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Trivia: Signals That Never Show Green

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Sprinter107

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SJ89 approaching Stourbridge Junction wont show a green for trains going onto the extension line.
 
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Deepgreen

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Never* display it or cannot display it? Important distinction.

If latter, there would usually be no green lamp fitted full stop.

*Signals will always be able to display in certain conditions, e.g. testing or when traffic levels are low.

So, for "never" read; "occasionally", by this definition? It seems then, that all signals will, under certain circumstances, show any aspect with which they are fitted. Perhaps the key is your use of "usually" - it's the unusual that the OP is seeking, I imagine?
 

MadMac

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E510 and E512 at the east end of Haymarket never seemed to get beyond a double yellow but were capable of displaying greens.
 

Deepgreen

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BN133 and PN106 seem to fit those criteria and there are other interesting examples which are related. I'd say it's a pretty good investigative thread so far.

Perhaps you could post a constructive example if you are not satisfied with the quality of the material, rather than just complaining...

I have no examples and have not attempted to add any (I'm actually not especially interested in this particular topic), BUT my frustration arises from the unwillingness of so many actually to read the request made and to answer accordingly, rather than just 'scatter-gunning' irrelevant examples about. It's a general point about the amount of irrelevant stuff posted on threads, crystallised for me by this particular example, and it's all too common on this forum (and many others, I imagine).
 

Sprinter107

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BA3633 between Bromsgrove and Stoke Works csnt show a green aspect for trains routed towards Droitwich.
 

adrock1976

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What's it called? It's called Cumbernauld
On the northbound platform at Barnhill, although there can be a myriad of signal aspects on display, under normal circumstances and in most instances it displays a single yellow aspect with the platform number that the train is routed into at Springburn.

Even when trains reversed direction at Springburn to and from Cumbernauld between 2014 and December 2018, the signal at Barnhill never displayed a green aspect.
 

ComUtoR

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VS178 can't show a single yellow when routed towards the 'Up Chatham Main' It also, must show a Junction Indicator. There is no 'main aspect' indication.
 

Adsy125

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Don’t know the number, but I can’t imagine the signal off allowing access from the Weymouth Harbour tramway to the mainline has shown a green aspect for a long time.
 

driver_m

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Speke used to have a signal that couldn’t show a green, because the Transformer had expired, and the replacements were getting very rare at the time, and so was fixed to show 2 yellows at best. (Very early 60s 4 aspect). Signalling engineers could better explain why. Euston has 4 aspect heads that can only show 2 yellows on the approaches. Lime St used to have these too.
 

driver_m

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As an aside. Any signal that has a code 2 AWS failure. (AWS doesn’t sounds bell in cab, but sounds horn instead, when encountering Greens) usually has a signal restricted to make it incapable of showing a green aspect until fixed. (This is so it effectively ‘tells the truth’ and doesn’t result in multiple drivers reporting the same fault as you don’t need to specially stop to report it, only at the first opportunity to do do,( i.e not on the move)
 

krus_aragon

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Signal LJ68, on the Up Main at Conwy, is a one-aspect signal: it can only show red!

The Up Main is bidirectional between Llandudno Junction and Conwy, and LJ68, just beyond Conwy station, marks the limit. Back when Conwy Valley services interworked with Holyhead stoppers, there used to be some occasional Llandudno-Conwy services too (e.g. one mid-morning shuttle in the 1994 timetable on my shelf). I've got no idea when it was last used, though.

Doesn't satisfy the OP criteria (as it doesn't actually have a green aspect), but for reference these "fixed red" signals generally are used at the end of a stretch of bi directional running where a reversal is required. They stop the driver from continuing on down stretch of track that is no longer signalled for bi-directional running.

Forgive the thread resurrection, but this morning I found myself staring at LJ68 as I passed it, and noticed that it has two lamp positions on the signal head, not just the one. Whether a green or yellow bulb was ever fitted to it is another matter!
 

sw1ller

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Forgive the thread resurrection, but this morning I found myself staring at LJ68 as I passed it, and noticed that it has two lamp positions on the signal head, not just the one. Whether a green or yellow bulb was ever fitted to it is another matter!
Everything I can find about it either in my training notes and online, suggests it’s a one aspect signal only capable of showing red. It does have the two lenses but I would hazard a guess that this was installed for future preparation to extend the bi-di running (which has obviously never happened). Either that, or they had spare two aspect signal heads lying around at the time of installation and couldn’t get hold of any one aspect units.
As has been mentioned, there’s nothing for it to be signalled to. You could argue it could clear to a yellow to get you to PR16 ground position signal. But that’s a stretch. And either way, it doesn’t meet the OPs parameters.
 

4-SUB 4732

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The signal that protects Shepreth Branch Jn approaching from Cambridge cannot show green for a train diverging towards Royston, even if the next signal is green. The least restrictive aspect it can show for this direction is Double Yellow.

That's a good one. Coming down with the double yellow, yellow and cruising round the corner at ~50 hoping it would clear with the route indicator... Else you'd be in trouble!
 

Tomnick

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Everything I can find about it either in my training notes and online, suggests it’s a one aspect signal only capable of showing red. It does have the two lenses but I would hazard a guess that this was installed for future preparation to extend the bi-di running (which has obviously never happened). Either that, or they had spare two aspect signal heads lying around at the time of installation and couldn’t get hold of any one aspect units.
As has been mentioned, there’s nothing for it to be signalled to. You could argue it could clear to a yellow to get you to PR16 ground position signal. But that’s a stretch. And either way, it doesn’t meet the OPs parameters.
It can’t even be that - you can’t have a main aspect reading to a shunt signal. I’d say that it’s probably one of the two things that you suggest - probably the latter!
 

Islineclear3_1

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When trains used to go into Newhaven Marine, the platform signal at the Harbour never displayed a green aspect. It was always orange with the junction feather illuminated.

Trains signalled onto the Seaford branch however, got a green aspect
 

edwin_m

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When trains used to go into Newhaven Marine, the platform signal at the Harbour never displayed a green aspect. It was always orange with the junction feather illuminated.

Trains signalled onto the Seaford branch however, got a green aspect
A signal cleared for a route that ends in a buffer stop will only show yellow (which is never referred to as orange or amber). This has been true since the 1974 Moorgate collision, it was never really explained why the train went at full speed through the station into a dead-end tunnel, but one result was concern about drivers being misled by green signals on the approaches to termini or bay platforms.
 

Belperpete

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Are there any signals on the network that for some reason cannot show green (not including signals that don't actually have a green aspect, obviously)? As in signals that technically are capable of showing a green aspect but never do in real life.
In theory, there shouldn't be any.

If the interlocking has been configured so that the signal can never display a green aspect, then with traditional filament-bulb signal heads, the signal shouldn't have been provided with a green aspect. At one time, such a signal would have been provided with a special head, e.g. a head with just red and yellow aspects, but latterly (to save the cost of stocking rarely-used heads) it became practice to use a standard head. However, in such cases, not only will the green aspect not be wired up, but the green aspect should also be blanked out, to prevent any possibility of a phantom green aspect. Such a signal might look as though it can display green, but it can't.

With modern LED heads, again a standard 3-aspect LED head may be used in such cases, with the green aspect just not wired up. There is no need to blank the green LED aspect off, and indeed there is no way of doing so without blanking off all the other aspects too. However, how could you tell whether an LED signal has an unused green aspect or not without examining the innards of the head?

Signals that physically have a green aspect, but are prevented from showing it (e.g. by the green aspect being blanked off and/or not being wiring up) surely don't count as "signals that are technically capable of showing a green aspect". In which case, as I stated earlier, there shouldn't be any. The only exception I can think of, would be in cases where it was intended to commission the green aspect at a later stage.

There are probably quite a few signals that can show a green aspect, but in practice never do (e.g. signals that read in or out of no-longer used lines, and such like), but that is a different topic - the OP asked about signals that cannot show green despite having a working green aspect.
 
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I would imagine there are a good many.
Consider a signal in rear of a signal with approach release for instance.
The signal isnt cleared until the track circuit has been ocupied for a given length of time, so the signal in rear of it will never show green, only ever yellow, but it will have the capacity to show green.
 

LUYMun

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Of course this doesn't count but at Beaulieu Road, the down signal (towards Weymouth) is a signal that only shows green and yellow, but never red.
 

krus_aragon

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Everything I can find about it either in my training notes and online, suggests it’s a one aspect signal only capable of showing red. It does have the two lenses but I would hazard a guess that this was installed for future preparation to extend the bi-di running (which has obviously never happened). Either that, or they had spare two aspect signal heads lying around at the time of installation and couldn’t get hold of any one aspect units.
As has been mentioned, there’s nothing for it to be signalled to. You could argue it could clear to a yellow to get you to PR16 ground position signal. But that’s a stretch. And either way, it doesn’t meet the OPs parameters.
Thank for having a dig about for me. I don't doubt that it only shows red aspects, but the pair of lenses caught my attention yesterday. I too had been wondering if it was a case of installing whatever was to hand at the time.
 

rower40

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E510 and E512 at the east end of Haymarket never seemed to get beyond a double yellow but were capable of displaying greens.
ARS on Edinburgh doesn't set route over Princes Street Gardens for a train stopping at Haymarket, until that train has left Haymarket station. So all stopping trains will never get better than double-yellow on those signals - unless the signaller intervenes to set route "early" over Princes Street Gardens. Non-stop (possibly ECS) trains might get a green there, but there'd have to be nothing needing to use the crossovers at Princes Street Gardens at the same time.

Another location where signals could show green but never do: on the SIMBIDS sections between Shenfield and Marks Tey, there are several crossovers, where trains can switch from right-road (up along up line, or down along down line) to wrong road (up along down line, or down along up line). In "right-road" running, there are many 4-aspect signals between each crossover. When running "wrong-road", there is a signal protecting the crossover, and it has two repeaters - the first showing double-yellow or green, and the second showing single-yellow or green. These repeaters will only ever show green if a train running wrong-road has a route set to remain wrong-road - i.e. not to revert to "right-road" at that crossover. Because if the route is set for the train to revert to "right-road", the wrong-road signal protecting the crossover is approach-controlled-from-red, so its repeaters show double-yellow and single-yellow. And the timetable is so busy that, even on a Sunday, there isn't enough time for a train to use two consecutive wrong-road sections.

I expect the same is true of the bidirectional sections between Didcot and Swindon.
 

TheEdge

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CO328 at Ipswich is able to but rarely does show a green, most trains passing it are terminating in Platform 1 with is a bay. Even when you pass it going into 2 it normally still doesn't give you a green.
 

swt_passenger

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Could that by any chance be the colour light version of a Distant signal?
Yes, it’s a two aspect area once west of Totton, with long signal sections with distants and the ensuing long headways. Not really relevant to the topic under discussion, I’d have thought.
 
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Speed43125

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DB 42 at Dunblane, as it really only ever clears trains from platform 3 on to the headshunt (otherwise known as the down line). Used to be common for goods to use it as a passing loop, and occasionally when the VTEC HST was late that would use it too, but that seems to have stopped since the last timetable change (more frequent terminating trains).

Best story I have is when a 365 occupied the down platform 2, and an HST on crew training had to use the extra loop (at the 15 limit) to pass it and continue north.
 
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