Nice bridges.On the bridge that is mounted, I would have expected to see a single signal head over the second track from the left. You have two turnouts that merge into that track, so if they were set to merge, you would need something to stop the traffic on that second track before the turnouts.Also, I would have expected to see a second head for the signal over the third track from the left. My reasoning would be that the third track can be diverted just as the first and fourth tracks. (Unless I can't see the second head.)Please understand that I am not trying to be too critical, but trying to present correct information as I see it. I am also the signal go-to guy for our clubs B&O layout. We use CPL's with markers. Talk about hard to learn. Then I had to reduce the number of marker locations per signal so we could simplify the signals, but still be halfway correct without driving the engineers crazy with signal rules.Have you seen this yet?http://www.waynes-trains.com/site/Signals/GettingStarted/SignalsGettingStarted1.htmlIt may help you, or you may already know this information. I think developing a signal plan is critical. It will tell you where you need the signals and what types are needed. (How many heads). As we are signaling our club layout, a signal plan is made beforehand so we know what we have to do to make them work and what aspects they need to display.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
To update where we are with them, so far there are 3 bridges installed with many to go. Here are pics of the first 2. The first pic is before installation. The second is installed.
Springfield PA
I would also like to point out that the PRR used 2 types of signals. One was usually approach-lit & contained all amber lights and the other contained amber lights at the vertical & 45% spots, with the centerlight lit. The horizontal lights were red with no amber center. This signified a Dispatcher-controled signal and are constantly lit. The book "Railroad Signaling" by Brian Solomon contains a lot of information on signaling systems. I might also might suggest that if you are planning to operate by signal indication on your layout, you might want to simplifying the available indications to the basics,i.e.(clear, approach,stop, w/ the second head at interlockings to indicate diverging movements). This would help all members or guests to understand the system better. I know I don't want to take a rules exam just to operate at our club. This is what we have decided to do on our B&O / WM based layout despite being at least a couple of years away from a signal system. I wish your group success in your efforts & hope to see the results here or in print.
Anyhow, all this serves to illustrate why you need a rule book for the road and period you are modelling if you want to get everything just right.
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Absolutely and that rule book should be from the year(s) you model.
We had to call signals in the cab and we would use "Approach Medium" or "Approach Limited"..
IIRC I was told that was leftover steam era speak since the majority of the engineers and fireman had steam era experience.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
BRAKIE It appears to me some of those listed sites doesn't cover all the signal rules..They seem to cover the basics signals since I didn't see that many flashing signals.
It appears to me some of those listed sites doesn't cover all the signal rules..They seem to cover the basics signals since I didn't see that many flashing signals.
That website probably shows the signals in use in 1947 but I think more signals were added later on (Approach Slow, Medium Approach. Approach Limited, and Limited Clear come to mind)
The Limited aspects could be given either by flashing the lower head or with a yellow triangle on the lower head to "upgrade" the speed from medium to limited. Flashing was often used to "upgrade" a signal aspect. The limited speeds MAY have come about around the time the NY-Washington mainline was upgraded for the original Metroliner service in the 1960s. Incidently. IIRC, some freight men called Approach Limited and Limited Clear as Approach Medium and Medium Clear.
The deverging signal would be displayed as a Slow Approach or Restricting since you are making a conflicting move.If the interlocking was lined for your move you would be looking at a absoute stop since there is conflicting move.
I will add this for free..Passing PRR's signal test wasn't a easy task.I passed with the lowest allowed score.I only missed 2-both flashing aspects.
gandydancer19 http://mysite.du.edu/~jcalvert/railway/prraspec.htm The key is the signal RULE. Once you find the rule that governs the speed for a diverging track, then you can connect it with a signal aspect for that rule.
http://mysite.du.edu/~jcalvert/railway/prraspec.htm
The key is the signal RULE. Once you find the rule that governs the speed for a diverging track, then you can connect it with a signal aspect for that rule.
Looking at the 1947 signals given in the very interesting website above, and the example given by the OP:
If the crossover is lined straight through the signal on the bridge might display Clear, Approach Medium, Approach, Stop and Proceed, or Stop depending on what was ahead.
If the crossover was lined to "diverge" the signal might display Medium Clear, Slow Approach, Restricting, Stop and Proceed, or Stop depending on what was ahead whichever way the interlocking was lined.
Different railroads use different signals and a different number of heads on a mast. The PRR uses position lights and only two heads to display all of it's aspects. The ATSF may have used three heads in a searchlight style for it's signals. The B&O used color position lights (CPL's) and lunar markers.
For the PRR, you are looking for Rule 283 or 285A at the following link:
You may not find an example photo of the exact signal you are looking for on a signal bridge. Signal heads were mounted on a mast, as simple as it sounds. The masts were located on different signal structures. They could be a cantilever, a signal bridge, or a long mast. That is why most signal aspect rules just show the signal heads used to display a particular aspect. The actual heads can be mounted almost anywhere as long as the two heads used to display a single aspect are on one mast, and located one above the other, and not offset to the side of each other. (The C&O did this, offset their signal heads in some cases.)
However, if you are modeling the PRR, you can't use a signal head arrangement from another railroad. You can't mix and match, as you appeared to be thinking at the beginning.
Reading here and on the links I see that my original post of needing 3 heads would be incorrect since the charts and rules don't call for them. A single head or 2 heads at most look like they would cover everything. Am I reading it right?
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That is correct..Those signal aspects would cover all moves.
Thanks again all
Also Here's a post from another forum. Would he be correct?
Using the PRR PL Signals, there would never be more than two signal heads. The Top, would be capable of displaying clear (3 lights verticle); Stop (3 lights horizontal) or Approach (3 lights diagional right high, center, and left low). These would be the basic automatic block indications, The bottom signal head would capable of displaying the same aspects as above,except stop, plus the opposite diagional. These would be for diverting routes, such as crossing over from 3 to 2, or 3 to 4. These aspects could be Medium Clear, (Top Stop - bottom clear) for diversion with the current of traffic (3 to 4); Slow approach - a slow speed diversion with the current of traffic (top stop, bottom approach) or Restricting - against the current of traffic or with another train ahead in the same block - which is stop on top and permissive ie left high, right low on the bottom. A three headed signal would come in to the equation if using color light signals as used by NS or NJT vs. PRR PL signals. Google a NORAC signal chart to see the difference.
PRR did use a diverging signal aspects-I long forgotten the rules but,know these was used at junctions and for passing sidings.
We would get a form 19 authorizing us to crossover and run(say)the Westbound main between mile posts and that would usually be under restricted speed but,a 19 would not be needed to take a diverging route through a junction switch or into a passing siding since these was under signal rules.
Now a switchtender would line you out or in to the yard or passenger terminal and this would be under flag orders which was green-this insured the crew the the switches was is lined for your move and this would be done under restricted speed..If the switchtender displayed a yellow flag that would tell you that you wasn't lined onto the main by the tower operator- a lot of times we would be held at the towerman's signal for a conflicting move.This could be a dwarf signal-these was also known in PRR speak as "pots"..
"Stop on the pot John." and John would reply "stop on the pot".
Dave H. Painted side goes up. My website : wnbranch.com
The signal really has nothing to do with the turnout. There could be a hundred turnouts and one signal or 2 signals and no turnout. A single head would give a minimum of aspects. Usually stop, proceed, and slow. The dual head upper and lower quadrants would aspect all sorts of commands like slow approach, stop and proceed, Approach clear and clear would be a few. The PL signals mimicked the older semaphores they replaced. The blades were positioned the same as the PL lights. Like what was posted in the links. There could be one head or two heads per block but mostly there were one head and a single light bellow the head.
To break this down the signals control the speed of the block only. This has nothing to do with turnout direction. Time table and train orders control the turnouts.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
Thanks again for the info. I think I understand what both of you were explaining but still something that I can't get into my thick skull.
How do they determine the amount of signal heads over this particular track? Why would it be 3 and not 2 or even 1?
I still haven't seen a picture of a bridge with 3 full postiion signals over it and yet I've had a consistent answer of 3 when asking how many to use in the earlier scenario.
To screw it up a little more the digitrax SE8C manual shows a single signal head used with a turnout.
The speed correlation to the signals do make sense to me.
Thanks again.
Hamltnblue Thanks for the links. What I haven't found in any of them is a mention of scenario's where you have a turnout or 2 and how the signals correspond with them. This is where I'm not understanding. In other words I'm told that 3 heads would be over the track but no mention of how the heads relate to the 2 turnouts routing to two other mains. Hope I'm wording it right. The lightbulb hasn't gone off in my head yet.
Thanks for the links. What I haven't found in any of them is a mention of scenario's where you have a turnout or 2 and how the signals correspond with them. This is where I'm not understanding.
In other words I'm told that 3 heads would be over the track but no mention of how the heads relate to the 2 turnouts routing to two other mains.
Hope I'm wording it right.
The lightbulb hasn't gone off in my head yet.
When coming up to an interlocking it doesn't matter how many switches there are or what aspects thesignals for other tracks are displaying. The train is operated to conform with the indication given by the signal on its own track. The interlocking machine will not allow conflicting routes to be set or allow a signal to display an aspect that would allow too high a speed.
It's pretty hard to pick up signals if you don't know what the rules say for each signal (approach medium, medium clear, slow approach, etc.)
You might try going to
www.railroadsignals.us/
scroll down to and click on PRR PL (Position Light) Signal there is a chart that shows signal aspects and indications. It's kind of small to read on my laptop, but it might be clearer on a bigger screen.
The signals would not indicate what direction the turnout is lined for. When switching tracks the crew would follow the specific written order handed to them. This order would have the time and position/track they were to operate on. Most of the time the turnouts were lined for them by a nearby interlocking machine when it came to mainline running. The signal aspects would tell the crew what the best speed would be for that particular block or interlocking. Slow approach would be indicated if the train was switching tracks or there were traffic ahead. Stop approach would be indicated if there were oncoming traffic on the same line. Approach speed would be nothing faster than a safe stopping distance within line of site. This was up to the engineers judgement on how fast the train could go on approach. Read the links I posted and you can understand what the aspects displayed would indicate. Train orders always supersede signal aspects. A given signal could display a clear signal but carry a speed restriction in a given area. The signal being clear or proceed would indicate track speed of 50 for freight and 60 for passenger/ superior trains but there could be restrictions not indicated by signals. If for some reason a train was lined into the wrong track according to the orders given the train was required to stop and the front and rear brakemen would be whistled to provide protection while the conductor or engineer called dispatch at the nearest call box. If your orders were to take a siding at a particular place for clearance of a superior train it would be better to stop and switch tracks before the signal reads approach. If the superior train receives an approach signal before you are clear of the main then that crew could report a delay due to slow traffic ahead that should have cleared before the signal changed.
Hope this helps you understand a little.
"I think this is where I'm not understanding. What for instance does medium clear mean?" Medium clear can mean different things for different railroads. This is what you have to research. The first thing to do is find a PRR rule book or some reference that shows the variations of PRR signals. Next, you need to clarify the meanings of the terms used for the signal aspect shown, and what track arrangement the signal was used for. This is going to take some amount of research. Also, you need to think about how many aspects your hardware can display on the model signal. Sometimes you will have to make compromises because our model railroads can not cover the scale track spacing that the prototype would.
Here are three links that should get you started.
http://broadway.pennsyrr.com/Rail/Signal/aspects_us_pl.htmlhttp://www.rrsignalpix.com/pdfs.htmlhttp://www.rrsignalpix.com/links.html
I hope this helps.
EDIT: I just found this page which may be what you are looking for.
dehusman PRR did not use route signalling. They used speed signaling. According to the 1951 PRR rule book the following would be the indications for routes going through the diverging routes. Medium clear ; two heads top horizontal, bottom vertical. Slow Approach : top horizontal, bottom 45 degree angle (NE-SW)
PRR did not use route signalling. They used speed signaling.
According to the 1951 PRR rule book the following would be the indications for routes going through the diverging routes.
Medium clear ; two heads top horizontal, bottom vertical.
Slow Approach : top horizontal, bottom 45 degree angle (NE-SW)
I think this is where I'm not understanding. What for instance does medium clear mean? Does it mean route from the first turnout is clear, and straight thru and the second turnout are blocked?
I just got back from the club and took a couple of pics. This is the section in question. Track 1 is to the far left. The question is on track 3 with the bridge at the rerailer on the bottom of the pic. If there are 3 signal heads over track 3. What do each one of them mean? Is the top one showing status of straight thru(track 3) the middle the status of the first turnout to the right and the bottom the 2nd turnout to the left?
By the way there is full block detection in place as well as position of the turnouts.
Thanks again
Thanks
I've found dozens of links and some great reading but haven't found what I am looking for.
It's of course possible that I'm looking for something that isn't correct. I'm going on what has been told to me at the club. I'm wiring the signals and getting ready to build the first bridge but of course want it right.
Maybe if I just describe the section it would help. I'll drive over to the club and take a couple of pics of the spot and post them. Maybe I'm just not asking the question right.
Try googling "prr position light signals"
You probably need a signal with a full upper head except for the 135 and 315 lights, and a complete lower head (the lower heads didn't have 90 and 270 lights) The light numbers represent degrees of a circle.
In your area you can probably still see what you are looking for from the SEPTA station platform at Marcus Hook. Looking north from the northbound platform you can see the signals for HOOK interlocking, which should be just what you need. In PRR days all the lights would be yellow instead of Amtrak's red and green. If you go, stay on the platform and well clear of the tracks. People should be able to go on the platform to check the train schedule and hours the agent is on duty without trouble from the police.
Quick Edit: In SE PA you shouldn't have too much trouble finding an old PRR rule book, which would have sketches of the various signal aspects.
Here are a couple links to the PL signals that I have.
http://www.railroadsignals.us/signals/pl/pl.htm
http://mysite.du.edu/~jcalvert/railway/prr/prrsig.htm
I have never heard of the Pennsy using a 3 way switch. Not saying that they might have had one somewhere. When the Pennsy used multiple track they were set for Eastbound and Westbound. A single track usually was bidirectional and double track was single direction on each track. I would think that an absolute signal would be on the single track and a signal bridge would be controlling the blocks of mains. The switches would be controlled by a nearby tower or interlocking plant.
Try this
http://www.google.com/search?q=PRR%20signal%20bridge&rls=com.microsoft:*:IE-SearchBox&oe=UTF-8&rlz=1I7GGLL_en&safe=active&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi
Also, check your PMs.
sfb
Do you know where I might find a pic of one so we can place them right?
Also looking at your signature. Any relation to Lins Junction in Lansdale PA?
Please don't quote me on this, but I would think you would have 3 signal heads, one protecting each main.
Hello all
We're getting ready to start building signal bridges for the club layout.
Entering one area, one track (track 3) can go 3 ways. Straight through on mainline track 3, A turnout to the right to enter mainline track 4, and a turnout to the left to enter mainline track 2. We'll be using PRR position signals.
Would we have 3 signal heads or only 2 over track 3 and how would they be operated correctly?