Crossing signals

[Buz]

Hi all

I have while trying to get grips with what makes a railway Irish ,come across pictures of twin armed semaphore signals that appear to be guarding level crossings.

How common was this and how are they operated  they never seem to show a operating lever or signal wire in the picture, also are they co acting arms ie both move together showing same position.

Are they painted different colors to standard signals.

regards John

Edited August 31, 2020 by Buz

[David Holman]

The Sligo had a three armed signal to control the same number of adjacent level crossings. Copied it to use on my Arigna/Belmullet project. Will try to post a picture later.

[Irishswissernie]

This one ?     1956-05-16 SLNCR  Thornhill No 9 Gatehouse signal protecting 8,9 & 10 crossings. JGD orig173

 

[Buz]

Hi Irishswissernie

I thought slotted posts got banned after a tragic 19th century rail disaster in England arm froze in the off position due to winter snow.

Not co acting then?? or are they that has two arms off I did not think that was possible because of interlocking?? that looks weird.

Black white and? the colors on the back of the bracket signal.

Take the bracket off and change it to std semaphore lower quad arms and you have more or less the signal I am asking about that seems to show up at several level crossings some times with an odd arm shaped like a hockey stick and a spectacle plate in or near the center of the arm and some times two std arms

regards John

 

[Galteemore]

Bog Road, Cork. This what you’re after ? Interlocking is unlikely on the SLNC ones as they are in the middle of a block section anyway. Their slotted posts did last till 1957. SLNC signalling was arcane but effective! 

[Buz]

7 minutes ago, Galteemore said:

Bog Road, Cork. This what you’re after ? Interlocking is unlikely on the SLNC ones as they are in the middle of a block section anyway. Their slotted posts did last till 1957. SLNC signalling was arcane but effective! 

That's the kind of thing have seen pictures with that kind of thing from a couple of locations can never find anything that explains what it is and how it works and its indications.

It seems from pictures I have found both arms read the same or do they??, but nothing clear on its colors.

I am guessing it guards the level crossing.

regards John

[Galteemore]

Almost certainly worked by the crossing keeper themselves. Day glo orange on both arms by CIE period. The arms are the same both sides 

[murphaph]

Are these just a "repeater" for the X on the gates? Are the X's the actual signal or how does it normally work?

[Galteemore]

The x is probably aimed more at road traffic when swung across the carriageway. The signal is an indicator to the oncoming train that the crossing keeper has closed the gates in a timely manner ! 

[Buz]

7 minutes ago, Galteemore said:

14 minutes ago, murphaph said:

Are these just a "repeater" for the X on the gates? Are the X's the actual signal or how does it normally work?

The x is probably aimed more at road traffic when swung across the carriageway. The signal is an indicator to the oncoming train that the crossing keeper has closed the gates in a timely manner ! 

I know in the UK the big red spot or diamond on the gates depending on railway acted as a stop signal for the train if the gates where still open.Not sure the X is big enough for a signal.

 

This suggests the twin arms should both be in the same position depending on gates open or closed which would be relatively simple to do.

regards John

[murphaph]

The X is the "target" whatever that means. Sounds like a signal to me. Otherwise it's the red lamp on the gate I suppose:

http://www.railsigns.uk/overseas/ireland3/ireland3.html

[Mayner]

The signalling of manned level crossings was largely dependent on local conditions in particular whether the driver of a train could see a signal or gate in time to safely stop short of the crossing!

On passenger running lines crossings were normally protected by a working distant signal, the crossing barrier or gate was normally classed as a home or stop signal although separate home signals were usually provided where there was poor sighting as a result of a curving approach or a crest between the distant signal and crossing gates. 

In some cases signals were operated without a lever frame by physically opening or closing the crossing gate, a lever frame interlocked with the gates was usually required on crossings with working home and distant signals such as those between Liffey Junction and Maynooth on the Midland main line

Crossing signals were normally fixed at danger at un-manned crossings on goods only or lines with no regular passenger service like Drogheda-Kingscourt.

A lot of crossing signals were based on steam stopping distances and had to be moved out with increasing train weight and freer running rolling stock, there was an incident in recent years where a Liner ran through a set of gates on the Mayo Line despite the driver applying the brakes as he passed a distant signal at danger. 

Signals where the arm slotted vertically within the post to display a clear aspect were phased out following the Abbots Ripton disaster where a signal arm in the 19th Century, but continued in use in the North East of England into the British Railways Era, the SLNCR no doubt continued with it antique signalling because it worked and did not have the money or see the need to modernise.

[David Holman]

19 hours ago, Irishswissernie said:

This one ?     1956-05-16 SLNCR  Thornhill No 9 Gatehouse signal protecting 8,9 & 10 crossings. JGD orig173

 

That's the one. Notice the spectacle plate lower down the post. It showed a clear white light to proceed I believe.

[Buz]

22 hours ago, David Holman said:

That's the one. Notice the spectacle plate lower down the post. It showed a clear white light to proceed I believe.

Looking at the picture and it being a very very obsolete type of signal by 1958 it is quite possible that it does show a white light for proceed.

Although one would hope by that year they had found a way for it to show a green light for proceed as per the standards well and truly in by then.

But that depends on is it an indicator or a signal if it is classed as an indicator, Not a signal then they can get away with the white light and a notation in the general appendix to the book of rules or its equivalent.

Not sure what year the colours changed from Red, Green and White to the Red, Yellow and Green for lights we recognize today but it was quite early on in the signals story.

regards John