One for the Signalling Nerds

[Junctionmad]

I recently completed a comprehensive survey of Claremorris station buildings

 

heres one for the signalling nerds, This is my shot of the signal diagram, which was restored to represent the " original " when the box was closed, it should be high res ,

 

Interesting that " original " is not actually original , and only represents the box around the 80s. the O'Dea Collection shows the diagram when the Ballinrobe branch was in operation , and the box was completely utilised.

 

Also many signals had been reduced to ground signals as well

 

Anyway Heres my questions

 

(a) What do the colours of the track diagram represent , i.e. the blues, greens etc

 

(b) I couldn't ascertain this on the day but I presume ALL the red sections are track circuit bulbs, in various pictures Ive seen some were lit up.

The question here is they seem to be in pairs , i.e. both light in the colour band would be illuminated , except where there is only one red band in a section colour ( if you get me) I presume the little number in between the track circuit bulbs is the circuit number .

 

© Certain ground signals are paired , i.e. have a look at 60A and 60B to the west of the box. There is only one lever in the farm , i.e. 60, , clearly 60B is associated with the catch point, but is it associated with level 60 ?? Similar with 50 A and 50 B, at the east end. Is it that they just alternative as the lever is reversed in the frame

 

(d) The point near the Turntable is marked H.P. it used to be controlled by lever 31.

 

(e) Note the fouling bars on 29 and 24, it must be that these never got track circuits maybe because they were so close

 

(f) interesting while the goods sidings are shows, there is an additional track parallel to the turntable , which is left out on ALL signalling diagrams including the one from the 60s !! , I wonder why

 

(g) Note signal 7 ( near the goods yard entrance) was a calling on signal , ( which were rare in Ireland ) , I presume this was to facilitate running an engine back again an occupied train standing in the platform, AM I right here, what operations on this station would it have been used for

 

(h) several signals have the suffix A.R, which I though might be Automatic repeater , since the block instruments are gone, I presume this meant there was repeater indicators in the signal box Thes were added between 1960 and 80.

 

(i) Whats does the shadow signal symbol on some of the AR signals 62 , etc mean ( i.e. the white semaphore in the off position )

 

Note interesting that Claremorris had several yellow ground disks ( ie could be passed at danger), anyone know the rules as to when such ground signals could be passed.

 

I just love this junction , its a signalling mecca ( well it was sniff sniff)

 

 

Edited March 27, 2015 by Junctionmad

[Junctionmad]

Come on. There must be some experts out there

[jhb171achill]

I'm afraid I'd be lost in the signalman's world..... the one thing I remember from many an hour in many a mechanical signalbox is that the levers were colour coded - yellow for a distant, red, for a home, white for a spare, black for a set of points. I can't remember what blue was, and I'm pretty sure the aforementioned were the only colours. I've a dim recollection of seeing a lever somewhere which was white with a red band round it, but I couldn't be sure.

 

Maybe these colour codings had some relevance to colours on a track plan. I don't know....

[snapper]

Don't suppose you have pictures of the levers with the actual notes on the faceplate?

 

Signal lever colour codes

 

Red = Stop signal

Green = Distant signals

Black=points

Blue=locking bars

Blue/black=points and locking bar combined

Black/red=ground frame release

black/red/black= CTC slot

yellow=wicket gate locks

Brown= Level crossing lock

White=spare

[snapper]

(A) if I remember correctly the different colours mark the start and end of the different track circuits.

(B) Not quite sure what you mean

©It is possible that these signals used a 3 position lever, when the lever is half way in the frame the signal is at danger, pushing or pulling the lever will alter different signals depending on how the points are set.

(D) H.P. most likely denotes hand points

(E) I would think that all of the area in green around 29/24 would be the one TC

(F) No idea

(G)Services used to arrive from Ballina, run round and head bak before Manulla junction was reinstated. might also be useful for joining or splitting services.

(H) No idea on that one

(I)means they are slotted, i.e. the signal can only clear if the level crossing and the signal box both clear the signal.

(J) I think you could pass the yellow disk at danger when the points were in the normal position, usually something like you could move into the headshut at danger but needed the disk to clear if you wanted to go onto the main line.

[jhb171achill]

My recollections were (mainly) from former GNR cabins. Is it possible they had yellow for distants? Or maybe the UTA did?

Edited March 28, 2015 by jhb171achill

[snapper]

My recollections were (mainly) from former GNR cabins. Is it possible they had yellow for distants? Or maybe the UTA did?

 

Very possible, the list I gave above was from an article about Irish Rail signaling practices.

[snapper]

Some pictures and details here about Castlerock showing yellow for the distant signals

 

http://www.signalbox.org/overseas/ireland/castlerock.htm

[jhb171achill]

Green could be a modern thing. In childhood / adolescent hood, I was in signal boxes in Lisburn, Portadown, Kildare, Athy, Bagenalstown, Waterford (need a head for heights!), Kilmacthomas, Enniscorthy, Limerick Jct., Westport, Portrush, Ardee, Foynes, Moate.....etc etc.... and I don't recall ever seeing a green lever anywhere.....

[snapper]

I think they are a kind of a rarity, there seems to be a lot of fixed distant out there which would have no lever. I did a little research this evening and I found a few examples of green (there may be lots more) Glounthaune, Newrath LC and Adare. I have not seen any yellows in IR.

[Mayner]

Claremorris was probably the last major mechanical re-signalling scheme carried out by the GSR when the new Central Cabin was opened in the 1940s. The Central cabin replaced the East & West Junction Cabins (or was it North & South), the Ballinrobe Branch Cabin and Yard Ground Frame.

 

Further alterations were carried out in the 1950s when the loco shed between the down mainline and Ballinrobe branch platforms was demolished and the loco shed road extended to connect with the Tuam Line. This allowed trains to or from the Tuam direction to run into the new Platform 3 while the two Mayo Line platforms were occupied.

 

The early 50s alterations appear to have used up all the spare levers in the frame resulting in the use of 'economical" point locks on the crossovers opposite the signal cabin and the paired arrangements for operating some of the ground signals.

 

The signals marked AR were most likely fitted with a repeater to indicate whether the signal lamp was working or not. The signals marked AR controlled exit and entry from the single line sections and it would have been difficult if not impossible for the signalman to observe the state of the lamps from the cabin, given the considerable distance of the signals from the cabin and the way the main line curves away at the East & West ends of the layout.

 

Up to the Manulla collision in the early 1960s "calling-on" arms were fitted to home signals (mother and child signal) to control movements into a station when the Main Line into the next section was blocked and the Home signal at danger. If the station was blocked the (mother) signal was held at danger and the calling on arm (child signal) only lowered when an approaching train came to a complete stop.

 

An AEC railcar set was blocked outside of Manulla as a C Class shunted the Night Mail. The signal man forgot to return the "calling on arm" to danger after a shut, seeing the calling-on arm in the off position the driver of the passenger ran into the loop and collided with the mail.

 

The rule book was re-written after the accident and the 'calling on arms" on CIE re-designated "loop homes", the home signal reading to the main-line. This was ok at stations where bracket signals were at equal height but could be confusing to a driver if the loop was on the right hand side of the running line

[Junctionmad]

The signalbox.org forum answered my questions on everything bit the calling on

 

Mayner could you expand on what you meant in that regard. Are you saying that cie stopped using calling on signals and re designated them as something else , are you saying that specific signal now controlled running into a loop , rather then allowing movement into a occupied section.

 

I always understood callin on , like what was used to release locomotives at Hueston , once the pilot had removed the train. I don't believe it was used to signal blocking back into an occupied section

 

The linked signal 60 A/B was set according to the route set. Ie the lever was effectively reused to control two different signals depending on other levers. The plate on lever 60 reads 29 or 28 24 or Nil , so I read that that one ground disk was activated by lever 60 , if 29 or 29 were reversed , or of 24 was reversed , then 60 B. Nil presumably meaning 60B was activated if none of the previously conditions were met.

 

I only assume A refers to the first line and B to the second line on the plate

 

Claremorris had 4 boxes and a ground frane. , the north box is still there at the head of the goods sidings

 

I'm abandoning my limerick junction plan and working up a layout based on claremorris with all junctions working passagner service into the 90 s ! So I have to re signal it for passagner working and I'm basing this on 60 s signalling diagram, never if in real life passanger services had ceased well by then

Edited March 29, 2015 by Junctionmad

[Mayner]

Junction Mad

 

 

Calling on arms on the CIE system were re-designated "Loop Homes" following the Manulla collision in the early 1960s.

 

My understanding is a loop home was intended to allow a train to enter a loop without stopping at the home signal, while with a calling on arm the train was required to stop at the home signal before the calling on arm could be lowered.

 

The change in designation may also have been tied up with the conversion of crossing places on several lines from conventional Up & Down to bi-directional working in a similar manner to the ex-MGWR main line with a main running road and a loop.

 

The RAIU a reliable source of information on CIE signalling practice and an insight on what sometimes happened in practice. http://www.raiu.ie/publications/ The report on the 1979 Arklow & Rosslare Strand collision reports make interesting contrast between custom and practice and regulation.

 

The report into the 1955 Cahir beet train derailment is particularly interesting the station was signalled for traditional up and down working with left hand running through the platform roads rather than reversible working.

 

The road was set for the ill fated Up beet train to run onto the Down platform road and through the stoppers into the river, as the Down Mail was blocking the up platform road taking water from the column at the Limerick end of the Station

[Junctionmad]

Sorry john. Do you mean that the calling on was used to signal a route into a bi directional loop, ie almost as if the signal was on a bracket

 

Rather then the standard callin on , that pointed to the same road as the home above it.

 

Since signal 7 the calling on. In claremorris is past any crossover. I'm not sure how it would be used as anything else other then calling on

Edited March 30, 2015 by Junctionmad