Can anyone help explain what this signal protects ?

Y Ddraig Coch

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Whilst out on a walk the other day I passed this signal. I have seen it thousands of times but have never given it much thought as to why it's there. But while so close to the track I noticed there doesn't seem to be a reason for it.

It is between Llandudno and Deganwy.

I always understood these signals to protect something. But I am baffled as to what it could be protecting.

It is on a long straight stretch of track, no points, no loop, no crossings nothing I could think it could be needed to protect. There is a distant just further down from this then another stop signal further down protecting Deganwy crossing so as I can see , no need for it.

Any help appreciated
20200502_181121.jpg20200502_181057.jpg
 
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edwin_m

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If the next signal in the direction of travel is a distant then this is the section or starter signal, that can't be cleared until the next box has given "line clear". While waiting for line clear, the signaler will probably bring a train up to the section signal so it can continue into the section as soon as possible. If the box has more than one stop signal in the same direction with suitable spacing, then the signaler can accept a following train and bring it up to the stop signal before the section signal.
 

Y Ddraig Coch

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If the next signal in the direction of travel is a distant then this is the section or starter signal, that can't be cleared until the next box has given "line clear". While waiting for line clear, the signaler will probably bring a train up to the section signal so it can continue into the section as soon as possible. If the box has more than one stop signal in the same direction with suitable spacing, then the signaler can accept a following train and bring it up to the stop signal before the section signal.

That makes sense. Many thanks.
 

Belperpete

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If the next signal in the direction of travel is a distant then this is the section or starter signal, that can't be cleared until the next box has given "line clear". While waiting for line clear, the signaler will probably bring a train up to the section signal so it can continue into the section as soon as possible. If the box has more than one stop signal in the same direction with suitable spacing, then the signaler can accept a following train and bring it up to the stop signal before the section signal.
The prefix is LO, which I assume means it is controlled from LlandudnO signalbox. If it is followed by Deganwy's distant and home signal, this would support that it is Llandudno's section/starter signal. Edit - as confirmed by John W.
 
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Belperpete

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I always understood these signals to protect something.
That is not correct - unless you include protecting the section of line ahead. There are very many semaphore signals with just plain line ahead.

The most common examples are starting or section signals, like the one you posted about, that protects the section of line between two signalboxes. Likewise, a signalbox may have inner and outer homes, with just plain line between the two. At one time, Deganwy box used to have inner and outer homes on the up line: if the signalman couldn't clear the inner home (e.g. because of a train ahead in the platform) he would caution an approaching train from Llandudno at the outer home, before allowing it to draw up to the inner home, which was much closer to the level crossing, and in view of the signalbox.

There also used to be a semaphore section/starting signal at the end of the up platform, where trains would be held if the section between Deganwy and Llandudno Junction were occupied (I think it is now a colour-light signal, but serving the same purpose).
 

Y Ddraig Coch

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That is not correct - unless you include protecting the section of line ahead. There are very many semaphore signals with just plain line ahead.

The most common examples are starting or section signals, like the one you posted about, that protects the section of line between two signalboxes. Likewise, a signalbox may have inner and outer homes, with just plain line between the two. At one time, Deganwy box used to have inner and outer homes on the up line: if the signalman couldn't clear the inner home (e.g. because of a train ahead in the platform) he would caution an approaching train from Llandudno at the outer home, before allowing it to draw up to the inner home, which was much closer to the level crossing, and in view of the signalbox.

There also used to be a semaphore section/starting signal at the end of the up platform, where trains would be held if the section between Deganwy and Llandudno Junction were occupied (I think it is now a colour-light signal, but serving the same purpose).
Very detailed reply thanks. Obviously as the line is much quieter now i dont believe the signal is ever used as such anymore.

I have never seen any train come to a stand at it in all my time of living here, close to it and using the line regularly.
 

Islineclear3_1

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I always understood these signals to protect something.
View attachment 77533View attachment 77534
The protection of "something" is the next block section controlled by the signalbox in advance. Assuming this is a section signal, it cannot be cleared until the signalman has confirmation (by the box in advance) that the line ahead is clear. The signalman cannot physically "pull off" this signal until it has been released by the box in advance after giving line clear

Unless there is a different local arrangement of course

Just out of curiousity, did you notice a white diamond on the post? It isn't evident in your picture
 

Y Ddraig Coch

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The protection of "something" is the next block section controlled by the signalbox in advance. Assuming this is a section signal, it cannot be cleared until the signalman has confirmation (by the box in advance) that the line ahead is clear. The signalman cannot physically "pull off" this signal until it has been released by the box in advance after giving line clear

Unless there is a different local arrangement of course

Just out of curiousity, did you notice a white diamond on the post? It isn't evident in your picture
No white diamond as far as I rememeber. 20200502_181058.jpg
 

Belperpete

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Very detailed reply thanks. Obviously as the line is much quieter now i dont believe the signal is ever used as such anymore.
I have never seen any train come to a stand at it in all my time of living here, close to it and using the line regularly.
The starting signal on the platform end allows a train to be brought into the platform while the section ahead is occupied. By the time the train arrives in the platform, the train ahead should have cleared the section, allowing the signalman to clear the starting signal. Without the starting signal, the train would have to be held at the home signal, before the platform, to wait for the section ahead to clear. Which would mean that, once the home signal could be cleared, the train would then have to stop again at the platform. And of course, a train held at the home signal would be blocking the section in rear. Signals are as much about keeping trains moving as stopping them.

Back in the 1970s, the line between Llandudno and The Junction could be very busy, particularly on Summer Saturdays. Not uncommon to have a train stood at virtually every signal between Llandudno and The Junction on both up and down lines.

One signal that was singularly useless was Deganwy's Down Distant, which was on the same post below Ll. Jcn's starting signal. The Deganwy signalman would close the level crossing and clear his signals when "Train Entering Section" was received from The Junction. By the time this was done, the train had long-since passed the distant signal. I never knew the distant signal ever used. There was a special bell code to warn Deganwy when a train was approaching The Junction (or leaving Colwyn Bay), to give the Deganwy signaller early warning to close the crossing and give the train a clear road, but this was only used for special trains. The only occasion I can recall a train being signalled with it, the section ahead was occupied so the signals couldn't be cleared anyway.

Another oddity that I recall from that era, was that Deganwy's up distant signal had its post painted with black and white stripes. I understand that was LM practice for isolated distant signals?
 

Llama

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The presence of a telephone and no white diamond is interesting then.

I don't know the area, how far is this signal from the signalbox? Is there another signal in advance worked by the same box?
The signal is just over half a mile in advance of the box. The next signal is DY5 distant signal, the next after that is DY6 Deganwy's semaphore home signal (again with SPT & no white diamond) then further on Deganwy's up section signal is a three aspect colour light, and Llandudno Jn's up home signal is again a three aspect colour light.
 

Belperpete

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The presence of a telephone and no white diamond is interesting then.
The white diamond indicates that a train standing at the signal will be detected. Track-circuits are fairly standard for home signals, to prevent the signaller from giving line-clear with a train waiting at his home. I did not think they were standard for starting signals.
 

Romsey

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LO9 is the section signal for the section to Deganwy.
As described up thread extra signal sections were installed to increase capacity.
It's also there to allow shunt movements on the up line without needing to obtain "shunt ahead into section" from Deganwy.
 

John Webb

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The white diamond indicates that a train standing at the signal will be detected. Track-circuits are fairly standard for home signals, to prevent the signaller from giving line-clear with a train waiting at his home. I did not think they were standard for starting signals.
According to the 1979 photo I linked to in post #6 above, there was a track circuit (T1) from the advance side of the crossover into the siding to signal 9. The point coming off the line into the siding had its own track circuit T2, but the other point and the siding itself had no track circuit. The crossover was operated by a local ground frame unlocked from the box. A look at the 2010 diagram on the same website indicates the crossover is now motor worked from the box; the track circuits remain the same.
I guess that the SP telephone was not installed for use when a train was held at the signal, as required by Rule 55 and its successors, but for use by the ground-frame operator and driver to communicate their intentions? And it's been left in place for similar communication between signaller and driver?
 

edwin_m

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According to the 1979 photo I linked to in post #6 above, there was a track circuit (T1) from the advance side of the crossover into the siding to signal 9. The point coming off the line into the siding had its own track circuit T2, but the other point and the siding itself had no track circuit. The crossover was operated by a local ground frame unlocked from the box. A look at the 2010 diagram on the same website indicates the crossover is now motor worked from the box; the track circuits remain the same.
I guess that the SP telephone was not installed for use when a train was held at the signal, as required by Rule 55 and its successors, but for use by the ground-frame operator and driver to communicate their intentions? And it's been left in place for similar communication between signaller and driver?
In this case I'd say there are good reasons for getting the driver to phone in if the train is stopped there. For example if there is a problem on the way to Deganwy the driver may need to be given special instructions. This could perhaps be done at the platform, but the signaller might want to get the train out to L9 before doing so, perhaps because there was another train approaching and needing to use the same platform. So the phone would be provided and the diamond plate not provided despite the signaller being aware via the track circuit of a train waiting at the signal.

I think the GF operator and driver would communicate by hand signals. If the train was a multiple unit the driver would probably be at the other end in any case. And that phone looks fairly new so may post-date the abolition of the GF.
 

Y Ddraig Coch

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I now understand why it is there. Thanks to all who have replied.

I suppose the next question is now Llandudno even at its busiest, i mean now not then, isn't that busy. Shunting that far out or to hold trains is never necessary.

So with the inflated costs of doing anything with network rail, are telephone s that need upgrading and maintenance of that signal which could easily be removed as doesn't really serve a purpose anymore or in recent times.

Who makes these decisions? As they remove the loops, the sidings and shunt limits. Is it laziness not to remove the unused signal , or is it future proofing Incase it is ever needed again?

When eventually the signalling ends up in Cardiff might it be a consideration to remove out fated and no longer needed infrastructure.

Or is it " if it ain't broke don't fix" it sort of attitude

Lots of questions I know..... more spare time than usual on hands. Apologies
 

Sheridan

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So with the inflated costs of doing anything with network rail, are telephone s that need upgrading and maintenance of that signal which could easily be removed as doesn't really serve a purpose anymore or in recent times.

Who makes these decisions? As they remove the loops, the sidings and shunt limits. Is it laziness not to remove the unused signal , or is it future proofing Incase it is ever needed again?
It’s not unused as such, the section signal is there as the start of the block section between there and Deganwy’s home signal. It could be sited nearer to Llandudno station perhaps, but there would be nothing gained from doing so. But it certainly couldn’t be removed.
 

Tomnick

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It’s not unused as such, the section signal is there as the start of the block section between there and Deganwy’s home signal. It could be sited nearer to Llandudno station perhaps, but there would be nothing gained from doing so. But it certainly couldn’t be removed.
You could abolish it, but then the platform starting signals would act as section signals - meaning less flexibility and some expensive design work and changes to the interlocking for a very small cost saving!
 

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