Hey guys. I’m having an issue with my auto-reversing section on my N scale layout. (Using the digitrax Zephyr and a digitrax AR-1). I’m a newbie to this hobby so I’m learning a lot everyday! I know this may not be the typical way to use an AR section but I found a similar schematic on the Digitrax website. It seems to make sense but maybe this doesn’t work since the loop doesn’t directly wrap back around on itself. The Problem: Sometimes it works but most of time the engines stall after the first trucks cross the gap into or out of the AR section. The Zephyr display starts scrolling like when there is a short. If I race across the gaps fast enough the engine will stall but then start up again. The fact that it will work sometimes even at slow speeds really has me confused. I have a digitrax AR1 hooked up and all double-gapped were shown. I’m using Peco Electrofrog turnouts with Tortoise switching motors. The turnouts have been made DCC friendly by wiring the frog polarity to change with throw. These are working correctly. I have included a full schematic and a simplified schematic of my layout. The simplified version is a breakdown showing how the basic two main-lines and the AR section are configured without all the over-under levels. (I have not yet built the yard or the helix.) I have played around with the trip current limiting pot with no real success. (When it is all the way to minimum the relay chatters- Is this a clue to a possible short or something I’ve missed?). I read that maybe the AR feeder wires need to be closer to the double gaps so I tried that but this didn’t make any difference. I have also read a blog about a similar problem which turned out to be a faulty AR-1. Hmm.... I would appreciate any suggestions you all can think of! Kindest regards danny mccollim
danny, just in case it has not been said before, Welcome to TB. I am no expert by any means but I will chime in until an expert can make a better assessment of your set up. First, I had a problem deciding if you really have a reverse situation but after looking at the simplified diagram I think you do when coming on or off of the green line turnouts and including only the rails between those turnouts.I think, do not hold me to this, that your feeds for the reverse section are in the wrong place. I believe they need to be inside the gaps and attached to the reverse loop. Don't change anything on my comment but wait for a more knowledgeable person to respond. Oh, BTW if that AR 1 is Digitrax then it could be faulty, just my opinion. Regards, Carl
Thanks for your response Carl! I'm am feeding the reverse loop section from the output of the AR-1 to a couple of locations which I have updated in the new image. Also the electrofrogs are powered from the AR-1 through my Tortoise switch motors. I think i will go back and double check the polarity of the electrofrogs again just to make sure i didn't goof that up.
Danny, Please confirm that the two loops are not sharing track in the left center area. Other than that, the diagram show that you are doing it correctly. I insulate the two inside tracks coming out of the turnouts as I have found that they can cause shorts. If you do that, you will need to drop feeders on to the straights connecting the turnouts that setup for crossover. I am using the PSX-AR but conceptually it is the same.
I don’t have a digitrax Zephyr, but I had a lot of problems with auto-reversers and DCC-short-circuit-protection. I would contact Zephyr and ask them about using the AR-1 with their system. Bob
Hi Paul, thanks for your response! I've been thinking about the common track thing. The two tracks do share a common track in the left center. They are phase coherent and work fine and they are double-gap on both ends. You think that might be the issue? I also do insulate all the inside frog rails coming out of all my turnouts. As it stands now the top green circle (main 2) isn't even in yet. I have not completed installing the track for it. I will give it try with the common track disconnected and see if that does the trick. Thanks again for your input. I'll let you know what happens! danny
Hi Bob. Thanks for responding. The AR1 is from Digitrax as well as the Zephyr and I was told that they are compatible. I'm not using the RailPro AR-1 version> (Maybe I should be!) Thanks Bob danny
Danny, Can you post pictures of your gaps and insulators that border the AR section? I am wondering if the changes you made to the electrofrogs is causing the problem. I did not make my electrofrogs dcc-friendly, I use them straight out of the box.
Hi Danny, When you say you're powering your frogs from your AR-1, do you mean just for the switches *in* the AR section, or also for those switches *leading to* the AR section? If the later, that's not going to work. If you have your frogs wired through your Tortoises, then just use the power feed from whatever bus the switch is on (Main1, Main2, or AR). If you use the AR-1 power feed for one of the switches leading to the AR section (but actually on Main1 or Main2), then as soon as your train enters the AR section the AR-1 is going to switch the frog polarity out from under your Tortoise. If the back of your train is still over the frog, that's going to create a short. Cheers, Jeff.
Thanks for the replay Jeff. I'm only powering the frogs in the AR section from the AR bus so they change polarity with the turnouts within the AR section. The turnouts leading into the AR section are all powered off the main bus. When a loco enters the AR section and there is a polarity miss-match, I hear the relay click but it's not changing the AR track polarity. The engine stalls and because the front truck is in the AR section and the back truck is still in the Main section it shorts the DCC control. If the loco is moving fast enough it will slide through the gap and sometimes briefly stall and then start rolling forward. I'm kinda thinking that the digitrax AR1 might be faulty since won't quickly switch the track polarity even after I hear the relay on the AR1 engage. I have the trip current adjustment set as low as it can go without causing relay chatter. Again, I'm so new to this that maybe I'm mistaken on how AR really works.
Danny, The Digtrax AR is a mechanical relay so it is slower and less reliable than the all electronic ARs (such as the PSX-AR)
It sounds like you've got it all wired correctly (and the clicking relay should be even more evidence of that). I'd be suspecting the AR-1 at this point too.... Can you borrow someone else's AR to give it a try? Cheers, Jeff.
Hey Paul. Here is my poorly drawn pic of the AR section with insulated gaps. The gaps are insulated but the wheels do make contact with both rails between the gaps. The AR section is at the bottom center/right. Can't see the other end of it off to the right side. Thanks for your input! It's much appreciated. danny
Do you run metal wheelsets? If you go into the reversing section and your train is too long it may be crossing both end of it, and cause something similar to what you are doing. I run the PR4 and I have one section that did something close to what you are talking about. And it is always the 1st section and nowhere else. The locomotive consist goes into the section and the reverser goes on and off, I gently pull it back over the double gap and let it re-enter the section and it runs fine and it wont do it again for the operation session. I am pretty sure it must be poor wheel contact that causes a fast change back and forth to shutdown the DCS200. I was told that sometimes it starts in a default and resets the first time something crosses the reverser. Plus I set the settings high enough to handle the load placed on it when it reverses, important if you have sound. and I dont use the fastest setting because it was too sensitive, default is a good start and try one slower so the reverser has a chance to tell the difference between load and a short. On your command station use the default setting for breaker speed. The reverser sounds like it goes off then your command station is seeing the fault too. Try the quarter check at your switches, and particularly at the frogs, I didn't quite understand the frog powered and track power at those locations Jim
Hey, Thanks for your response. Here is what I did to all my Peco electrofrog turnouts to make them DCC friendly.
Do you only have the issue when entering the AR section from Main 2 (via the cross-over), or does it also happen when you enter from Main 1 (the red track)?
From your picture I would say that the green feed should have a insulated gap as well. See the reverser needs to be able to change polarity on both tracks and if you dont have it double gapped it will operate as a fault.
Danny, Do you have a spare length of flex where you can test the AR? I am also concerned that the gaps for the AR detection have insulators, you might remove them and retest.
Hey Paul, I am using insulators between the gaps but they don't come up to the top of the rail head so the wheels do touch and short between the gaps I am using 20 gauge solid core feeder wire off the main bus to wire the whole AR section. Possibly I have a problem with that even though the wires are less than 3 ft long. Maybe I should use the regular 14 gauge bus wire for the whole section?? If that doesn't work, I don't know, I have the whole AR section double gapped like in the drawing below and the AR section is isolated and only gets power from the AR1. If you and the other guys think that the schematic looks like it should work then maybe I should try another AR switcher. Maybe I should get the PSX-AR since it is solid state and it looks more flexible then the digitrax AR1. I should probably get some section breakers and really isolate the blocks on the layout. AR section Full layout draft Simplified breakdown of layout showing main 1,2 and AR section Again, thanks everyone for your input! It is much appreciated!! danny
