DCC or DC control on my layout

[Mutro]

On 5/3/2024 at 3:18 PM, brill27mcb said:

It looks to me like your layout is actually well-suited for DC operation with two power packs, except for one thing. That is that one track of your pair almost acts like an oval, while the parallel track almost does an up-and-over figure-8. If you made all trains cross over at the double-crossover, you would have two separate loops operationally. But if you run the trains straight through the crossover, which you probably do, what you have operationally is a single big long loop. Then a train that starts running left-to-right at the top of your track plan later finds itself running back right-to-left there in the opposite direction on the parallel track. It's an interesting plan, but it creates logic issues like the ones you are running into. One solution would be to remove the crossover (not the double crossover, the crossover under the bridge) to create two separate loops (one all blue and one all orange). Then, when you want to switch a train from one of these loops to the other loop, set the power pack speeds and directions to match while you cross the train over on the double-crossover.

 

@brill27mcb   Thanks  for your input.  Due to conflicts with the logic of the layout as you note, operating with two powepacks, I was running into short-circuit issues and, and at times with two power packs powering the same locomotive. So now I am currently running all parts of the layout under just one powerpack. (see diagram 1) 

But I'm still trying to find a solution of using two powerpacks to run two rains separately somehow.  After much trial and error,  I believe that in order to keep my internal switching operations on powerpack #1 (yellow)  and the other powerpack #2 (blue) for through lines, I believe I need to keep the crossover (under the bridge) and use my double-crossover (in the crossover setting) to switch between two separate operating lines (See diagram 2). 

However, unfortunately the continuous through-tracks of the double-crossover (the outer tracks) I think are creating shorts.  I'm not familiar enough with how the individual components within the double-crossover are powered/not-powered, but I did try isolators at one end of the double-crossover unit but that creates a power dead-spot within the double-crossover. One possibility I thought of is to cut and isolate the two continuous outer rails of the double-crossover unit, and power the ends with differing powerpacks in the cross-over scheme, but that may not solve the issue.

 

As I am stymied with this situation at the moment, so suggestions greatly appreciated!

[Junech]

Just a small thought about the double-crossover:

 

You could fully isolate the red part and let it be either the blue or yellow powerpack.

 

For automated switching between the two powerpacks something similar to automated railroad crossings (detect train -> do something) could work. But instead of handling the railroad crossing it needs to switch between the powerpacks, probably with some kind of relay circuit.

 

[MeTheSwede]

 

 

 

 

It all looks quite complicated, but unless I'm misstaken it all boils down to the diagram below, with a bunch of insignificant sidings attached to the orange part.

 

 

 

If so the question becomes how to hook up the double crossover correctly. Bear in mind, that usually straight ahead in the crossover means there are two loops, whereas here the double across setting will produce two loops.

 

I neither use Kato nor couble crossovers, so I will leave that question to someone else.

 

Edited June 27 by MeTheSwede

[Kamome]

Ultimately the double crossover is fully isolated from one side to another whether you take the straight or diverging track. There is a plastic track piece through the middle so you could run it like this.

 

The issues I see are its a very nice elaborate design, but really only allows the running of a single train at a time. Unless the plan is to leave one train running, and then control another to ensure no collisions. As you switch from one power pack to the other, you may get surging across the double crossover, especially if there is another train in that power district. 

 

I may also suggest testing the incline and inner loops with piers by the roundhouse to make sure they don't snag pantographs. On paper these should fit but many of the piers have a slight overhang.

 

I like the design though, plenty of play value. Would be a great layout for some signalling and occupancy detectors on DCC automation.

[chadbag]

I'm biased.  I'm a nerd.  DCC is always the answer.

 

[Cat]

Big advantage of DCC on any layout is the ability to run trains smoothly at very low speeds because the track is always at full power.

[dotzen]

My two cents worth, just because I'm such a fanboy...

If you can manage to plug a few electronic components together you can build a DCC command station and booster for very little cost.

This is DCC-EX, it's a fully functional DCC system with the added bonus of also allowing control of DC locos.

If you want to get into automation with detectors, signals, etc it's all possible, you can have one train running to a script and have manual control over another. The scripted train will obey signals and work just like the real thing.

I know it's not for everyone, but it's full of features not available on commercial systems, and the only cost is the hardware.

 

d.

[cteno4]

Ok I’ll pipe in on the other side. I don’t mean or want to start a war, but I think there are good points to good old DC.
 

I’m a nerd too and tech head personally and professionally and can do and enjoy all the wiring, programming, etc needed for dcc, but I find it’s just not worth the time and expense investment for me. Simple throttle control has kept me happy. I’ve played with dcc on friends’ layouts and it’s fun, but I don’t find I need it much to enjoy the hobby. I have a few hundred trains and converting them would be an enormous task. I have many projects I want to do and limited time so dcc just goes onto the pile of not worth it for me. 

 

Using the nonpolar cleaners also has been reducing track power issues a lot to where trains run slow well now also.

 

Yes DC is limited in some of the things you can’t do with it, but I find few of those things I really want/need to be happy with dcc, especially when I weigh in the costs involved.

 

We each have our own needs, wants, skills, interests, resources, etc related to the hobby that are the key in determining if DC or DCC is the best solution for each of us. The answer for one of us may not be the answer for another one of us.

 

jeff

[dotzen]

You've hit the key point for sticking with DC, the cost and effort to fit decoders all your locos.

I have no intention of trying to fit decoders to any of my Kato locos. It can be done, but they were never designed for them and it's fiddly, something I can do without.

I use DCC-EX for my other locos that were designed for DCC and most of them have decoders fitted.

I was playing around with basic automation for my Kato stuff, encouraged by the Automation thread on this site, but this was around the same time the DCC-EX guys started work on Ex-Rail automation. They then took the extra step of making the control station work in DC mode.

This then allowed the Ex-Rail automation to be used with DC locos. If your layout is built around block control you can operate multiple locos on the layout.

It's PWM, not pure DC, but I personally think it is better. I converted all my Kato controllers to PWM years ago.

You can use your phone as a wifi throttle, its pretty neat.

Like I said, it's not for everyone, the automation rabbit hole can be pretty deep, but you don't have to use all the bells and whistles.

A simple PWM DC controller with a wifi throttle for not may dollars may be attractive to some people.

 

d.

[Mutro]

Thanks for all your insight, suggestions.

 

But back to the beginning of this thread... My thought initially was that I need to convert my DC system to DCC to do all the operational things I wanted to do on my layout,  with 8 locos and 3 passenger sets (and growing).  But when I looked into the feasibility, time and expense of converting the locos and passenger sets (4 are SL's and definitely not DCC friendly, others are indeterminate. When I asked a KATO staff at their Tokyo HQ, he admitted only the 485 and a couple of Kitaguni carriages had provisions for drop-in decoders, and converting the rest of my units would be "very challenging"). Then there're switches, turntable, command station, yada-yada... I became overwhelmed, stuck in neutral.  So I gave up and reduced the two powerpack system to a dumb one power pack layout, just running one train at a time. But not a happy camper...

 

But then thanks to suggestions from @brill27mcb, @Junech and @MeTheSwede I tried a segmented DC approach with isolators and additional power feeds.  This system has it's limitations as @Kamome notes, but hey, it works (no more shorts and powerpack conflicts) and does most of what I wanted to do... without the pain of going to DCC. 

 

A happy camper with my small DC layout, I've put my DCC aspirations on hold, for now.  I think DCC is great, genius really. But the cost - benefit of DCC for me doesn't pan out, for now...

 

Here's my revised layout.  This allows two trains operating independently.

 

Edited June 29 by Mutro

[Mutro]

23 hours ago, Kamome said:

I may also suggest testing the incline and inner loops with piers by the roundhouse to make sure they don't snag pantographs. On paper these should fit but many of the piers have a slight overhang.

 

I installed spacers between the parallel tracks so they don't interfere with each other.

 

23 hours ago, Kamome said:

but really only allows the running of a single train at a time. Unless the plan is to leave one train running, and then control another to ensure no collisions. As you switch from one power pack to the other, you may get surging across the double crossover, especially if there is another train in that power district. 

 

I'm actually able to run two trains at a time. Either with one running at a constant speed, or have a second person to control the second powerpack. And yes, the double-crossover and the crossover are issues to avoid collisions. 

 

 

 

 

 

 

[brill27mcb]

Yes, what was not clear to me in the initial discussion was that you wanted all of the switching and sidings to be on the yellow loop.

 

Rich K.