I am open to getting away from the bus, I did it that way because it was recommended on Allan Gartner's website (http://www.wiringfordcc.com/) and because it made sense. A priority with me, however, is comprehensible wiring. That is.. one should be able to look under the layout and figure out what is what pretty quickly. One of the things I am trying to do with my mini layout is come up with a system that accomplishes that.
For the sub-bus system, could I use a sort of common rail system for the feeders? That is.. have Rail A feeders all go to the main bus but have the Rail B feeders go through the detection ciruit via a "sub bus"?
The idea of running a seperate bus for each block like 60YOKID recommends would work. Right now I can test the block right at the block which is where I would be looking for the problem anyway.. so from that point of view, as well as its simplicity, I like the bus system. I think the actual mechanics of installing the more cost effective multiple block block detectors would result in lots of wires running around anyway.. there is some value of having them all go to the same place.
I do run all my stationary decoders (all being one right now) on a seperate line from my main bus and on the booster side of my breaker. That way, as others have suggested, I can still move my switch machine to clear the points when there is a short. I plan to run multi-wire strands out from a central decoder location to their switch machines. So.. it would be consistent with 60YOKID's idea too.
Anyway, lots of food for thought. I appreciate the feedback. Right now I can snip up my current bus to make a sub bus system.. once I actually have some detectors installed I will probably try a few different ways to see which feels best.
Chris
Gandy Dancer wrote: Through the years I have come to the conclusion that the bus theory is way-over-engineered solution too,
Through the years I have come to the conclusion that the bus theory is way-over-engineered solution too,
Guess you don't believe in Ohm's law either? 8-)
Just depends on how "bullet-proof" you want things. Adding in a "sub-buss" is a minor detail, it adds maybe 50 feet or less of heavy gauge wire in a basement. and 8 connections on the layout in question (4 blocks, 2 wires/block). Not a big deal in my book, but makes things almost indestructible and guaranteed to work.
Dave H.
Dave H. Painted side goes up. My website : wnbranch.com
60YOKID wrote:Well, I'll probably draw a lot of flack with this, but I am not a believer in a "Buss" for HO.
One of the things that brought me to this conclusion is on our club layout. It has a bus with more feeders than most people recommend. It so happened that in one of our main yards (with the steam locomotive facility connected to it) someone did some repair work on one of the control panels. When they were done they never reconnected the bus. We ran the whole yard for years (probably 3-4) before we discovered that all the power getting to the yard was coming in through one set of small gauge wire someone at sometime earlier had incorrectly installed directly to the track.
Well, I'll probably draw a lot of flack with this, but I am not a believer in a "Buss" for HO. I am a believer in the KISS theory.
I have 14 signal blocks, each of which is about 20-25 feet long and uses several #22 droppers. I ran separate feeder cables to each block. Each cable is kind of round shaped and has two #14 stranded conductors twisted and an overall jacket. (I would have used #16 but I had #14 on hand so I used it.) My longest feeders are about 40 feet. These terminate at my two Digitrax boosters.
It will be simple to insert an 1156 tail lamp in each feeder to indicate which block is shorted. It will be equally simple to insert a block detector in each feeder. This way, most of the electronics are grouped near the booster locations. The voltage drop is very low across 40 feet of #14 stranded and is not a factor with current detection anyway, since zero current flows until a load comes on the track.
I have 350+ feet of double track main line and I often operate 12 -14 locos at a time. About half are usually sound. Half are passenger trains with lighted cars. I have no power issues whatsoever.
-Bill
Sub-bus seems to be the way to go, thanks. If I am creative with the topology I think I can keep the extra wiring layer from making things too busy under the layout. I will probably just use the stranded 14 AWG I use for my bus but find a different color when I go to start my larger layout.
This would have the added benefit of making it easy to make my powered frogs part of the detection circuit.
MisterBeasley wrote:I would use a separate thick-wire sub-bus for each section. This sub-bus would be connected to the main bus through the detection circuitry, where you would otherwise connect a single set of feeders. All the feeders for a section would then come off of the sub-bus.
Same here. I use a 12ga bus, 16ga sub buses (through light bulbs) to multiple feeders. This let me feed every six feet but gap only in logical places.
Karl
The mind is like a parachute. It works better when it's open. www.stremy.net
In a word - a sub-bus. Say the stretch of track you want for the detection section has 5 sets of feeders (not uncommon if you attach feeders to every section of rail, which is a good idea to avoid any issues with rail joiners). Your main power bus runs aroudn the layout. Somewhere aroudn the middle of those 5 sets of feeders, you tap off the main bus to the block detector. The 'track' side of the block detector goes to a second, short bus that connects the 5 feeder sets.
Now if all the feeders for a particular detection section are very close, the 'sub bus' isn't necessary since feeder lengths will be short.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Chris,
A lot depends on how realistic you want your signaling system. If you just want a simple system that shows a block is occupied, then you can install one detector per block that lights up an appropriate nearby signal and uses "localized" wiring.
If you want to get more complicated and link signaling from block to block, or hook to computer, then you'll start to get the rat's nest because of the additional control and signal wiring you'll need.
I might suggest starting out simple and seeing if it meets your needs.
Mike Tennent
Sounds like the same question as this:http://www.trains.com/trccs/forums/687180/ShowPost.aspx
I would think the more "dectectors" in a single circuit, the more econimical it would be to have them out on the layout close to the track they are detecting. On the other hand if the detection is for a very large block and the dectector is on a circuit by itself, put it in the bus proper.
Gary UK wrote:All i done was solder jumper wires across the joints inside the block section and snipped all the feeders bar one. ... i only have plain line in the blocks with no spurs etc.
It takes an iron man to play with a toy iron horse.
Hi,
What are people's strategies for wiring a detection block that contains multiple feeders?
Right now I have a 14 AWG bus with 18 or 20 AWG feeders. I plan to use 22 on my larger layout, but I have some left-over solid wire from another project I am using up on my test layout. Its overkill but the point of this layout is to use the techniques I will use on the next one.
I have divided my layout into four logical blocks so I can play with detection and signalling. One block contains two spurs and a small run-around which has resulted in 4 seperate sets of feeders. Currently I have those soldered to my bus line in various places. I would imagine on larger layouts with longer blocks I will have multiple feeders just due to long runs of track.
How are folks wiring these to their detection circuitry? Do you "collect" them together on a terminal strip and run to the card then on to the bus, solder them together into an intermediary bus line, collect them where they enter the card (or go through in the case of the loop type), or some other better idea I have not thought of?
I have not picked out what I will use for detection right now, but I am wiring so that I can drop whatever I end up with later right in.
Thanks much,