I’ve got all my track down (HO), I’ll be going DCC, and I’m at the wiring stage. I’ve read up on DCC and I have a good understanding and shouldn’t have any real problems with wiring. I have about 150 ft. total track length including the mainline, yards and a switching yard. I hooked up a DC power pack from a starter set, and, at least for now, I have power to every piece of track using one connection point. This was confirmed by running a DC loco all over the layout. I know that there was definitely a voltage drop by using one feed for the entire layout so I understand the reason for using multiple feeds. All the track is connected with track joiners, probably 1/3 to 1/2 half of which are also soldered.
My questions primarily concern the feeders for DCC. Just about everything I’ve read states that feeders should be used every 3-6 ft. I also recall that someone spaced them at 9’ or 10’ without problems. I’ve never really found an explanation why the distances are what they are. Is it because of issues with degradation of the DCC signal to the loco? Is it because DCC locos are more sensitive to voltage loss or fluctuations? Does it have to do with the booster being able to properly detect a short (the quarter test)? Or a combination of any of them? Or are there other reasons?
I plan on using, at most, 3 locos at once, with no more than two together (as a lead and helper) and the third as a separate switcher. I also plan on using the Tam Valley DCC capable servo controllers for turnout control. These are connected to the DCC bus. Does using two locos together, drawing more current, and creating a greater voltage drop, necessitate the use of shorter feeder distances? Or is that irrelevant?
Based on what I’ve read, I plan on using a 6 ft. distance. Has anyone here used a 9’-10’ distance without problems? Anybody used a separation even greater than that?
I know that this has been a long post with many questions, but I’ve done many searches using various
It’s not really signal degredation, it’s reliable power distribution.
Some will scoff at my methods, saying rail joiners are never good connections, but it’s worked well on two layouts now, even after painting the rail - and I make sure to get plenty around the joiners because a shiny spot peekign out is most unrealistic.
My method: I use flex track, so before forming a curve I solder two pieces together. Using rail joienrs. I solder feeder wires to those joiners. These are the only track joints I solder. At every OTHER track joint, I have feeders soldered to every pair of rail joiners. For a pair of turnouts laid point to point, that’s5 sets of feeders in that short distance - possibly overkill, but I NEVER have problems with flickering headlights and sound dropouts. I just make them up ahead of time - I keep a drawer full of pairs of rail joiners with feeder wires soldered on. Do not buy the premade ones, they cost WAY too much. When I get ot the end of a piece of track and go to conenct the next one, I add a pair of my feeder joiners and proceed. The end result is I have power feed at a maximum of 3 feet between points, most of the time it’s actually less. But since the feeder wires are made up ahead of time, comfortably at the bench and not bent over the layotu trying to solder a wire to the rail, it’s really easier. I use only fresh joiners, not ones that have been used over and over again and are loose on the rails.
Here is the rule of thumb I have used and it is basically similar to Randy.
Every piece of track is soldered to something, either a pair of feeders, or an adjoining track section which in turn is soldered to a pair of feeders. In this way electrical conduction is never reliant on anything but soldered joints. So on a long straight, the feeders might be 6’ apart. On complex track-work with several switches the feeders would be much closer together. I don’t like to solder my switches, so they all have feeders.
So IMO it is wrong to think in terms of feeders every x feet, but better to think in terms of electrical continuity.
On my layout I shoot for about every 6 feet but often turn outs have power issues with the contacts not making connections and loosing power so I power every end of the turn out and I do have about 15 foot section that has no power ran to the feeders… I ran out of the bus line wire and have not gone back to add more line to connect them to the feeders I installed when laying track. My trains run fine over the not connected to power section but I do plan on getting all powered up down the road because sooner or later I will have issues.
I suspect that the “every 3 to 6 feet” guideline comes from the 3-foot length of a typical section of flex track. I think it’s a pretty good guideline, and it works for me. I typically solder feeder wires to the underside of rail joiners, and use those to hold the tracks together. Sometimes I solder the track joints, and sometimes I don’t. If I find I’m having problems, I can always go back and solder a loose joint.
Even though you have working power distribution now, you can’t count on it always staying that way. Rail joiners do loosen over time, and scenic work with glue and paint will sometimes get into the joints and reduce performance further. Depending on turnout point contacts to route power is often another weak point in your distribution, one that will work well at first and gradually become less reliable.
Yes, I did a temporary layout once that only had feeders about 25 feet between. Had no problems but that was also real brass track not nickel-silver type. I would not recommend it to the general MR community. One thing to remember is that if the feeders are say 6 feet apart that means the locomotive is no more than 3 feet of rail from a feeder. So if n is equal to the distance between the feeders one must trust their layout rails to deliver the power in n/2 distance.
Our modular layout has one set of feeders per module (45"). Last operating session I connected amp meters to my module’s track feeders and watched the trains go by. One can tell the train is approaching as the current will slowly build up, peak as the tran passes, and then slowly return to zero as the train is on the other side of the layout.
Any particular reason you want to know why? Not knowing your level of electricity knowledge, I might point out that many colleges and trade schools have classes on electronics.
I solder the wires under the flex track. If you look at a piece of flex you’ll find a gap at the center of the section on the underside. This is a perfect place to solder the feeders. 6 feet simply places a feeder at every other flex section. As noted earlier you should also be able to short the track and have the breaker trip each time. Too much distance between feeders and that doesn’t happen.
Thanks for the answers guys. Texas Zepher, I guess that my reason is just plain old curiosity. Some people just like to turn something on, and as as long as it works, they’re happy. I, on the other hand, like to know why and how something works. I suspect that there is a fair amount of people in this hobby that are like minded.
My electrical knowledge is mostly self taught and gained from hands on experience. I did have engineer specific physics in college, but that was more about theory than actual practical application. My interest in electronics started very young. My father was an avid ham radio enthusiast. From there, I just learned more and more to the point that I can troubleshoot control boards on various equipment. I also do much of our in-house 3 phase speed controller and IEC controller circuit design and installation. I guess you can see why the specifics of DCC interest me.
Some of these answers actually pique my interest even more. I can see that this will already be more than just attaching wires. I’m sure that I’ll be doing some experimenting if for no other reason than to satisfy my curiosity.
I will add this. My layout is not yet finished. Neither are all teh bus runs (the bus would be in place, but I goofed and cut the wrong wires, thinking I was cutting the end of the staging bus at the last turnout, but it was the main track bus). So until I solder that back together, there isn;t even a bus to connect feeders to for about 1/4 of my layout. So while there are plenty of feeder drops int he area, none of them are currently connected. And everythign runs fine. I’m not about to leave it this way, btu there is an unpowered section of a bit over 3 sectiosn of flex track plus 2 turnouts. Probably about 12 linear feet of track.
ANd on my previous layout, which was basically an 8x12 donut hole double oval, when I completed the first main all the way around the loop, I wanted to test run a train all the way around, so I connected one set of feeders right to my Zephyr. That’s it, an 8x12 loop of track, with ONE feeder - 2 wires to the rails. Of course once trains rolled, construction slowed down - I probably ran it a month liek that until I got the second loop compelted and ran the bus wires and hooked up more feeders.
HOWEVER - prior to building that layout, I had a basic 4x8, although it was made with Bachmann EZ Track. I had 4 feeders equally spaced around the basic oval - and STILL trains slowed down at the spots furthest from the feeders. With both DC and DCC.
I have a 162 foot double main line (each main line is 162 feet), and my layout is powered by an NCE PH-Pro 5 amp system with a single booster. No separate power districts or circuit breakers, just one big power district. I have feeder wires to each main line, spaced about 9 to 12 feet apart. The feeders are soldered to the underside of rail connectors. All of my flex track is connected by rail joiners, most of which do not have feeders wired to them. Only the curved portions of my track are soldered together.
I know that my setup violates a lot of cardinal rules about wiring the layout. But, in my experience over a 7 year period with my current layout, the only problem that I have had with power interruptions is when the matte medium/water glue mix for my ballast gets under the rail joiners and causes a loss of power. When that happens, I simply remove and replace the faulty rail joiners with new ones. Incidentally, my bus wires are 14 gauge solid copper wire, and the feeders are 22 gauge stranded copper wire.
Rich, there is no doubt at all that one can wire a layout without the overkill of feeders advocated by some of us in this thread.
It reminds me of a joke my Grandad would tell…
A man sat in a train carriage, passing through rural England, throwing bits of paper out the window every mile or so. The conductor enquired as to why he was doing it? “It is to keep the elephants away” he replied. “We don’t have elephants here” said the conductor. “It works well then doesn’t it!”
Perhaps adding extra feeders is protecting against a problem that does not exist?
However, I would contend that for many the word “simply” in the phrase “simply remove and replace” would not apply to rail joiners for ballasted and painted flex-track that is well secured in place. I am not sure what method you use to replace a rail joiner in situ? but I would suggest that the small amount of effort to add a few extra feeders would save much grief and hassle. To my mind, having to replace a rail joiner on already laid track is in fact the very elephant we are trying to keep away!!
I absolutely agree with you and on my next layout I plan to wire feeders on the ends of every piece of 36 inch flex track. My response to the OP’s question was simply a statement of how I have wired my current layout, not a recommendation that others follow my past procedure.
Putting feeders every 3 feet is pure overkill. I have them spaced 9 feet apart on my layout, and I think even that is a little much as long as all rail joints have solder connections (with a jumper wire, usually).
My mainline bus is 14AWG with 22AWG feeders connected with IDC Scotch-loks. I have a Digitrax Zephyr located 25 feet from the end of my 200 foot mainline. I have no other boosters or circuit breakers (all one block). My trains run at a constant speed throughout my entire layout, and I’ve had this set up since the Zephyr came out with no trouble at all.
If folks want to spend extra money and do a heckuva lot of extra work for no gain, it’s not my problem. But there is trend in this hobby to overcomplicate things…and that leads to not only wasting money and time, but scaring off newbies. Before trying feeders every 3 feet, try every nine. See if it works. If it does, you’ll have saved time and money. If it doesn’t, you can always add more feeders later (which I seriously doubt).
You want overkill? I was given the advice by a few ‘old-timers’ at the hobby shop and elsewhere that I needed feeders on every piece of track. Every piece of sectional track. Every. Single. One. Now if that didn’t kill your joy for the hobby, I don’t know what will… or at least, it will kill your joy for electronics and wiring for the foreseeable future.
Well, unless you solder all your sectional track together, that’s probably good advice.
As previously noted a couple times in this thread, it’s very possible that over time, track joiners may become prone to bad connections from one section of track to the next. And if your next set of feeders in either direction is several track sections away, the problem could easily compound itself.
That’s why experienced model railroaders tend to shy away from sectional track and use flextrack instead. Using that same “old-timer” rule of thumb, you now have one set of feeders every three feet instead of every nine inches. And as also previously noted in this thread, if you solder every other flextrack joint you can probably do just fine with one set of feeders for every six feet of track.
So when you’re considering some piece of advice, or anything else for that matter, remember to also consider the context in which it was given or stated.
It’s overkill until you get a bad joiner. Then you forget and post here that you have a loco that is studdering or whatever. In the end you wind up adding joiners unless you do re-builds every couple of years.
This is why we tend to move to flex track after the first few layouts - instead of a joint ever 9 inches, it’s every 3 feet. Plus not limited to just the specific radius curve provided by the sectional manufacturer, most commonly 18 and 22 inch. There are a few others depending on the brand, but flex track is completely universal.