Adding Command Control to a “Typical” Layout

Now that you’ve seen all the steps, let’s take a moment to look at the bigger picture. What do you need to convert a layout to command control? Of course, no two layouts are the same and even if they were, the people who build and run them aren’t. So there is no single formula or “Right / Wrong” way to do this. But to give you some perspective, we’ve created a sample layout to convert.

We’ve tried to include just about anything we could think of that you might want to have on yours, and we’ll adapt all of its features to command control. You may not need / want to do all of these, or you may have ground to cover, but this “typical” layout should give you some valuable perspective.

basic trackplan

Our sample track plan combines many typical layout elements.

The size of this railroad isn’t really an issue. it could be 8 x 16 or 80 x 116 (wouldn’t that be nice!) The main features remain the same. Note that these diagrams are not shown to scale should you want to recreate this layout exactly. Let’s start with the track plan itself.

Our layout features three continuous running loops, each connected by crossovers. Two of the loops feature extra passing sidings. In the center, we have a small yard and an engine service area.

With this plan, you could run three trains continuously while shuffling power around the engine house. You could also set the crossovers to go from loop-to-loop and create a longer single run.



Dividing the railroad into separate power districts makes it easier to understand and control.

First, let’s divide up this railroad into more manageable chunks and get our power supply needs straight.

We’re going to break this plan into four separate power districts; one for each loop, and a fourth for the yard and engine area. It makes sense to give this section its own district for three reasons:

  1. Even in conventional modes, you may want independent control here for your switching while other trains run continuously.
  2. With all the extra locomotives and possibly lighted or animated cars, there will be sufficient power draw here to warrant the extra supply.
  3. By giving this section its own circuit and breaker, a derailment here won’t stop trains on the mainlines.

In all locations where you see the colors change, ie. in between loops, you will need to have an insulated center rail. This will separate the power districts in either command or conventional control.

So, what do you need for power? To start, you will want either a TMCC-1 or a LEGACY command control system. (You only need one.)


PowerHouse 180 Watt power supply

If you want to run only command control engines, you’ll also need:

  1. Four TMCC Direct Lockons (6-34120) – one for each track district for circuit protection.
  2. Four PowerHouse 180 Watt power supplies (6-22983) – one for each track district providing 10 Amps of power to each.

If you want to run both command and conventional trains then you may want to consider:

  1. Four TMCC Direct Lockons (6-34120) – one for each track district for circuit protection.
  2. Four PowerHouse transformers.
  3. Either Four Powermasters (6-24130) – one for each track district. This would work best for a layout using mostly modern DC motors with low current draw.
  4. OR combinations of four TPC300 (6-14189) and/or TPC400s (6-14179) – one for each track district. This will provide all the power you could ever want for older Pulmore motors, passenger trains with lots of lighted cars, etc.

Remember that by wiring all of these loops with the same common ground and keeping your transformers in phase, your trains will not see any difference when traveling from loop to loop.


At a minimum, you’ll want gaps at these locations to isolate areas you may want to park a locomotive or train.

The passing sidings and spurs may be further separated by using insulated inside rail sections and BPC controllers (6-14184) or ASC controllers (6-14182) to turn the power to these sections on and off independently from the track loop to which they are attached. See the diagram for gap locations and blocks. For these 9 blocks you’ll need either 3 BPCs or 2 ASCs.

Both of these options will give you some room for expansion so you could isolate additional sections as well (such as the mainline by the passing sidings.) This will allow you to turn off power to a sitting train and reduce overall current draw and prevent errant movements like starting running a locomotive into the turntable pit or another train.


Assuming all of the switches on this layout are remote control, and you want to control them all with your command control system, what do you need? The specific controllers you use will depend on the types of switches and switch motors you’ve chosen for your layout. You can use either the ASC (6-14182) or the SC-2 (6-22980). To determine which is best for you, review this guide.


With a crossover, you’ll never want to throw just one switch, so both can be wired to the same address.

We can greatly reduce the number of controllers needed by assigning multiple switches to the same addresses. Not only is this more economical, it will help prevent derailments and other problems as well since you’ll never want to throw one without the other. A good example of this are crossovers between the loops. The same can be applied to the passing sidings, although you don’t have to.


The switches, as controlled, are shown here.

Note that the crossover at the top of the plan between the inner and outermost loops actually crosses the center loop on a diamond. Both of these switches are on the same control as well.

Looking at the total plan, although we have 25 switches, we can reduce the number of “controlled” switches to just 16. These could be controlled with three SC-2 (with two addresses to spare) or four ASC controllers.

As you can see, a little advanced planning can save a lot of headaches and money! Of course should your railroad continue to grow, you can still add more controllers.


With accessories, the number of options is nearly infinite. Keep in mind that some accessories can be controlled by outside insulated rails or 153 series switches and these won’t require any conversion to command control at all.

For additional accessories like lighted buildings, an animated switch tower or other accessories, you’ll want to use the ASC or SC-2. Simply divide the number of activations required by 8 for the ASC or by 6 or 12 for the SC-2 depending on your requirements to determine how many you’ll need. For your uncoupling tracks and operating tracks, the OTC will work. You’ll need one for every 4 uncoupling tracks or 2 operating tracks on the railroad.

Last but not least, we have a turntable. This can be controlled using an AMC (6-14183), an ASC or by equipping it with a receiver as we’ve shown here.

For all of your accessories, a 14 Volt constant power supply is best. You can use just about any power supply for this, from older post-war transformers to the CW-80 from your set, to the AVC (6-14186). Just wire your accessories to a common ground and keep your transformers in phase for best operations and easiest wiring.

There you have it! An entire action-filled train platform converted to command control. To review how we put together all of this, just review this video: [youtube=] And you’ll find detailed instructions on all of these parts and installations throughout these pages.

0 thoughts on “Adding Command Control to a “Typical” Layout

  1. I have a sixty five year old loco and most cars are 55-65 years old. I want to layout a continuous loop with switches etc. but I need some guidance as to how to prepare my cars, the track. Currently the engine cannot pull that many cars with only one transformer…but I have multiple transformers and need some help in how to lay them out to pull more cars or add another contemporary engine

  2. I have a layout similar to to your “typical layout” (no turntable and only 13 command switches). All I own now is the new ZW-L transformer and a new Legacy Command CAB-2 Remote. Can/will the ZW-L power the entire layout/switches? If so, I presume I will need to utilize block sections? If so, can all the switches be run off of 1 ZW-L. I will only run Legacy locomotives.

    • The ZW-L should be able to handle all of your power needs. If you have a lot of lighted buildings and other accessories, it would not hurt to place these on an independent power supply. (Any transformer that can provide the recommended 14 Volts will do.)

  3. Sorry to ask this question here but I cannot figure out how to post a question otherwise….
    Who makes/sells the “rollers” that you use in your product videos to test locomotives on a track…..Bill

  4. I’m building something close to your sample layout using Ross Custom manual switches and track. I will have roundhouse and turntable. Two track main line and need to shuffle loco’s in and out. I’m really confused on how to wire all of this specifically the part of taking a loco from one power section to the other to get to the roundhouse and back. Any suggestions on how I can get help through correspondence, books etc.?

    • Woody,

      Blocking the tracks does allow you to turn sections off or control multiple conventional trains on the same network by shutting down sections or distributing them to separate power sources. As long as each section is powered (and with conventional control powered at the same voltage) the locomotive won’t even see the change from one section to the next. If you have other specific questions, check out the various pages on the blog here. Some of the small details like wire hook-up locations may vary but the basic principles will work with all brands of track. You can use Lionel control systems like LEGACY and switch controllers with Ross Custom switches and track too without any problems.

      If you run into more problems or questions that we haven’t already covered, feel free to drop a line here anytime.

      • Thank you for responding. I’m still confused and probably over thinking this. I will be conventional (postwar power). Lets look at the diagram. If the red main line is powered by a transformer and the cross over to the blue line is gaped and the blue line also powered by a transformer so the two trains can go different speeds when operating independently on each line how do you go from one main line to the other when using different power supplies? I get using one power supply and gaps but that would mean when running the trains on each main they would be restricted to going the same speed. I’m I making any sense? or out in left field?

        • No problem. You have two options. First, you could simply set each transformer to the same voltage. As the train crosses from one line to the other it won’t know the difference.

          A more elaborate solution is to wire each of the track loops and blocks to toggle or rotary switches which connect them not just to one transformer but all of them. These switches would then not just turn a track block on or off but route the power to it from one of any number of transformers.

          If you are using only two transformers, a DPDT center-off toggle switch will work. You’ll need one switch for each block. Connect the bottom pair of leads on the back of each switch to the two wires from transformer 1, the center pair to the bus / feeder wires for the track block and the top pair to the wires from transformer 2.

          Flip the switch up and your train gets power from T-1. Down, you’re getting power from T-2. In the center the track will be off. For 3 or more power supplies, you’ll want a rotary switch with more positions but the practice is the same.

          It’s harder to describe than to wire. You can practice on a simple loop of track to start. Try wiring a stretch of track as described above using just one track, toggle switch and two power supplies. Once you’ve done one, all you have to do is wire more switches in the line, connecting the respective transformer lines to each other and wiring the center posts to each new block of track you add.

  5. I will have three separate loops can I run a single common bus providing outside rail power to all three loops while I use individual wires for each center rail or do I need a separate common feed for each loop. My conventional layout uses one #10 common bus for everything on the layout, accessories as well as trains.

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