Double Dog-bone, DCC & auto reversing

Model Railroader Electronics and DCC
1

Hi all,

First post people but been around this form for quite some time. I found nothing searching this forum for an answer to my question.

The club I belong to has this minor glich.

We have a double dog-bone layout, total layout length is 195-200 feet. We have 2 main lines connected with a loop on each end.

The main lines are separated from both loops so there is essenually 4 parts. Hope this will make sense to you all reading this so far.

We are “HO”, Peco code 83 flex track, Peco Electro frog turnouts, NCE 5 Amp Power House Pro radio, Lenz LZ100 auto reverser in each loop. Loop 1 is East, about 16’ long connected to East main line, Loop 2 is West, about 18’ long connected to West main line. We have this all separated by gaps and circuit breakers.

When we operate non sound locomotives with about 10-20 metal wheel rolling stock, we have no problems with this layout whatsoever.

When we operate sound locomotives with about 10-20 metal wheel rolling stock (Proto 2000, BLI, Intermountain locomotives with sound) we will have the layout shut down when 1 of the locomotives enters or exits one of the loops. Quality locomotives used. No Genesis, Bachman, MRC etc.

Mind you this only starts happening after we have been operating a couple of the trains after about 1/2 hour or so.The trains will operate through the whole layout 4-5 times before 1 of the trains may trip the layout shutdown either entering or exiting a loop.

So, with adjusting the Lenz auto reversers many times we seem to still have the problem and can’t seem to put a finger on what may cause this.

I want to thank you all before hand for reading this and with any answers that you supply that may solve this mystery.

Thanks,

Barry

2

Sounds like the dreaded inrush current issue with the sound decoders. Since it seems to only happen after runnign for a while, perhaps the reversers become heated with continued usage and eventually just stay shut down when the short of crossing the loop gaps rather then turnign the power back on.

–Randy

3

I’m thinking about the frogs on the Peco turnouts. Are these the ones where the two interior rails come together and have a narrow bit of black plastic insulator between them at the center of the frog?

This bit of plastic is just a touch too narrow. When an engine with wheels wider than the gap crosses that section, the wheel momemtarily bridges the gap and causes a short. If your trains are moving fast enough, the wheel will clear the gap before any breaker shuts down, and the problem will have gone away. But, if you’re going slow enough, the engine may stall on the gap.

Randy may be right about the in-rush of current, too. That could explain why this is a problem with sound engines and not with others, or it may be coincidental that your sound engines have wider wheels and are causing the problem for that reason.

Take a bit if fingernail polish and coat the tops of the rails for that tiny quarter-inch area. Once it dries, it should insulate the rails there, making the gap a bit wider and preventing the bridging short.

Another way to look for the problem is to run the trains at night, with all the lights out. You should see a spark on the tracks when the problem is about to happen.

4

Barry,

I have to think your problem is directly related to the extra current that the sound locos draw. I do not use DCC, BUT, a good many of the modelers I associate with do, and I have an electronics/electrical back ground. Every modeler who’s layout DCC system I am faimilar with has has some issue with total load and sound decoders, requiring them to use more power districts or park locos not in use on tracks with kill switches or both.

I have a question for you. What is not “quality” about Genesis, Bachmann, MRC??? I realize Bachmann does not use the highest end decoders in their DCC or DCC sound versions, but I have lots of Spectrum and Genesis, as well as lots of Proto2000. All seem of great quality to me.

It would be a shame to see this hobby degenerate into judging a models quality only on the features of its DCC/sound decoder, as if DCC and sound is the WHOLE hobby.

In my opinion, many early Broadway pieces, diesels especially, where severly lacking in detail, they thought DCC and sound would be the “sell” and detail would not matter. They where wrong, their newer product shows that. And, DCC has far from taken over, look at Broadway now with the Blueline. And, Atlas, Athearn, Proto, all continue to offer both DCC and DC models. Bachmann’s answer is to offer less expenive decoder equiped locos that are easily removed or upgraded to suit the needs/wants of the user.

Sheldon

5

No, does not. To me a dog-bone would have no reversing loops. A double-dog bone would have 4 tracks running through the middle part and once again not require any reversing loops. Do mean it is a loop-to-loop that has two loops at each end, one for each main line? Or do you mean it is a dog-bone that has double crossovers at each end so either main line can be used as a loop-to-loop?

Without understanding the layout this may or may not make sense. When this happens is the train always following the exact same path or is this just when a crossover between the mains is used?

Do the Lenz autoreverse units reset back to a rest state, when the train has left the block? Are all the auto-reversers set up exactly the same (I hate to say same polarity but that is what I mean)? That is, does an eastbound train on the main always stay status-quo entering the loop right-hand and always trip the auto-reverse if it enters the loop from the left-hand?

6

When the thread is about DCC then quality one is talking about is going to be the DCC component. If we had to cover all the quality of every aspect of every thing we talked about we would be spending hours and hours with disclaimers and exceptions and getting nothing discussed. Yeeeesh! It is bad enough that the lawyers do that in product instruction manuals. This lawn mower is not to be used for picking one’s teeth.

7

All my DCC friends use Digitrax and their inferior Bachmann and Genesis locos run just fine with the decoders that came in them.

8

Thanks to all responses so far.

I have added the track plan and hope you can all understand about the double loop.

I will need to try the fingernail polish technique when I get to the club next time and report on that.

I liked the answer about too much current draw of the locomotives as I failed to mention that they are in consist of 2-3 locomotives.

I was not trying to make reference to any quality of each company but wanted it known what locomotives were used as I was presuming somebody would ask. Not to question other company locomotives. It just happened to be that at the club only one member has locomotives stored there and we used his. He only buys those brands. I own Spectrum, Genesis etc. at home with an NCE the same as the club and I have no problems with them. I have run my Spectrum 4-8-2 sound at the club and it still does it.

The reverse units will always reset after we move the locomotive back from the gap and release the locomotive. This always happens at the gap. The gaps are on each end of each loop.

The East line is separate from the West line. The East line has 1 loop and the West line has another loop. Each loop has its own revers unit. We have several crossovers and they have all gaps. We do not have any shorts just reverse units shutting down the 2 main lines.

Hope this will help.

Barry

9

Ok, I’ve looked at the track plan and unless there is more track that is not shown on the diagram, I do not understand why either of the loops need reversing wiring. ??? The only “reversing” situation that I see is in the lower yard between near where it says UTP #6 and UTP #7. In this case, I would put the reversing unit in the yard (with gaps where the 2 to 3 centered crossover is) rather than on the loop. There would have to be another set of gaps on the track that leaves via crossover toward the industries at the top of the diagram and the top yard.

I’ve put red in where I think the track should be isolated and auto reversing applied.

640×480 37.6 KB

The green line is one I am wondering if is there but not showing on the original diagram.

10

Barry,

Are there any crossovers along the main line that are not shown on the drawing? If not, as others have said, no reverser is needed or desirable on the main line.

As to the quality thing, thank you for explaining. I think a better distiction might have been to discribe the higher end units as just that, high end, advanced features, etc. The word Quality implies good or bad construction, not the features of a product. Toyota, Ford or Honda (the three car makers with the highest quality ratings) would all tell you their least expensive car is built with just as much quality as their most.

It sounds even more like the reversers you are using cannot handle the current your consists are drawing.

Sheldon

11

Sheldon, Texas Zephyr & others,

I have attached a simplified plan to show exactly what we have with our problem.

I forget to mention about the crossovers, we have 7.

I had the original post ready and mentioned crossovers and lost it trying to get it posted and when I made the new post forgot to mention the crossovers. My bad.

Sheldon, sorry about the quality issue you are right and I stand corrected in my choice of words.

I am of the opinion that maybe the reverse units are the problem and will maybe need to contact Lenz about this.

Thanks,

Barry

12

Barry

You have a single long dogbone here with no reversing loops. Both ends are just the ends of the bone.

You do have 6 reversing sections where your crossovers connect both sides of the long single loop however.

The Lenz reversing unit’s will be sensing a short and make a clicking sound as they try to correct it whenever a loco is crossing over and causing a short on those crossovers even though they are not protecting it correctly.

13

Hi all,

Getting closer to getting this solved.[:)]

The folded dog-bone (Not double dog-bone, wrote that wrong) has 7 crossovers and all insulated between the crossovers. When we crossover we never have shorting, tripping out problems. All trains go through the crossovers each way and never have missed a beat. We also use the crossovers to get trains out of the way of another train coming as it serves as passing-meeting sidings too.

Received a note from Lenz on the sensitivity level of the auto reverse units and were misunderstanding the best way to set them. We have readjusted them to their suggested specs.

I mentioned also that we have all seven sections of our layout with circuit breakers. When we set them up we used 4 amps thinking we didn’t want to have too much amperage going through the layout to cause problems with shorts if they would occur, well that is incorrect and need to have them set to 5 amps also.

Well, yesterday we ran 2-3 powered loco consist with sound, both with 16-40’ boxcars and a Bachmann Spectrum with sound and 7 passenger cars for about 2 hours or so and we didn’t trip the reverse units so maybe with a little luck we may have most of the problem solved.

I want to THANK YOU ALL that responded and offered answers to this problem. This was a great experience and glad that I could be part of this forum and get GREAT answers from you all.

Hopefully this may be solved, will be operating trains today.

Barry

14

[quote user=“ATLANTIC CENTRAL”]

Barry,

I have to think your problem is directly related to the extra current that the sound locos draw. I do not use DCC, BUT, a good many of the modelers I associate with do, and I have an electronics/electrical back ground. Every modeler who’s layout DCC system I am faimilar with has has some issue with total load and sound decoders, requiring them to use more power districts or park locos not in use on tracks with kill switches or both.

Sound decoders only draw .01 amps of extra power. That isnt the issue. The issue is the Cap storing a small charge and the amount of current required on startup to charge it. Our layout has 30-40 locos running at once with no issues (and most have sound).

I have a question for you. What is not “quality” about Genesis, Bachmann, MRC??? I realize Bachmann does not use the highest end decoders in their DCC or DCC sound versions, but I have lots of Spectrum and Genesis, as well as lots of Proto2000. All seem of great quality to me.

Bachmann uses the Soundtraxx Tsunami for their sound…it is high end. But their spectrum line of locos are hit and miss. No, proto is not top end quality, infact, they have many well-documented issues. And what MRC products are you refering to?

It would be a shame to see this hobby degenerate into judging a models quality only on the features of its DCC/sound decoder, as if DCC and sound is the WHOLE hobby.

Degenerate? Thw Whole hobby? Where was that said? How about an emerging new aspect to the hobby? Wouldnt that be a better way of saying things? My hobby is all-encompasing. I bash, detail, paint and install all of my locomotives. My hobby has many facets, not just DCC/Sound.

In my opinion, many early Broadway pieces, diesels especially, where severly lacking in detail, they thought DCC and sound would be the “sell” and