Digitrax users seem to not run into termination issues. I am not sure if their layouts have smaller bus runs, or the Digitrax boosters are better at filtering the output signal.
NCE user discussions seem to talk about termination and the use of 'snubbers' quite often. If you are getting a lot of 'ringing' like in the MR article, then adding snubbers(no matter what system you are using) is a good idea. Of course, you really need a good oscilloscope(and know how to use it) to see if you are getting large spikes and noise on the DCC signal.
And Lion, the DCC bus is where the termination 'snubber' needs to be placed. Usually the cab bus has termination in the cab plug-in panels.
Jim - Feeling much better about our club system right now.
Modeling BNSF and Milwaukee Road in SW Wisconsin
I also use wire nuts for the ends.
Ken G Price My N-Scale Layout
Digitrax Super Empire Builder Radio System. South Valley Texas Railroad. SVTRR
N-Scale out west. 1996-1998 or so! UP, SP, Missouri Pacific, C&NW.
I've never had a problem making a loop out of my rail bus. As noted, the track is a continuous loop in an oval. Now on layouts large enough that a continuous loop might actually cause timing problems, they will most likely be large enough layouts that there will be more then one power district. Since you would not connect power districts together, no loop is possible.
Digitrax definitely says to not loop loconet. Just don't.
Martin Myers
Tom,
I can't speak to other systems, but Digitrax instructs you not to do that. I'm not sure why because the track is a continuous loop, but that is what their instructions say.
Dave
Lackawanna Route of the Phoebe Snow
Some one please correct me if Im wrong but, but aren't we suppose to not terminate the buss ?
I was told I should strip the two buss wires and solder them back onto the buss creating a continuous loop , I haven't encountered any problems running it this way but if it is the wrong way I'd like to make it right.
Maybe i have been ill advised , if so can somebody suggest the correct way of doing this?
Tom from Down Under
Termination of the Track Bus is different from the termination of the DCC Bus, assuming you are using something akin to the Loco Net. Some require termination as did the old coaxial computer networks. Networks with switches and hubs do not require this, ergo, it is built into the system. If you can plug many nodes into one netwark like an extention telephone it may (or may not) work differently. With my parents telephones, these two can be on the line with each other, but that one must be on by itself.
This isssue will be pecular to your own network, so those of us here may be less than helpful. LION does not use DCC, him just keeps blowing things up until him find something that works.
ROAR
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
You might not need this. Termination. 100 ohm resistor in series with a 0.l ufd ceramic capacitor at the end
Tech info in the link. Have fun. It does start opinions, discussions.
https://sites.google.com/site/markgurries/home/dcc-general-best-practices/wiring-planing/snubbers-rc-filter
He has lots of good DCC info. Take your time.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
MisterBeasleyuse a consistent wiring color code. I use red wire for the "outside" rail and black wire for the "inside" rail, both bus and feeders.
Yes, that's the way mine is set-up, too. Works great, generally.
The only catch is sometimes you have a line that twists back on itself so that you end up with red on the inside and black on the outside. So keep that in mind if suddenly this convention stops working. You'll think it's something else at first, but it will eventually be the fact that the rule can get you in trouble if you're not careful about this one thing.
Mike Lehman
Urbana, IL
oltmanndThat's a great looking bit of wiring, Dave!
Sure, Sure, and all of those terminal strips and connectors cost lots and lots of money. LION is CHEAP, and NAILS IS CHEAPER!
MisterBeasley Phoebe Vet Thank you. If I can add one thing it is LABEL EVERYTHING. Worth repeating, so I'll do that. Also, use a consistent wiring color code. I use red wire for the "outside" rail and black wire for the "inside" rail, both bus and feeders. It greatly simplifies things when you're crawling around beneath the layout wondering which feeder goes to which bus wire.
Phoebe Vet Thank you. If I can add one thing it is LABEL EVERYTHING.
Thank you. If I can add one thing it is LABEL EVERYTHING.
Worth repeating, so I'll do that. Also, use a consistent wiring color code. I use red wire for the "outside" rail and black wire for the "inside" rail, both bus and feeders. It greatly simplifies things when you're crawling around beneath the layout wondering which feeder goes to which bus wire.
Mable, Mable, where *is* my label?
Color coding. Sheesh you guys *are* picky. LION takes whatever wire him can get for free and does not worry about color.
GROUND BUS is uninsulated. That way I know it is the ground bus.
(no, wait... I have lots of uninsulated beeses.)
OK, GROUND is on TOP (exept in places where it is not.)
This is getting complicated.
Next is the SIGNAL and DETECTOR bus, a line running +16v dc. LION use reed switches for detectors, and put magnets under train. Works well, it also picks up any stray nails, staples, rails and any other ferrous object. Also causes shorts and derailments untill all trash is removed from the ROW.
Next is HOTEL POWER, a +12v dc circuit used for lighting all over the place. LIONS have lots of LED lights along the layout.
FINALLY is 600V DC power to the third rail. Ok it is really 10.2v dc. Since the LEFT rail is grounded, +10.2v DC moves the train forward and - 10.2 v DC moves the train in reverse. No, wait! This is a subway layout, trains do not go in reverse. Ok, at least THAT makes the wiring more simple, yes?
Yes all of these wires are bare, and so yes they do have labels every six feet or so. LION made bare wires at the suggestion of powerhouse boss, clamp 14ga solid wire in a vice, and use a carpet knife to strip the insulation off. Works fairly quickly, but a problem there is. Apparently this process leaves a residue that does not like solder. LION must wash area with Lacquer Thinner, dry area, attach wire, apply flux, apply heat, and then apply solder. Sheesh!
For devices, turnouts, signals, relays, and detector returns, LION uses whatever wire him can get, but if you must go and buy some, look for 25 pair cat 3 thelephone cable. You cannot go wrong with that. Of course before buing that LION used up all of his 66 conductor organ console cables. These are OLD cables, and have no plastic or rubber insulation on them. They are all wrapped with wax and string. And they are all white, but at least they separated into six 11 conductor strands and so I would connect wire at the distribution point and then use a tester until I got the right conductor to connect at the distal pont. There are about 300 such conductors on the route of the Broadway LION, and so you can see why the LION wants to cut down on the numbers of conductors him installs. Since these conductors connect at patch panels at both ends, it is only necessary to log the pin number that the conductor is connected to to know what the wire is used for.
If wiring diagram for LION it is that you want to see, check out his Operations Manual.
It takes an iron man to play with a toy iron horse.
Phoebe Vet My bus to feeder connections are made at barrier strips. The bus therefor ends at a barrier strip. The IDC issue has many strong opinions on both sides. Put me on the against IDCs side of the isue. I like my swing down boards with barrier strips because they make troubleshooting and modifications simple and possible without crawling under the layout.
My bus to feeder connections are made at barrier strips. The bus therefor ends at a barrier strip.
The IDC issue has many strong opinions on both sides. Put me on the against IDCs side of the isue. I like my swing down boards with barrier strips because they make troubleshooting and modifications simple and possible without crawling under the layout.
That's a great looking bit of wiring, Dave!
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
mlehmanI just tied mine in a knot so they wouldn't slip back through the last holes in the benchwork...
I always thought that knot was so the lectricity wouldn't leak out the end.
My last set of feeders are soldered to the ends of the bus and coated in liquid electrical tape.
Brent
"All of the world's problems are the result of the difference between how we think and how the world works."
I just put a wire nut on the end of each (prevent a possible short to something like the other wire).
Alternately, transition each as you suggest (e.g., via an IDC) to the final, smaller feeder wire. The latter approach would be like a household 120v AC circuit, going to various outlets on it's route, then tied to the last one as a termination, avoiding loose ends. This illustrates what, of course, not to do; i.e., tie the two ends together and create a short.
Paul
Modeling HO with a transition era UP bent
I just tied mine in a knot so they wouldn't slip back through the last holes in the benchwork...
Actually, nothing works just fine except in rare cases. I'd just leave them alone for now and perhaps study the issues a bit. It was all the rage ast one time, until it just didn't matter for a lot of folks.
Now the IDC vs soldering debate will get people going. I favor wire nuts myself, but I tend to be a bit of a bottom feeder when it comes to electricity.
This is my first foray into running multiple feeders to the track, I have always been able to just run two wires to the track with no feeders until this new, larger layout. Maybe I am over-thinking this, but how and where do I terminate my bus? At the last (i.e. furthest away from my command station) set of feeders? I am going to try using IDC's for all my connections, so is this ok or should I solder that last connection? I am using Kato Unitrack with terminal rail joiners, so those will just run straight down under the table to the bus.