Questions re: Track wiring in a Garden Layout : LUSENET : Wiring for DCC : One Thread

I'm planning on building a garden railroad this year. While I'll be starting out with a simple loop, I want to plan for future upgrades I hope to add which will involve several turnouts, reverse sections, etc. For this reason, I want to start using DCC from the beginning.

I live in the Fort Worth/Dallas area; so, I'll have to contend with similar weather/soil conditions as Allen does. I will be using Aristocraft Code 332 brass rail. I'm planning on soldering jumper wires across joints and/or using rail clamps (e.g. SplitJaw). My thought is to solder jumpers across several pieces of track into a section, and then use rail clamps to connect the sections together. I also plan on using rail clamps for turnouts, bridges, etc. (to allow easy removal for maintenance).

I've been reading the section "DCC in the Garden) on Allen Gartner's web site (; however, there are a few points I'm not clear on.

1) Type of wire for feeders Allen recommends #12 solid wire for feeders. He also points out problems using underground sprinkler wire, low voltage lighting wire, etc. Does this mean I should just use uninsulated wire (just good ol solid copper grounding wire)? How does this work when the ground is wet? How far apart should I strive to keep the two feeder wires (for each rail) from each other (to minimize shorting through the ground)?

2)How are the feeder wires connected to the track? Are they Soldered? Or should I use some sort of clamp?

3) Do the feeder wires all route back to the booster? Or is there a single connection from booster to track and the feeder wires just run under the track - connecting to the track every 12' or so.

4) How should isolated blocks (such as a reversing section) be wired? I plan on initially using some sort of reversing circuit (e.g. Digitrax PM4 or similar). It won't be practical to place the reversing circuit near the isolated track section (where it would be exposed to the weather); so, should I plan on locating the reversing circuit near the booster and running a separate set of feeder wires to each isolated track section?

5) Ultimately, I would also like to have block detection and computer control so that I can be entertaining guests while several trains are running simultaneously with the computer making sure they don't run into each other. Does this mean I need a separate feeder wire for each block? Would the block feeder wires all need to feed back to a central (weatherproof) location where the block detection circuits are located? Or should I have a separate set of block detection feeder wires (perhaps using underground sprinkler wire) which feeds back to the block detection circuits (which are located in a weatherproof location near the booster)?

As you can probably tell, I'm new to all of this; so, I apologize if some of my questions are trivial.


-- Jon Davis (, February 13, 2002


Hi Jon.

1. I would use insulated wire. Then You don't have to worry about spacing. 2. I don't think it is that important which way You go, as long as You end up with a good connection. If soldering is not Your strenth, use clamps. 3. You run a two bus wires from Your main unit or booster along the track and connect feeder wires from the bus wire to the track. 4. What ever works best in Your situation. If You can build something weather proof, close to the reversing loop, that would save You a lot of wiring work. 5. If You are serious about this point You should really consider Zimo and STP. It is the most advanced and complete system on the market, ready to hook up to a PC. And You can use an old 386 for that. With this system You don't need any seperate block detection wires. The blocks need only be done on one rail and the power wire for the block comes from the block control unit rather than the booster. You can check the system out here:

Have fun, Art

-- Art Luescher (, February 15, 2002.

You may be able to dispense with a feeder bus all together. Code 332 brass rail has more cross section that a 10 Ga wire although brass is not as conductive as the wire might be. I run 80' sections on one feeder (two 18 Ga pairs per section). Further, in each case, the feeders are at one end of each section. Before I set my layout up for cab control which was way before I installed DCC, I ran the whole 300' loop on ONE feeder and I didn't detect much voltage to the far part of the loop.

-- George Schreyer (, February 15, 2002.


It was tempting to jump right in on this one. The people who help answer questions on this forum do a great job. I like people like yourself to get the benefit of a variety of opinions. Now that you have a few, which have indeed been good, here is a little more info for you.

Since you are in the DFW area, join the NTGRC. Be sure to join immediately as I will hosting the club shortly. A link to the NTGRC is found under the link for the area train shows. Also check out the link for my Finchfield and Wrensylvania if you have not already done so.

I would use insulated wire, too. But all will find this interesting. Two years ago before a show we had an ice storm (pictures on my page. ) I thought for sure the ice would conduct well enough to trip the boosters. It's the impurities in water that really makes it conduct. Evidently, the ice was pure enough that it did not trip the boosters. However, in dirt (impurities!), moisture will likely rob your boosters of power, if not trip them, if you used bare buried wire.

In the DFW with our infamous moving clay soil, I have learned that using sectional track, as you are planning on doing, is the way to go. Flex 250, is too prototypical to fight the forces of nature and pops out of the ties. 322 has oversized spikes that more firmly grip the rail. Flex is beautiful, but I'm paying a maintenance price.

Also, due to our soil, you MUST use a concrete, rebar reinforced subroadbed. Use portland cement mixed with chicken grit for ballast that doesn't settle and collect leaves under the ties. How I wish I had done all this to start with!

I, too, have my garden wired for block detection. But I gave up before every implementing computer control of multiple trains on the same track for two reasons. One, since I didn't start with concrete, my trackwork is no longer perfect. Also, concrete or not, I suspect our Texas heat is also working to create gaps in my track that I have to periodically fix. If multiple trains are to be on the same track under computer control, you will need flawless operation - unless you like the sound of expensive trains slamming into each other.

Two, after visiting a convention, where many people had automatic control of their trains, I noticed that most of them spent the time during the show trying to get the stuff to work and stay working. Poor electrical contact by the trains would falsely trip their systems into the next state and mess up their show. In theory, a well written program can provide a certain degree of immunity to this problem. Discussing this is a big topic in itself.

The Zimo, as someone else suggested, does look like a good choice. While my primary equipment is Digitrax, the Zimo decoders are my favorite because they offer back EMF speed control - very useful on my very rugged garden railway. My only real critique of the Zimo decoders is that they do not offer many lighting features American modelers want. Should you choose Zimo, you can get it from the Train Connection, listed on my list of manufacturers link.

All my electronics is in the garage. This means lots of wires run to the garage. But the wire cost is cheaper than trying to waterproof electronics. You only need run one electrical feeder per block back to your dry area.

-- Allan Gartner (, February 16, 2002.

Zimo's MX66 decoder does have special American lighting effects like Mars, Strobe, Ditch, Gyra (CVs # 125 - 128); available since September 2001.

... and with our dollar being in the basement we might have a bargain for You!


-- Art Luescher (, February 16, 2002.


Thanks for pointing out that Zimo took my advice! Funny thing is that I just got their data sheet on the MX66 a few days ago. All it says is "lighting effects." - which I assumed was what it had before.

Their web page does indicate the effects you mentioned; which should make a lot of people happy.

I didn't see flickering firebox, but most G-scale steam locos today come with that in some way or can be added when a sound system such as the Soundtraxx Sierra is used which has it built in. Note that the sound systems that implement this and have the flicker synchronized with the shoveling of coal is really the way to go for this effect.

-- Allan Gartner (, February 17, 2002.

I really appreciate everyone's comments. I look forward to the day when I've got sufficient experience and expertise so that I can help others as a way of giving back to the hobby.

Some of the responses have generated more questions. Also, a few comments.

re: Insulated wire for feeder busses. What type of insulated wire is suitable for underground burial (in Texas soil)? I had been planning on using 12ga low voltage lighting wire; but, Allen's page on "DCC in the garden" points out that solder joints and soil stresses can break down the individual wire strands over time. Allen also points out that cutting into the jacket of buriable "romex" nullifies the jacket's benefit. What solid wire has an insulated jacket suitable for burial and underground connections?

re: concrete, rebar reinforced subroadbed. How wide and deep (under the track) would the concrete subroadbed need to be to counteract the Texas forces of nature? Does it really need to be rebar reinforced, or would wire mesh reinforcement (such as what they put under patio's) be sufficient. It seems rebar would be very difficult to bend around curves. Also, would the track sit directly on the concrete subroadbed, and ballest used to fill in between the ties and hide the subroadbed? Or would there still need to be some layer of ballest between the top of the subroadbed and the bottom of the track ties?

re: Use portland cement mixed with chicken grit for ballast. Using portland cement seems like it would lock the track in the ballast and restrict movement. What about expansion? Would this mixture allow sufficient movement of the track in the ballest for expansion? Or am I just making this more complicated than it really is? Also, I happen to have a pile of decomposed granite sitting in my backyard. I needed it for another project I was working on last year (building a path) and had some extra delivered in anticipation of using it on my garden railroad. Can I assume this will work instead of chicken grit? It has lots of sharp edges and packs very tight.

re: The North Texas Garden Railway Consortium (NTGRC). I would love to join the NTGRC. I periodically check their meeting schedule to see when I could attend. Unfortunantly their meetings are always on Sunday which which prevents me from attending. I have tried talking to NTGRC folks at the Plano Train Show; but, there is just too many people and too much going on to have meaningful conversations. If the NTGRC meetings were (occasionally) on Saturday's, or even weekday evenings then I might be able to adjust my schedule to attend. Until then, I'll have to rely on information I get from the internet and dealers.

re: Which DCC system to use I haven't decided yet which DCC system to use; however, I am leaning heavily towards Digitrax, at least for their command station, loconet, and wireless (radio) throttles. For decoders, I'm leaning heavily towards Zimo and/or NCE. One thing I like about Digitrax is the amount of information that is available. There is even a Yahoo Group dedicated to DCC computer control via loconet (i.e. loconet_hackers). The Zimo system looks impressive (and is, perhaps, more industrial grade quaility); however, I just haven't found the scope of information on it as I have on Digitrax (at least in English). Also, it is quite expensive. For the price of a Zimo system, I could purchase a Digitrax Super Chief II AND another train.

re: Computer control I work in the software development industry as an I/T Architect. This might explain my fasination with the possibilities of DCC computer control. But I also understand the inherient problems with having multiple systems interoperating in a less than optimal network. What I'm actually hoping to achieve is more what I consider Computer-Assisted control; that is, having a computer sit in the background monitoring what is happening on the layout and either taking corrective action (such as switching a turnout to route a train to a different siding), stopping trains that occupy adjacent blocks, or even shutting down the whole system so that a human operator could step in and correct the situation. I'm hoping to do all of this with a PalmPilot; so, when I'm outside playing with my trains, I can just pop my Palm in and start an application to watch what is happening on the layout. That way, if my attention is diverted, the worst that might happen is that everything shuts down.

Again, I really appreciate the time people take to put up web sites and answer stupid quesions like mine. Last year, I concentrated on doing some preparatory yard work (paths, retaining walls, etc.) and purchasing track. This year, I still have some preparatory work to finish up (such as building a tunnel); but, I plan to start laying the track. Ultimately, I may never achieve the level of computer-assisted control that I dream of, but I would at least like to have it wired correctly so that I could do it.


-- Jon Davis (, February 17, 2002.


I forgot to mention the obvious (to me). I use standard insulated wire. Much of this wire has a jacket that is oil and gas resistant. I don't know that is necessary, but it certainly won't hurt. The obvious I forgot to mention is to cover joints with liquid electrical tape of liquid vinyl to make an attempt at resealing the joints.

I buried #10 wires for buses, more so that maybe they won't break, maybe, when I hit it with a shovel than anything. I use #12 for the feeders to the track.

The concrete issue is off-topic for this forum, but I wanted to make sure you knew about it. As long as I am answering electrical questions as above, okay, but otherwise, we'll take this off-line.

I tried using hardware cloth, but making it into small piecees, especially for curves, was a major pain. I also wasn't confident it would withstand cracking from the forces of our Texas soil.

Rebar comes in 1,2, and 4' lengths (and longer), that makes it convenient.

How deep? I'm not a concrete expert, but I'm told rebar should not be so close to the surface that water can get to it. 4" deep is not a big deal. You will find of all the ways to make subroadbed, concrete is actually the cheapest! Screw all the complex methods you may have read about. Dig a hole, fill it, level it, let it dry. Make it about 8" wide so weeds don't grow up through the middle of your tracks and stay off your right of way. Measure the width of your trains. 8" wide isn't too wide. Plants and weeds will grow onto your ROW in about 2 weeks anyway. If I were to do it all over again, I would have built the railroad on cinderblocks and then back-filled with dirt. When I got close to the track height, then poured the concrete.

-- Allan Gartner (, February 17, 2002.


It is exactly because of things like command stations, loconet or radio throttle You should look closer in to Zimo. One Zimo command station supplies 8Amps of power. You can also get a station with a built in booster at 16Amps. And of course You can keep adding. It also allows You to select a voltage output between 12.0 and 24.0V, has a built in Volt and Amp meter for each output, generates stabilized and short-circuit protected track supply and data signal according to DCC and/or MOTOROLA protocol, allows shuttle train operation for two trains independent of any computer. By means of configuration variables the user is able to modify things like DCC timing (in order to solve certain decoder problems), output current limits (in order to prevent damage of vehicles), RS232 bit rate, stop time for shuttle trains, etc. Easy software update for new features like new configuration variables, connecting new modules or extensions of the data protocol according to new NMRA recommendations by means of loading the FLASH-EPROM from computer (internet or disk) or by exchange of the FLASH EPROM. For a loconet, Zimo uses a true CAN bus. The ZIMO CAN-Bus is probably the most powerful and reliable data link used in model railroad control today. It works as a Local Area Network (LAN) with multi-master capability - there is no time-consuming polling by a central device.

HIGHEST SPEED (115 kbit/s):

This is more than any of the rival systems offer. Although a bus with lower speed would be sufficient if used as cab bus only, the ZIMO CAN-Bus shows its superior performance if e.g. hundreds of occupancy detectors and loco number identification boards have to transmit continually changing information to a computer (or to some computers). Because of this high performance the ZIMO system needs not to use separated cab and feedback buses, but all data transmission is done within one network. The CAN-Bus hardware and software protocol is widely used in industrial, automotive and medical applications. The physical layer is similar to the well-known RS-485 standard, but with special capabilities in order to handle heavy traffic efficiently. Extensive automatic error recognition and correction are included in the CAN protocol. Error counters, which are provided in the microcontrollers of all cabs and modules, allow successful problem diagnosis, if this should be necessary at some time. Radio throttles: Zimo just released a radio throttle. As with the infrared throttle which is available for decades it uses bidirectional comunication for highest reliability. It can also be used in thetered mode which charges the batteries at the same time. Regarding computer control, You would be hard prest to find anything better then the Zimo/STP combination. It is perfect for what You have in mind. The software allows You to run Your trains manually, semy-automatic or fully automatic. You will "see " the trains operating on the computer switch board. It will also show You which train (number) sits on which track. I hope that gives You some more information You were looking for. If You need more info please contact me at: Zimo also has an english website with lots of information:

What ever system You choose, have fun with it!


-- Art Luescher (, February 18, 2002.

Speaking of gardens, visit:


-- imme (¿¿¿??, January 21, 2003.

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