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Help With Wiring Diagram For DC/DCC Operation On My Layout

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  • Member since
    August 2023
  • 3 posts
Help With Wiring Diagram For DC/DCC Operation On My Layout
Posted by Lucas B on Saturday, August 5, 2023 10:24 PM

Hi, I am very new to wiring a layout from scratch and I have done some research on what to do with having both DC and a DCC system together, but I feel that what I have is too complicated to piece together from posts and videos online.

So I'm posting here 2 images of a rough wiring diagram of my layout and I want to see if what I have is good and would work fine.

To give context to what I want out of the track plan is for there to be 2 main lines, which are powered seprately from eachother but still have crossover tracks to connect the 2 line (they are isolated from eachother), then I got a storage yard in green which is only for rolling stock and at most have one maybe two engines on it. The last thing I want to mention is the Top layer of the layout which is DC Only powered and there will be a block to transition any DCC engines before going on or off the main line. 

My Layout, Bottom Layer

My Layout, Top Layer

Tags: Wiring
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Posted by wrench567 on Monday, August 7, 2023 11:02 AM

  In my opinion, it's not worth running the risk of blowing up a DCC system just to run a couple of DC locomotives. Wire the layout for DC block control and when your fleet is ready switch over to DCC. Easier that way than the alternative of a dual system. You can still run your DCC locomotives on DC until every one has a decoder. Your layout will be already to accept the DCC system.

        Pete.

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    November 2013
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Posted by snjroy on Monday, August 7, 2023 11:13 AM

Welcome to the forum!  

I tend to agree with Pete, to prevent blowouts, the best approach is to have the system either DC or DCC. The last thing you want is to see a DCC loco cross over to the DC section by mystake, or a DC loco go to the DCC section. You risk blowing up a decoder or your DCC station, depending on the incident.

What you can do is use a single DPDT switch that allows you to power your entire layout in DC or DCC. You still need to make sure that your decoders are programmed to work in DC mode. You can  break up your layout in blocks to facilitate DC running. They will work fine in DCC mode.

Simon

 

 

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Posted by crossthedog on Monday, August 7, 2023 11:15 AM

wrench567
Wire the layout for DC block control and when your fleet is ready switch over to DCC.

I don't see that the OP has suggested he wants to start with DC and then move to DCC. Maybe I missed it, but it looks to me like the question is about running both. I do that, and I haven't blown up my DCC system or any locomotives. Separate the systems with a DPDT switch and only have one system plugged in at a time (the DC power packs or the DCC throttle power), and before you throw the switch make sure you know which locomotives are on the track. Works for me. 

-Matt 

Returning to model railroading after 40 years and taking unconscionable liberties with the SP&S, Northern Pacific and Great Northern roads in the '40s and '50s.

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Posted by gregc on Monday, August 7, 2023 11:24 AM

at this point, i think it would be clearer to deal with just the DC wiring.   looks like you tried to illustrate the connections to various switches selecting DC or DCC, but i don't understand some.   for each "block", a DPDT switch can select DC/DCC.   additional switches can select specific throttles for a DC controlled block

there are several reversing sections that need specific attention (i see no notes identifying them)

it's not clear how many DC throttles you expect to be able to route to various blocks.  i'm not sure that i see only 1 (maybe a 2nd separate throttle near the roundhouse)

not sure if you just want to be able to control one DC/DCC train thru the layout  or multiple trains at the same time.    if you just want to be able to control one DC or DCC train, you won't need many blocks and a single DPDT switch could be used to select DC or DCC, as mentioned.  on the other hand, if you want to run more than one train and one is DC, the mainline needs to be blocked, as well as multiple switching/yard areas.   standard toggle switches would allow 2 DC trains.

switching and yard areas could also be isolated from the rest of the layout and a DPDT switch likewise used to select DC/DCC.    some tracks could be powered thru a SPST switch allowing a DC or DCC engine to be parked in a DC area

not sure i'm addressing all the issues or your specific concerns.   ask questions or provide more input

greg - Philadelphia & Reading / Reading

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Posted by jjdamnit on Monday, August 7, 2023 2:02 PM

Hello All,

Welcome to the forums.

Your first few posts will be moderated so there will be a delay in seeing them.

Mixing active DC & DCC on the same layout is a BAD idea!

Lucas B
...what I want out of the track plan is for there to be 2 main lines, which are powered seprately (SIC) from eachother (SIC) but still have crossover tracks to connect the 2 line...

Your explanation of wanting to combine the two incompatible systems is to run two (2) engine(s) or trains simultaneously- -if I'm reading that correctly.

The reason for using DCC is the ability to run several locomotives simultaneously.

With DCC, the continuously running train is set to a speed and allowed to run on its own.

Then the DCC controller "grabs" another engine or train and controls it, while the continuously running train goes merrily along. 

Digitrax throttles have the ability to control the speed of two (2) different engines or trains via their dual throttle knobs.

Electronically speaking, Direct Current is varied by the rheostat in the controller (power pack- -AKA cab) 0-12v.

A rheostat is much like a faucet for electricity. Depending on how "open" the rheostat is the more power flows through it to the device it is powering; in this case the DC motor in the locomotive.

DCC is a combination of constant AC; typically 14 volts, supplied by the booster (power source) and Digital Control Packets; generated by the throttle and then "combined" with the AC at the command station and both are sent down the rails. (An extremely simplified explanation.)

These Control Packets are programmed with a specific address. Only the decoder(s) with this address respond to these commands.

DC and DCC systems are completely incompatible and when accidentally combined catastrophic things happen to the electronic components- -that's BAD- -and can be dangerous (fire) and expensive (blown components)!

Caveat: Many DCC decoders can run off of DC- -"Dual Mode"- -and need to be set for this operation. Some DCC systems can "mimic" a DC signal to run a DC engine (known as "Zeo Bit Stretching) but is not recommended for prolonged running.

I am by no means saying that what you want to do is not possible.

However, the potential risks outweigh the minimal rewards.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

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Posted by Lucas B on Monday, August 7, 2023 3:41 PM

Okay so to update, not long after I made the post, I did find out about the problems of using DC and DCC at the same time. But for me, I can't change all my engines to DCC as some of them are pretty old and I don't trust myself just yet to make some of them DCC equipped, and anyway about 90% of my engines are DC only while the other 10% are DCC equipped and I have ALOT of engines.

  • Member since
    August 2023
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Posted by Lucas B on Monday, August 7, 2023 4:08 PM

The reversing sections I haven't thought of because I didnt really know what to do with them and how to wire them, I mainly thought of the blocks sections and where to isolate them and also what block sections should have a switch to turn on/off the power going to that block section. I also have some isolated frogs that have to be powered but that too I didn't do anything on there with.

Now about the throttles I was going to having a main DC 4 throttle that can power 4 separate outputs and to have a small DC throttle used for Coal Mine, Harbour and the Roundhouse/Engine Storage for each one.

I do want to run more than one engine at a time but I have a 2 track mainline to have 1 running on 1st track and the other on the 2nd but I do have switches that crossover to the other line would be isolated with plactic railjoiners. With the yards they would either be empty with no engines or there would be 1 engine there and they too would be isolated from the other sections.

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Posted by jjdamnit on Monday, August 7, 2023 5:30 PM

Hello All,

Lucas B
...I am very new to wiring a layout from scratch...but I feel that what I have is too complicated to piece together from posts and videos online.

After viewing your track plans they seem quite ambitious; no matter the control system!

Lucas B
The reversing sections I haven't thought of because I didnt really know what to do with them and how to wire them...

Reversing sections need to be identified, isolated and can be controlled manually or automatically in both DC and DCC.

Manual control of reversing sections (in both DC and DCC) require isolating the entire reverse section and manually throwing a toggle switch when the locomotive(s) or entire train clears the entrance to the reversing section.

This can be automated in DC by the addition of relays; triggered by the remote turnout motor and additional wiring- -more money and complexity.

With DCC, automating this process is done by adding an Auto Reversing unit or having a separate booster; with AR capabilities built in (more expense).

Before converting to DCC my HO 4'x8' pike had 16 blocks controlled by two (2) cabs (controllers). Some blocks were as small as a single section of 9-inch track.

Running just two (2) locomotives simultaneously was like "playing the piano with boxing gloves on."

Switching to DCC- -and automating the reversing section- -allowed me to operate several locomotives and consists more easily and efficiently.

The amount of money I spent on wire alone to power those 16 blocks could have paid for an entry DCC system, let alone the controllers and block switching units.

DC is often presumed to be a "cheaper" option to DCC, but in my experience, this seems to be the opposite.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

  • Member since
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Posted by wrench567 on Monday, August 7, 2023 7:19 PM

Lucas B

Okay so to update, not long after I made the post, I did find out about the problems of using DC and DCC at the same time. But for me, I can't change all my engines to DCC as some of them are pretty old and I don't trust myself just yet to make some of them DCC equipped, and anyway about 90% of my engines are DC only while the other 10% are DCC equipped and I have ALOT of engines.

 

    The reason for my first post. Wire the layout for DC and work out the inevitable bugs on DC. Reversing sections can be handled by DTDP switches or relays. A good portion of us have had to change the length of reversing sections. Everything always looks good on paper then reality sets in and you find one leg of the whye is too short or too long. It's also easy to build yourself a reversing section in a reversing section. Don't ask me how I know. I thought a simple cross over to a track in an already established reversing section would be alright. How wrong I was. Drove me crazy for awhile.

    Wire for DC and work out the inevitable kinks. Then after all your locomotives are ready, it's a simple move to DCC if you still want to. I'm a huge advocate for DCC but know quite a few die hard DC guys that have extensive layouts with wireless DC throttles and many cabs on rotary switches. They have op sessions with multiple operators and one layout had 8 cabs. He's recently switched to Digitrax DCC.

     Pete.

 

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Posted by MisterBeasley on Tuesday, August 8, 2023 4:09 PM

Welcome

I had a lot of trains in boxes from my teenage years.  I originally planned to build a DC layout because that's all I had and I was familiar with it.  I figured I would eventually convert to DCC when I was ready.  I figured my 5x12 foot layout would be pretty much runable and presentable in 8 or 9 months.  By this time I was in my 50s, so the trains I had were old.

I did a lot of research, even suffering from "analysis paralysis" for a while, but eventually I started reviving my carpentry skills, experimented with new-fangled foam layout construction and laid down a loop of track.

I hooked up my ancient power pack to my new loop of shiny nickel silver track.  To my dismay, my old engines barely ran, although my electrical work checked out fine.   This is, unfortunately,  a common problem with ancient models.  I got a bit of money from somewhere and bought a DCC system, a working new train and a decoder for that.  Within a day or two, I had a new subway train, something I'd always wanted, my first hand-held throttle and I was in business.  I made a decision.  I disconnected the DC system and put it away, eventually using it to power a turntable and some of those new-fangled LED things.  I never went back.

I slowly acquired a few freight engines, and began the long process of replacing old horn-hook couplers.  At first, I only bought cheap motor-only decoders.  I researched fixing up my old engines with new motors, new trucks, new wheels and new drive trains, and discovered I could get brand new locomotives for less.

Fast forward and I never actually upgraded an old engine and got it running.  I just trashed a few crummy locomotives,  and i gutted and converted a few others to dummies.  The 8 or 9 months to get that first phase of my layout running took five years.  While I was doing it, I was never happier.  I have replaced the couplers and wheelsets on 95% of my old rolling stock and refurbished a few trackside structures. 

Best laid plans.  They're a good starting point, but don't be afraid to change them when something better comes along.

It takes an iron man to play with a toy iron horse. 

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