Planning for Signals: Need Help!


RexHea

RAIL BENDER
Ok, fellows I am about ready to get serious with making plans for signals on my large home layout. What do I know? Not much! All I know about Railroad signals is...there is a red, a yellow, and a green light:eek: . I have a strong background with electronic/electrical hardware, but can only work with user friendly/high level programming. My system is a Digitrax Chief-200 with Lenz LS-150 stationary decoders for turnouts.

What I want to accomplish is to have block detection that would have feedback to signal lights on the layout, physical display panel, and a computer user interface. Right now, I have no desire to have automatic running of trains, but I do want automatic signals and the ability to control turnouts with the computer interface. I am not trying to model an exact prototypical control system, but would like to have one that makes sense to the average operator and is realistic in operation.

Questions:
1. Where do I start? Do I begin with determining where the blocks should be located?

2. How do I determine the best location and size for blocks?

3. Where is the best place to locate target signals?

4. What kind of hardware is needed?

5. Sources of hardware?

6. Software for computer and sources?

7. And other questions that I'm too dumb to know to ask:D ??

Any and all help would be greatly appreciated.
 
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Rex, I think I'd start by getting a mental plan of how to block the mains. Keep in mind, for three aspect signals, you're going to need some reasonably sized blocks. Your printed track plan might be helpful to draw this out. Any sidings will need signalling. For the yards at the mine, lumber mill, and steel mill, I'd probably just use dwarf signals, if any at all. For the main yard, dwarfs would be great and a signal bridge leading to the main would be WAY cool. An informal operating session might help show where some of the signals need to be placed on the layout. That's something you might consider.

If it were me, I'd go with a Digitrax boards since you've got their system. Keith may well be at the ARG meet this month. He can give you some very good prices on the electronics and is a great guy to deal with.

We'll get Ray to give you a checkout on his signal system. I think he can control most of the layout (including turnouts) on his PC.
 
Ok, I have checked out all the links you guys posted and appreciate the help in getting a reference file going.

Has anyone setup the JMRI for a computer generated control panel? It seems to do what some of the more sophisticated and expensive softwares do. I just don't want to get in a corner later on and find out the software isn't capable of the "whole thing". Anyone have advice on software?

Do you know of any links to sites that have some examples of laying out a signaling system for MR?

Eric: You have some good ideas.
When I installed my track, I setup some blocks where I knew they would be needed because several are long runs of hidden track.
Most of the blocks are still there, but I have made so many changes since then I will have to make some modifications to have three aspect signals. In fact, I will have to see if it will help or be confusing for the three aspect. A simple go/stop signal may be the easiest for ops, but not really what I want.

I have a bunch of dwarfs that I will use for sidings off the mains and wasn't going to put anything in the yards as they are all ground throws and will be color coded. I thought that I would use the target pole/bridge types (??) for block occupancy only.
 
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I think as a general rule, you should have a signal at every switch, in both directions. Those will control the trains as they're passing by/through, etc. For switches in urban areas, like street running, I don't know for sure. But, out where trains normally are, you should have some sort of signal.

As far as blocks, the block size should hold your longest train. Remember that each train affects 5 blocks, the block it's in, the block it just exited, and the block prior to that. Plus, it will affect the block it's headed into and the block beyond that (that one will give a warning to diverge into a siding if there's an approaching train).

On my little empire, it's not big enough for all these blocks, so I only put signals where there is a switch.

Kennedy
 
HaggisKennedy said:
...As far as blocks, the block size should hold your longest train. Remember that each train affects 5 blocks, the block it's in, the block it just exited, and the block prior to that. Plus, it will affect the block it's headed into and the block beyond that (that one will give a warning to diverge into a siding if there's an approaching train).Kennedy

Yikes! I didn't think about all those blocks. I need to scratch my head a little harder to consider all of them.:confused:
 
Well, that's the way today's prototypes do it. CTC is set up so that you don't go from a green block to a red block. You *HAVE* to have an intermediate (yellow) block in between; the train can have time to slow, and it gives the hogger a warning to expect something up the road. Some roads have 'home' signals, which will give you the signal aspect *two* signals away.

I'm not real sure how it was done in the '50s. You may want to see how the Pennsey, or B&O, or NYC or GN or SP did it and work up something. It appears that you're road is freelanced, so you won't have to have an exact duplicate, but as long as you follow the appropriate standard of the day, you''ll be OK.

Doesn't the GCOR have signal aspect data in it?

Kennedy
 
OK, forgot this. Do a search on "Automatic Block Signals". That will give you a list of sites which explains how these things work. That'll give you a background so when you do your thing on your layout, it'll make sense.

BTW, somebody on another list set up block signals on the cheap. He bought a pile of those cheap-o Bachmann two-position signal stands. He drilled out the back of the green lite and glued in a mini LED. The lead was fastened to the legs of the signal stand, and wired to a toggle switch. I was all powered by a wall wart, I think.

All he wanted to do was to show HIGH GREEN, by flipping a switch. Dark meant STOP on the RR. It was manual switch flipping, but that's how CTC is done anyway; the dispatcher flips the switch to route. No RED ASPECT was shown. Simple and cheap...

:D

Kennedy
 
Sorry fellows. I just realized that my last post must have fallen into the Black Hole during the server upgrade. All I posted was a thanks for addition web sites and that I was amazed at the hits on a search for ABS.

I guess now is the time to dig into my track plan and start figuring out where to put the blocks. I will post more as things develop.
Thanks again.
 
Rex,
I have a background in electronics and designed/built all my signal electronics from TTL gates and opto-electric sensors between the rails. The amount of logic to drive the signals for a typical passing siding is fairly large. It will fill a wire-wrapped circuit card 4x6 inches. This includes approach signals and siding exit signals. I have all my sidings signaled now, but this is a large task. If I were to do it all over again, I'm not sure I would have done it any other way. IF you were to use a computer, I think you could write a BASIC program to read block occupancy detectors. You would also need to build occupancy detectors and then some kind of serial interface to tie it to the computer. I assume all this stuff can be bought too, but it would be half the fun to actually figure out how to do it yourself.

Bill
 
Hi Rex ( and of course everyone else too!) Don't spend any money yet until you guys see the layout here ! Hope to see you guys soon ! ( ARG MEET ) . Ray:)
 
Bill, thanks for the post. I have thought about getting the cobwebs out of my watered down 'Spice' software (and my brain) and make an attempt to design my own system. It could be a hobby within a hobby, within a hobby, within ...., and have the possibility of allowing for more and even different combinations of operations now offered by the manufacturers. I know it would be a lot of fun and certainly sharpen my mind, but for now I believe component level design would take more time than I have to give up.

Concerning block detection, the one that I have found to be interesting is the one based on current sink within the block. By sensing a 'power user' in the block, you have continuous detection throughout the block. I am still not that learned about this system, but the concept certainly is worth looking into.

Ray, I am looking forward to my visit at your Depot and very interested in learning how you setup your signal system. I will bring my notepad and I hope you are ready for a deluge of questions. See you Saturday!
 
Rex my friend,

I see you have more than enough info to get you going and keep you confused. Yet I can't walk away without my two-cents.

I ran on CTC with the WCL. There were two types of signals installed along the line in CTC territory. Intermediate, and ABSOLUTE.

Intermediate signals control the flow of traffic according to what is in the block ahead. But they do NOT govern movement through a control point ie,..interlockings, turnouts, etc,.. They also govern movement in that some intermediates are referred to as 'approach' signals. These signals govern the movement(speed) of a train that is approaching an ABSOLUTE signal. Intermediates can display most of the following aspects; clear(green), approach(yellow), restricting(red) and so on. Some railroads require a train to stop and proceed if encountering a restricted signal, while others allow the train to keep moving. The rules for signals are as different for signals as paint schemes are for railroads.

Absolute signals are just that, Absolute. They control movement through interlockings, turnouts, junctions, and anywhere else a train must make some sort of a conflicting movement with other trains. They are (usually) marked by an 'A' or the absence of a number plate (again railroad specific). If one of these is red, a train MUST stop before passing the signal. HOWEVER, a dispatcher has the authority to 'talk' you by one of these signals. Again some aspects include (but not limited to) ; Green=Clear/proceed, Yellow=approach prepared to stop, Flashing Yellow= approach next signal prepared to pass it a reduced speed, Red=STOP, Lunar(white)=Restricting/must make movement prepared to stop within 1/2 the range of vision for any obstruction(not the EXACT rule but you get the picture), and many variations of these are possible!

Rex, I don't mean to confuse, I just wanted to give a little 'insight' to you and maybe help answer some questions about CTC. Course if you go track warrant you wouldn't need signals at all;) .

If I can answer anything else, please ask.

Johnny
 
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Thank you Johnny for a wealth of information. It certainly helps me to figure out what is going on and I am sure others can benefit from this. I believe one of the most interesting facts that have popped up is the lack of a standard for all the railroads. I guess it doesn't matter all that much since they mostly use their own tracks. Actually, this is a plus for a freelance modeler in that he can easily say, "...well, that's the way it was done on the ---railroad.";)

I would like to encourage all to post in this thread with any knowledge or questions they may have about signals and planning for layout signals. I realize that many do not bother having them, but the reason may just be a lack of understanding them, as myself. Thanks all.
 
Hey Rex. I've got one little tech tip Ray and I talked about last night that you may want to keep in mind. The track power indicator LED on a UP 5 will draw enough current for a BDL168 to tag the block as occupied. You'll need a separate track power buss for the UP's if you want the LEDs to function correctly. I also suggested a "mini block" between detected blocks as a way around this problem. What I'm thinking is a mini block of maybe 1" that obviously isn't wired to the 168 but is wired to the UP's indicator light to show track power status. Things to think about... :)

ETA. I found a site that may interest you. Some of the graphics weren't loading for me, but it's some good info... http://broadway.pennsyrr.com/Rail/Signal/aspects_us_sou.html
Notice that the chart shows a reference the rule number they pertain to. The info CJ gave you might cross over to these aspect diagrams.
 
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Thanks Eric for the heads-up. Right now I don't use the LED power indicator on the UP5 so I am in good shape there. After seeing cprman's signals, I know why you are so excited about them. Gosh, they sure add a lot to the realizism and really make it easy for multiple users to avoid pasture sidings and head butts.

Also appreciate the link. I like the simple way they show all the signals.

:)
 
Just thought that I would add a note. I found loads of information on planning and wiring layout signals at the Digitrax web site. You have to go to the Manuals section and download some of the actual equipment handbooks, but they are loaded with 'how-to's'.
Now to study :confused: and study :confused: and study and...
 
Eric: I have been planning the location of detection sections and one question keeps coming up.

If I break up a hidden track into two sections, then when I have a train entering one end the light at the other end will show "Yellow". Now a train is approaching the other end to enter the hidden area. He see's "Yellow" and proceeds forward. OH,OH! Now what? K-a-bang!! Right?
 



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