DCC Wiring

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Ceresco2063

New Member
New to DCC, my expierience was with anolog and the Arnold block system in the early 80's.

I have the outer twin track loops layed and blocked. Now a few questions.

In the crossovers do the two circuits need to be isolated, the inner loop, isolated from the outer loop. Isolating the passing rail at stations and along routes seems easy, but it appears the KATO crossover or 8 turnout option appears to be a differant issue.
If I run analog equipment on spurs and I open that circuit to bring a main line unit in to pick up units on the spurs how do I switch select them from analog to DCC then back to analog, without carry over voltage.

My sound like simple questions to some, but not an electrical engineer, and want no issues with the volumn of track and yards planned. Right now I still have the two freight yards unpowered, and the main station loading lanes unpowered. I am using 4 #4 turnouts on crossovers and isolating each loop but appears when I switch to take unit from outer to inner loop there is a 'spike' as unit accelerates then resumes after it clears turnout crossover section. Looking at the KATO 20-210 crossover, to replace the #4 crossover currently in use, but need to know of any electrical issues.
 
I am not certain what the Arnold block system is, but it certainly sounds to me like the layout basically has separate dedicated power supplies to different parts of the layout. Yes, running a train over the gap between two power supplies can definitely give it 2x the power it needs.

I highly do not recommend running a normal power supply simultaneously with DCC. Eventually a train is going to stall on the transition and fry the train, one of the power supplies, or all three.

I would suggest going to a full cab control block system for the analaog trains. Then if you want to run DCC just make the DCC system one of the cabs. Flip all the cab selector switches to that cab and the layout will then be a DCC layout.
 
It is strongly discouraged by knowledgeable electronics practitioners to mix DC and DCC on the same layout. Further, even though the two may be wisely segregated, if they co-exist on a layout, the locomotive bridging the two types of current may bring the DCC system to grief. Expensive grief. Unless you have a substantial gap between them, a gapped length of rails longer than the longest power-picking item of rolling stock (including a locomotive), you can expect some expensive repairs to the DCC system.
 


FWIW, I'm now contemplating going DCC, after 40 years in the hobby or so. Why am I going DCC? I've been assimilated? No.
I'm currently building a new layout, which I expect to be 'the layout of a lifetime,' for me. I've been collecting stuff, and toying with the concept since coming up with it, in about 1981. I've also bought other 'off concept stuff,' for one reason or another, over this time, as I too, and be convinced to buy 'that new shiny thing, I saw, or heard about, last week/month/etc,' just like any other undisciplined window shopper, the LHS owner loves to have come into his/her store, and/or our hobby/country needs to maintain some semblence of 'health,' as traditionally defined. I haven't gone DCC to date for several reasons, I won't go into here given the late hour I'm writing this right now. Bottom line, more or less was 'I have over 200 locomotives-making the switch is/would be cost prohibitive, now/going forward.'

Since starting to design and build the new layout, I'm again faced with the choices regarding 'control.' If I stay DC, how will I 'wire the layout,' for multiple train operations, etc. Or, put another way, how simple can I make the wiring, so that I'll actually be able to run this layout, within my lifetime, + do scenery, & have a non-model railroading life? I'm not as young as I used to be, don't have the time like I used to, yet still want to be 'self reliant,' when it comes down to maintaining and enjoying the layout, myself. I've decided to go DCC, as not all of my current inventory of locomotives, do I plan on operating on the new layout. Additionally, DCC, does have the option to use 'one' locomotive without a decoder, so its not exactly true that 'every locomotive has to have a decoder' to be compatible with DCC. If I rotate which locomotive I use as the 'decoderless one,' there's no need to put a decoder in every locomotive.

It seems to me, that people want their cake and eat it too, when it comes down to making the choice between DC vs DCC controls. DCC systems all come with the 'can operate one decoderless loco' ability, thanks to the NMRA, as I see it, yet people aren't mature enough to realize 'there's always some trade offs involved with making a decision,' in 'the real world.'

Going forward, I plan on reducing my assortment of locomotives, as even with a warehouse sized layout, I don't think its possible for a single person to have the ability to individually control 200 locomotives, or even say 50-100 consists simultaneously, unless 'you're Superman modeling the UP in Wyoming, or PRR NEC in their heydays...' Having the ability to expand your layout, or motive power fleet is one thing. Requiring a system that can accomodate every possible combination of layout wiring, make and model of locomotive and decoders, etc., is very expensive, and never going to be utilized, or built to such a great extent as possible, by MOST currently armchair modelers. Its one thing to own 10 locomotives and a 5'x 10' HO layout, its completely something else to be able to own, build and run a warehouse sized layout, built, run, and maintained by an individual modeler. And when it comes to a group, or club situation, there is a totally different dynamic involved, than with say, a single modeler, with a modest space, limited budget, and only so much time for the hobby.

Guess what I'm trying to say in a nutshell is: Can some 'administrator,' 'bookmark' at least one indepth thread about 'what type of DCC/DC system should I use to control the trains on my layout?' Perhaps every year or so, an update could be posted, to keep the info current, given what is new, old, and available...It would be a service to every forum member, past, present and future. I'll stop my rant now.
Regards,
Otiscnj
 
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Additionally, DCC, does have the option to use 'one' locomotive without a decoder, ...

DCC systems all come with the 'can operate one decoderless loco' ability, thanks to the NMRA...


Otiscnj

Actually, only two systems have that capability. Bachmann's EZCommand,(don't know about the Dynamis), and Digitrax. Plus coupled with the fact that leaving a DC locomotive on a DCC track without running it, can lead to seriously damaging the motor, its more of a gimmick than a serious alternative to another decoder. I wouldn't count on it.
 
After much reading and research yesterday decesion is made. The outer loops and accociated yards and passing lines will be DCC. A totally isolated inner loop and spider lines will be just DC. From what I have read, and your comments gentleman, it appears totally seperate and isolated DC layouts within the total layout is the way to go.

The Arnold 'Block' system marketed by Arnold was a control system of actual 2.5cmX2.5cm plastic 'blocks' you assembled in a control grid, where the electrical system in the 'blocks' maintained the spacing of the trains automatically along the actual track 'blocks', as long as the associated block wiring and train sensors worked as intended. It was pretty advanced for the era, but alas Arnold itself folded in 1995, and now aquired by Hornby out of GB and the Arnold line was seriously cut back to Loco's and rolling stock. Can't even get additional cantenary mast sets anymore, one of the reasons I was forced to go US rather than German in the new layout. (and the costs of DCC N-Guage German equipment)

Still a work in progress, we have a train show in Council Bluff, IA this weekend, and one in Lincoln, NE the next, and the finance Czar (da momma) has authorized a substantial budget. Her goal is to model our Nebraska farm on the layout, and she is a great help in all this.
 
I too would recommend against having DCC and DC in adjoining blocks. Best to wire it so the whole railroad is DC or DCC and cannot be a mix. As some may forget DCC can control one DC only loco.
 
While I don't have 200 locomotives, I do have somewhere between 50-80 (lost count after starting my latest layout). I, too, am getting up there (70-1/2), but put together a layout in a 14 x 14 dedicated room. Except for about 4 diesels and a Climax, which are recent acquistions, and are DCC/Sound equipped, all my motive power is DC. I have neither the time (run my own business +) nor money to convert everything to DCC. Plus, I am pretty much a single operator, having some difficulty walking and chewing gum simultaneously. My layout is set up in blocks, but has but a single main line, with two yards. I use MRC's Tech 6 6.0 which is dual-mode capable, but not simultaneously (i.e., you have to have it switched to either DCC or DC). Because I nearly fried a DC loco by inadvertantly leaving the Tech 6 in DCC mode, I decided to install a medium-sized DPDT toggle on my control panel. One side is connected to the Tech 6; the other side is connected to a MRC Tech 4 260, which is a DC power pack. All turnouts are run off a separate AC power pack I picked up at my LHS. The Tech 6 is left in DCC mode. It is very easy to see which mode is selected by the position of the toggle on the panel, so no accidents have occurred (so far :o ). Each block is connected to a DPDT Center OFF mini-toggle. (Only one side of the toggle are connected, so they are essentially simple ON-OFF switches, but by using double-pole toggles each block is completely isolated from the other...i.e., NO common rail wiring. A DC loco can be parked in one block, and the bigger "mode" toggle on the control panel flipped to DCC, or visa versa.

If you are going to operate each loop completely independently of the other (no crossovers between them), the the simplest way is to wire each loop to a separate power pack, one DCC and the other DC, with NO connection between the two. OTOH, if you are going to run a train from one loop to the other, with the other type of locomotive, then my strong suggestion would be to separate the entire system into blocks, and have an arrangement like mine, with the DC locomotives being isolated in a particular block. You could wire the block DPDT toggles to select between DC and DCC, but run the risk of getting confused and shorting across two blocks of opposite type power systems. I have been tempted to do just that, but the space inside my control panels is very tight now with wiring, and I really can't see trying to solder the wires to the other side of each mini-toggle!
 
Carey,

I tend to agree, and have the same concerns regarding the 'one decoderless locomotive,' on a DCC layout. Agree, its more of a gimick, than anything.

My feeling is it doesn't pay to be 'on the fence.' No matter which way you go, its probably going to involve some compromises-thats life...accept it, and move on....

Otis
 
I have a Digitrax Zephyr Xtra and I have run DC locos on it before I converted them to DCC. After seeing what is capable with DCC I doubt that you would be content to run a DC loco with a DCC controller. Plus, you'll have that annoying buss coming from the DC loco...........and it IS annoying. Also makes you wonder when the meltdown will begin!:eek: otiscnj is right on this..........DCC is nothing to be on the fence about.
 


I've been collecting stuff, and toying with the concept since coming up with it, in about 1981.
What a coincidence. DCC was becoming a concept right around 1981. The original CTC-16 designs were published in 1979.

Bottom line, more or less was 'I have over 200 locomotives-making the switch is/would be cost prohibitive, now/going forward.'
Don't let that stop you. I've got hundreds of locomotives that are yet to be converted. Some of which I had before and some I've purchased after. I would never run them all anyway so why do I need to convert them. I convert them as I need to use them.
Some will probably never be converted because the mechanical aspects of them have become obsolete anyway.

Additionally, DCC, does have the option to use 'one' locomotive without a decoder, so its not exactly true that 'every locomotive has to have a decoder' to be compatible with DCC.
It is true that SOME of the manufacturers have this option (channel 0); however, I highly recommend that it not be used. As long as the locomotive is actually running there is not problem. It is when the locomotive stops and just sits on the track. It gets constant high frequency (basically flat wave AC) power through the motor. The motor will eventually burn out. Remember AC is used to de-magnetize things. Jeff Wimberly did some tests and found that old Athearn Blue Box motors can be ruined in as few as 8 hours. (correct me if I'm wrong here Jeff). I ran one G-scale locomotive as DC on the DCC Christmas layout. The next year when I set up the Christmas layout the motor was so weak I had to replace it.


DCC systems all come with the 'can operate one decoderless loco' ability, thanks to the NMRA,
no they don't. Check the manual carefully of the systems you are considering purchasing to make certain they have this feature.

Its one thing to own 10 locomotives and a 5'x 10' HO layout, its completely something else to be able to own, build and run a warehouse sized layout, built, run, and maintained by an individual modeler.
I would say that is a most true statement. I had plans for a warehouse sized layout. Then I started hanging around the Greeley Freight Station Museum. Even after 5 years of construction by a team of 10s of people, it still takes 10s of people to maintain it. I decided I am not even going to attempt such a thing on my own.

Guess what I'm trying to say in a nutshell is: Can some 'administrator,' 'bookmark' at least one indepth thread about 'what type of DCC/DC system should I use to control the trains on my layout?'
That is perhaps the most common asked question over on the electronics thread. The problem is that there is no "best" answer or even correct answer. If there was everyone would buy that system and it would defeat the purpose of having a vendor to vendor standard. The "right" system for your layout could be different if it was a different person operating it.

I have a CVP Easy DCC, an NCE-Pro-R, a Lenz Set-100, and a Digitrax Zephyr. I can recommend them all. Ultimately it depends which one you like, which throttles you like, and possibly some of the features you want (like the channel 0 DC operation thing).
 




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