Signals

[Scottew7]

Does anybody know of a web site where I can find information on bridge signals and block signals etc. . Where and why they are are placed on the track. Thanks

 

[Cjcrescent]

Don't know of any websites, but there are many books out on the subject. Most prototypes have published material about their signals, for their employees, and you may find these at used book dealers, hist societies, etc.

Look on several of the model railroad publishers websites in their book depts. John Armstrong's first book IIRC was about signals, but its probably OOP.

 

[fiend540]

Straight from the source, I asked this question on the Conrail Modeler's yahoo group and someone provided me this link. There's a lot of good information in here

http://thebecketts.com/images/NORAC 8th Edition NJT.pdf

 

[tankist]

was looking for switch machine circuits and visited the site below. perhaps not very prototypical but here is "simple railroad signals" concept.
http://home.cogeco.ca/~rpaisley4/SimpleSignal.html

from what i see the idea is to protect ocupied blocks with stop, the one right behind with approach,while rest remain clear.
you can apply your own idea as to what aspects to display on detection.
EDIT:
here is the SCX signal rules PDF
http://cg-tower.com/cpl/operations/CSX Signal Rules.pdf

 

[lmackattack]

just going to chime in here. Im model Railroading to set up signals so that they function like real world railroads can be a electrical nightmare. Not just the instalation but the maintaining of them. Digitraxx has some nice ways to control them but its alot of $$$. Simple signals operation could be that all remain dark untill one block ahead becomes taken. or they all stay green untill a block is taken. this would be the cheap and simple way to use them on a layout. this is how I use them on my home layout. when you start controlling crossovers with 2-3 track mainlines...have fun!!!!

 

[kenw]

http://www.logicrailtech.com/

go to Signal Rules tab

 

[NYC_George]

Signals control the movement of trains through blocks. Their mostly used to control the speed of trains although some signals do add, in example - be prepared to stop at the next signal or second signal. Signal’s that protect passive blocks have number plates on them. If the signal is red and has a number plate you would stop and proceed not exceeding more than 15 mph looking out for another train, broken rail etc. You wouldn’t be able to exceed this speed until a signal with a better aspect was encountered. A red signal without a number plate used at interlocking or an absolute block, where a train order would come into play cannot be passed. In North White Plains where I spent some time switching passenger cars yard signals had only 2 aspects. If a dwarf yard signal was lit white it was ok to proceed. If it was out you stayed put.
On the main if you’re crossing over from track 1 to track 2 you would get a medium clear - red over - green - over red. Proceed at 30 mph the next block is clear. It doesn’t imply your crossing over just get down to 30, but you’re usually crossing over. If it was a high speed crossover then it would be red over - blinking green – over red. Get down to 45 mph the next block is clear. If you encounter a yellow over yellow then there’s most likely a train 2 blocks a head of you, but maybe not. Just get down to 45 mph being prepared to stop at the second signal. Red over Red over Green is slow clear do not exceed 10 mph. Most of the time this aspect is used in tight turn interlocking. We would encounter this signal at DV on the Hudson where we crossed over the main lines into New York City's west 72nd Street yard.

NYC_George

 

[Trouble]

i'm guessing you are modeling the norfolk southern? if you want to be a real stickler, almost every railroad has it's own use of signals aspects and the NS definetly has some different signalling! as was stated above, the basic idea is similar to traffic lights. green, or "clear" means go, at your maximum authorised speed. yellow is called "approach" and is just like a yellow traffic light, it says be prepared to stop before passing the next signal. An approach usually has a speed restriction applied to it, on the NS it's reffered to "medium speed" which is defined as A speed not exceeding 30mph. The rule accord ing to the NS is defined as Proceed preparing to stop at next signal. Train or engine exceeding Medium Speed must at once reduce to that speed. Red, or "stop" means, well, stop. But with the NS, you have what they call a "restricting" which is all red with a number plate below the signal, or a red signal on top with a yellow below it. An all red signal with NO number plate is just called "stop" A restricting signal's instructions are Proceed at restricted speed. And of course Restricted speed is a big one. The version i am reffering to is in the NS version of the CORA, but is pretty much the same everywhere. It's defined as " A speed that will permit stopping within half the range of vision, short of train, engine, obstruction, railroad car, men or equipment fouling track, stop signal, derail, or switch lined improperly and looking out for broken rail, but not exceeding 15mph. basically if you can see clearly for a half mile, you need to be able to stop in half that distance, or 1/4 of a mile. There is no need to stop and then proceed on the NS it seems. how it basically works is, say you have two trains and one track. block or occupancy signals are typically placed about two miles apart. Say train "A" is at milepost 16, stopped. the signal behind it at MP 14 would be displaying red, or for the NS it would be called a Restricting. MP 12 would be yellow, or approach, and 10 would be green, or "clear". In front of "A" the signal at MP 16 facing the other way would be red, at 18 it would be approach, and the others would be clear. as "A" moves and the rear clears the signal at 16, the previously red signal at 14 will go to approach, and the approach at 12 will become clear. now if train B is following, that aproach signal will act as a buffer, letting him know that he is catching up and the next signal 2 miles away will probably be red, with a caboose or EOT behind it! Now, train B can pass that red signal if he wants to, provided it has a number plate. he can get right up on train A's rear if it's stopped, or hang back where he won't be blocking any roads or interlockings or anything

 

[Trouble]

That's just the extremely simplified, block signalling system. I didn't bother with stuff like an Advance Approach. And beyond the automated block system (ABS) you have CTC, or Centralised Traffic Control which is used at controlled sidings, interlockings, junctions, and some stations and yards. On the NS alone you have diverging signals, lunar signals, distant signals... you could probably spend years trying to adapt it to a model railroad!

 

[Scottew7]

Thank you guys very much for your time. You have all helped tremendously. For now I don't thing I am wiring any signals accept for the crossings. I am not a electrician, but maybe I'll we be after a couplle of years on the layout. I just want to place them were they would really be.

 

[NYC_George]

This happened to a train I was on in 1969. We had a 40 car freight that was running late on it’s return trip from the yard in west 72nd street New York City. That night we decided to put the caboose behind the engine rather than on the back of the train it’s usual position. We didn’t take siding that night because we were late. So we stopped on the main in North White to pick up some coffee. The 4 am local stopped and proceeded at the automatic block signal that was protecting us and saw ahead to the next signal that was green but didn’t see our train in the block. He ran into the back of us with the local and thank God no one got hurt. At the hearing he said although he looked ahead he was unable to see the beaten up box car on the rear of our train.

NYC_George