Positioning of signals

[AyJay]

Hello, I have not posted in a long time.  I have a question about semaphore signals and I have looked on a couple of websites describing their use, but they don't answer the query that I have, so I'm hoping that there's someone knowledgeable about the use of semaphore signals who can help me please.

 

My layout is BR steam, OO gauge and I am using upper quaTrackplan_V10point8_a3.pdfdrant semaphore signals that I'm making from MSE (Wizard) parts.

A pdf of my trackplan is attached, so I'm hoping that it is visible once I post.

 

All of the signals are numbered with the letter 'S' as a prefix and in bold black type (to distinguish them from the point numbering). They number 1 to 6 from right to left on the UP mainline (clockwise). Also 7 to 11 from left to right on the DOWN mainline (anti-clockwise). I have left out the ground signals for now.

 

I took my trackplan with me to the recent London exhibition and spoke with one of the skills demonstrators from The Model Railway Club about signals, he said that he was a retired signalling engineer and he marked my plan for me. However, as I place the signals on the layout, something does not look right?

 

1. On the UP line, S5 is a DISTANT and S6 is a STARTER. But shouldn't S5 also have a STOP to guard the point after it, that is the exit from the goods yard?

 

2a. On the DOWN line, S9 is a STARTER and S10 is a STOP, to guard the point after it that is the exit from the engine yard. But then shouldn't S9 also have a DISTANT?

2b. The distance between S9 and S10 is very small, it is less than the length of a six carriage train, such that when the engine is stopped at S10, S9 is positioned midway down the 5th carriage. So should I just dispense with S10 and use S9 to also protect the exit from the engine yard?

 

3. Although not marked on this plan, another signal was also marked for the exit from the goods yard, and positioned close to S5. But it is not clear from the pencil scrawl if this is just a STARTER, or does it also have a DISTANT?

 

4. There was no STARTER marked for the exit from the engine yard. Should there be one?

 

5. S11 was marked as a STOP, but shouldn't it be a DISTANT?  For the purpose of this layout, all of the points for the fiddleyard are considered 'off stage'.

 

It would be much appreciated if someone can clear up these queries for me, as i said, the websites that I looked at were no help.

 

Thank you

[AyJay]

Hello, I have not posted in a long time.  I have a question about semaphore signals and I have looked on a couple of websites describing their use, but they don't answer the query that I have, so I'm hoping that there's someone knowledgeable about the use of semaphore signals who can help me please.

 

My layout is BR steam, OO gauge and I am using upper quaTrackplan_V10point8_a3.pdfdrant semaphore signals that I'm making from MSE (Wizard) parts.

A pdf of my trackplan is attached, so I'm hoping that it is visible once I post.

 

All of the signals are numbered with the letter 'S' as a prefix and in bold black type (to distinguish them from the point numbering). They number 1 to 6 from right to left on the UP mainline (clockwise). Also 7 to 11 from left to right on the DOWN mainline (anti-clockwise). I have left out the ground signals for now.

 

I took my trackplan with me to the recent London exhibition and spoke with one of the skills demonstrators from The Model Railway Club about signals, he said that he was a retired signalling engineer and he marked my plan for me. However, as I place the signals on the layout, something does not look right?

 

1. On the UP line, S5 is a DISTANT and S6 is a STARTER. But shouldn't S5 also have a STOP to guard the point after it, that is the exit from the goods yard?

 

2a. On the DOWN line, S9 is a STARTER and S10 is a STOP, to guard the point after it that is the exit from the engine yard. But then shouldn't S9 also have a DISTANT?

2b. The distance between S9 and S10 is very small, it is less than the length of a six carriage train, such that when the engine is stopped at S10, S9 is positioned midway down the 5th carriage. So should I just dispense with S10 and use S9 to also protect the exit from the engine yard?

 

3. Although not marked on this plan, another signal was also marked for the exit from the goods yard, and positioned close to S5. But it is not clear from the pencil scrawl if this is just a STARTER, or does it also have a DISTANT?

 

4. There was no STARTER marked for the exit from the engine yard. Should there be one?

 

5. S11 was marked as a STOP, but shouldn't it be a DISTANT?  For the purpose of this layout, all of the points for the fiddleyard are considered 'off stage'.

 

It would be much appreciated if someone can clear up these queries for me, as i said, the websites that I looked at were no help.

 

Thank you

[Andymsa]

Had a quick look

 

S5 should as you say Have a stop signal

 

S9 should have a distant if S10 is the next box home signal

Edited June 3, 2018 by Andymsa

[AyJay]

Had a quick look

 

S5 should as you say Have a stop signal

 

S9 should have a distant if S10 is the next box home signal

 Hello Andy,

Thank you for that, I'm pleased to see that you were able to see my plan.

That seems to settle the matter of S5.

S9 and S10 are both under the control of the signal box opposite the engine yard.    The other signal box, by S6, is the start of the next block which disappears off the end.

[Andymsa]

Hello Andy,

Thank you for that, I'm pleased to see that you were able to see my plan.

That seems to settle the matter of S5.

S9 and S10 are both under the control of the signal box opposite the engine yard.    The other signal box, by S6, is the start of the next block which disappears off the end.

S 9 then should not have a distant

[The Johnster]

Can't see your plan, but where boxes are too close together for the 'second' box's distant to be a separate signal on it's own post because the braking distance required (440 yards IIRC), it is placed as the lower signal on the 'first' box's section signal, i.e. it's starter or advance starter.  

 

A distant can be a fixed board signal if the line speed anywhere in the station limits or section if protects is lower than 40mph.  

 

You seem to have a fairly adequate understanding of the basic principles!

[Happy Hippo]

There doesn't seem to be any signal protection leaving the engine shed and goods yard.

[Flying Pig]

By having two signalboxes you have created a block section through the platforms (from s8 to s9 on the down line and from s5 - which needs a stop arm above the distant - to s6 on the up). This is not absolutely wrong but it does make life more complicated.

 

The situation would be much simplified by abolishing the left hand box and bringing all points and signals under control of the remaining one, and I think this would likely have been done by the BR period. None of the distant arms shown on the plan would then be required. I think you could also get rid of stop arms at s5 and s9, as I don't see what operationally flexibility they add.

 

S11 is an advanced starter, but unless you are shunting long trains into the loco yard, it could be brought much closer to the box.

 

As noted above, shunting signals are required to control movements in and out of the yards and over crossovers. The precise type and placing of these are quite dependent on time and place so I'll leave the details to the experts.

 

I'd prefer to see a single slip on the goods loop - it would be worked more as a double ended siding in real life and no facing access would be needed.

[TheSignalEngineer]

Unless the points marked as 11a are more than a scale 350 yards from the signal box by the engine shed then only one signal box is required. If more than 350 yards they could be motor worked. This simplifies the signalling somewhat.

I would agree that a single slip would be more prototypical for the siding connection thus removing the need for a facing point in the main line.

Edited June 3, 2018 by TheSignalEngineer

[TheSignalEngineer]

Sorry if a bit disjointed but am trying to type on a phone and a dodgy internet connection.

If only one box is provided there is no need for any lower distant arms.

Distant signal S1 is likely to be off-scene as even at 60mph it would be threequarters of a mile from the Home signal.

If the siding connection is a single slip S4 is not needed.

S5 should be a Home signal.

S6 is too far forward and should be moved back clear of 11b points.

Signals S7 and S11 are OK but I can't see a need for both S9 and S10.

All other moves would most likely be ground shunt signals.

[AyJay]

Thank you all for your replies.  As we all appreciate, a model railway is a compromise at all sorts of levels; compressed space, stretched time, suspension of reality and so on.

This project is already well into its construction and some things are impractical to change now.  If you care to look in May edition of BRM, there are photos of it in the readers page.

Taking what has been said, combined with what I picked up from that website 'The Signal Box', this is my plan:

Keep as is.

2nd signal box, cos it's already built and the point rodding is in place. Also recommended.

Double slip 6a/5a due to rising costs and ballasting is almost finished. Ditto Junction signal S2-S4.

Signals S7-S9 don't need changing.

Move.

S6 to end of platform so that it is clear of point 11a.

S11, if possible (entire right module is a viaduct and there may not be the room to place in middle).

Remove.

S10, mainline protection of point 21a will be provided by S9.

Change.

S5 will change from DISTANT to HOME.

Add.

S1 is behind a road bridge, so it needs a high-level repeater.

S5b to protect entrance to mainline from goods yard via point 9a/9b.

S10b to protect entrance to mainline from goods yard via point 5b.

S10c to protect entrance to mainline from engine yard via point 21a.

A DRAW-AHEAD signal to be added to S6.

S7/S8 are behind a road bridge, so a high-level repeater of the STOP S8 is required.

Planned, but not marked on diagram.

There will be reversed ground signals at points: 11a/11b. 9a. 6b and as required on engine yard.

 

I think that covers it all, have I missed anything?

[DCB]

Leading on from the helpful replies above, the questions this track plan generates in my mind are, 1) When was the area last resignalled?   1890s?      2) why is there a turntable at such a modest wayside station? 

3) Where exactly is the station supposed to be in relation to the next off scene signal boxes.

 

I would have thought that the signal boxes would have been rationalised by the 1950s, they are so close together and the left hand one has so little to do that it would surely have been switched out for most of the time by the 1940s.

 

My loft layout rationale was a similar ish station plus loco depot plus marshalling sidings placed just down the line from a junction where the line to a medium size town's terminus branches off a predominantly goods line.  Cheltenham Malvern Road and St James being the inspiration.  The station would be within the town, maybe the opposite side of a hill to the terminus.

 

That way the on scene loco facilities would serve the off scene station and give reasons for its existence, locos leaving tender first to pick up trains in the hidden sidings anc returning tender first after running the trains to turn and depart again tender first.    Also the station could reverse Push Pull  Auto trains (as did Malvern Road) which would require the right hand signal box to open if a non auto fitted loco appeared on the working and had to run round.

 

Under my scenario  Signal S11 could be  the double arm starter / advanced starter for the signal box in the right/ middle  with the distant arm for the next signal box anti-clockwise on the next post. Obviously this would be slotted so the distant arm could not show clear when the starter was on!    Otherwise turntables were not provided and maintained without some need, either real or imagined and were usually removed and re used elsewhere if traffic was insufficient to need their retention. It is only post steam, 1965/6/7/8 that turntables have been left in place for (very) occasional use.