could cause a short when the loco wheels reach the
'exit' insulated joiners.

I also continue to be concerned about the use of
Electrofrog turnouts. If there is no insulated joiner
in the frog rails you could experience a short at
your 'troubled gap'.

Don
 

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Discussion Starter · #19 ·
By "Only once," I had intended to reinforce my contention in the first sentence in the post. The AR1 does not make two changes to polarity. It makes one, only one, at whichever end has the conflict. That, in turn, depends on which end the train enters the controlled/switched loop.

Logically, if there is a conflict in phase/polarity when the train enters at the bottom of the loop in the correctly oriented diagramme, it will NOT have to alter the phase/polarity when the train exits a few seconds later at the far gap. That's because the rails across the gap are in phase/polarity there.

Visualize this yourself imagining a train entering at either end of the reversing section, imagine that there's a conflict, or not, and then imagine what must take place (or not) at the other end. You'll see that the AR only has to make a single "correction", not one at both ends.

It is for this reason that the AR must only control what lies between the two gaps, and only that length of 'reversible' track. Meanwhile, out on the greater layout, all wires must be the same on all rails, and they must get power from the DCC system only. So does the AR...it is fed power directly from the DCC outputs. The AR's outputs control ONLY the length of tracks between the gaps, and it matters not which wire/output terminal powers which rail because no matter which way you phase the rails, one end is going to conflict.

Does that all make sense?
It does make sense. I've got it the way it should be, right off the instructions. The diagram confirms it.
I just can't figure out why the engine crossed the "bad gap" a few times back and forth a few times and then stopped at the gap. The rest of the layout runs fine. I got a call into Digitrax so we'll see.
Thank you for your help
 

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Discussion Starter · #20 ·
If your AR1 output bus is wired to the isolated section
correctly (Red wire to outside rail, black wire to inside
rail, (for example) at both connections), I see no visible reason for your problem.

One thing comes to mind, however. Are you running
a train that is longer than the section between the
insulated joiners? The metal wheels at the end of a long train
could cause a short when the loco wheels reach the
'exit' insulated joiners.

I also continue to be concerned about the use of
Electrofrog turnouts. If there is no insulated joiner
in the frog rails you could experience a short at
your 'troubled gap'.

Don
I've wired it according to the directions. I have no train yet, only running one engine.
The electrfrogs have the proper joiners and they are no trouble. I have a call into Digitrax so we'll see.
Thank you for your help.
 
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