Talk:Railway signal

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To-do list for Railway signal: edit · history · watch · refresh · Updated 2007-06-04 Images of dwarf, position and color position signals Copyedit References Review/augment non-USA discussion Historical section (e.g. ball and banjo signals)

I've never seen a British signal, and the article makes me quite curious. Pictures would be great. Stargoat 20:10, 1 Sep 2004 (UTC)

According to other online sources and information out there, this African-American inventor was the one who invented the railroad semaphore in 1906 not that James fellow. I believe this page along with many others needs some dire re-visioning soon. Once again, African Americans who have contributed something to U.S society is left out again.

source: http://www.blackinventor.com/pages/richardspikes.html —Preceding unsigned comment added by Dew3 (talk • contribs) 20:49, 26 February 2008 (UTC)[reply]

Railway semaphores existed long before 1906 - the one invented by Mr Spikes must have been one of many variants on the original concepts - further research would be required on what exactly, the link isn't specific enough. Wongm (talk) 22:24, 26 February 2008 (UTC)[reply]

One can see an illustration from 1888 of a semaphore here. I did a google patent search on Spikes, and while plenty of other stuff that he invented shows up, there's no patent for a railroad signal, no matter what the year. As far as I can tell, this claim is puffery. Mangoe (talk) 22:27, 26 February 2008 (UTC)[reply]

Would be nice to have some info about RR signalling in the US. Topics might include searchlights/color position light signals, and the absolute permissive block system. --ZekeMacNeil 23:41, 23 Dec 2004 (UTC)

It's nearly completely content-free right now, but I've started a North American railway signaling stub. A similar article, using the British spelling signalling also links there. Someone (maybe me, maybe you) can fill it with content along the lines of the articles already out there on similar national/regional practices:

• Australian railway signalling
• German railway signalling
• Norwegian railway signalling
• UK railway signalling

— JonRoma 06:37, 6 February 2006 (UTC)[reply]

I just completely rewrote the section at Railway signalling#Signaling in the U.S.. It might contain a little bit of what you're looking for, although you seem to be looking more for info on the actual signals themselves (style, aspects, method of operation, etc.), which I'm less familiar with (though I know a signal maintainer who would know all of that stuff). Try looking at the following resources for some leads, too:

• Railway Signalling and Operations FAQ
• North American Signaling

cluth 04:26, 17 August 2006 (UTC)[reply]

There is significant overlap of content and subject matter in Railway signal and Railway signalling and I propose the content from Railway signal be merged to Railway signalling, which is a more appropriately-named article.

• Support. — JonRoma 21:26, 4 February 2006 (UTC)[reply]

• Support. — John 22:16, 4 February 2006 (UTC)[reply]

• Oppose - Please note that this proposal was already discussed at Talk:Railway signalling and rejected. --Qualle (talk) 10:45, 5 February 2006 (UTC)[reply]

I sure don't see a formal proposal or consensus from that discussion (in November 2005). Anyone is entitled to their opinion, of course, but I fail to see the value of two distinct articles that treat nearly the same subject matter. Both treat the fundamental subject of signalling practice rather than one discussing signaling devices and the other discussing the philosophy behind signalling. Perhaps someone can explain the benefit of having such similar material divided between two articles. Regards. — JonRoma 06:19, 6 February 2006 (UTC)[reply]

• Oppose - G-Man * 20:06, 5 February 2006 (UTC)[reply]

• Oppose — Railway signalling should be about all the operations to do with railway signalling, and Railway signal should be about the signals themselves. Ae-a 12:57, 31 May 2006 (UTC)[reply]

• Oppose A Signal, and Signalling are two differing topics

• Oppose There is too much to discuss about signalling as it is without merging the "signal" article in. Mangoe 04:06, 28 June 2006 (UTC)[reply]

I've taken out the RfM as there is no reference on the RfM page, this has sat around for months, and I've expanded the article drastically since the proposal was made. Mangoe 14:42, 4 July 2006 (UTC)[reply]

• Support I support the merge because the topics are nearly identical; however, I have no position as to the "direction" of the merge, as both articles are potentially of GA quality. 69.140.164.142 03:25, 6 April 2007 (UTC)[reply]

I've almost totally rewritten this article, partly to filter out the general signalling discussion, but mostly to discuss the great variation in North American practice. At this point I don't think there's cause to merge this into railway signalling anymore.

As I've made such extensive changes, the article needs considerable review. See the "tasks" list for more info. Mangoe 19:22, 28 June 2006 (UTC)[reply]

I have posted my thoughts on the organisation and coverage of signals and signalling articles in Talk:Railway signalling#Safeworking/signalling topic organisation. Philip J. Rayment 11:22, 18 September 2006 (UTC)[reply]

This part seems extremely dubious. At least in US practice there is important detail about batteries and such. The variation in line current supply is really of no importance. Mangoe (talk) 22:55, 27 December 2007 (UTC)[reply]

Signalling power supplies is a topic for the Railway signalling article, not this one. I'm struggling to find any of this worth keeping here. Signalhead (talk) 23:07, 27 December 2007 (UTC)[reply]

The following paragraph from the article -

"Furthermore, the Long Island Rail Road adopted position lights after it was bought outright by the PRR. After the Penn Central merger, the former all-amber position lights were modified with twin red lenses in the upper horizontal position for enhanced recognizability of Stop signals at interlockings."

- is incorrect from what I've seen. I have never noted twin red lenses above any amber position lights, and I've been riding the LIRR for years (and paying attention to such things). The LIRR's use of all-amber position lights is correct, however, although I can't speak to the history of when and why they were adopted.

I'd be interested to see if someone could confirm my assertion before I go and edit the article.

-_Scott

BTW - I'm writing this message whilst on my way home from work on an LIRR train. —Preceding unsigned comment added by Scott.m.rosenberg (talk • contribs) 00:08, 2 April 2008 (UTC)[reply]

I've undone some recent changes, and particular checking reveals that "gantry" and "signal bridge" are essentially synonyms. Mangoe (talk) 20:52, 24 April 2008 (UTC)[reply]

One might mention that whereas a signal bridge has two posts, a bracketed signal has just one. Tabletop (talk) 23:32, 27 January 2009 (UTC)[reply]

Signal aspects on different railways are more easy or less easy to protect against lamp failure.

Considers the single green and double green on German, Danish and Swedish Railways.

In Sweden (or is it Denmark) the more green lights the higher the speed, so if a green lamp fails, this automatically leads to a lower speed aspect, which is failsafe.

In Germany and Denmark (or is it Sweden) the more green lights, the SLOWER the speed, so that the failure of a green light is NOT failsafe. It is not clear how one might arrange the wiring to ensure safety.

In Germany, before 1948, single green meant fast, while double green meant slow. Post 1948, they changed the double green meaning a slow speed to a green over yellow, so that failure of the green light is not really a problem. Failure of the yellow light is still unsafe, however that yellow light can be proved to be alight before the green is lit.

The German, Danish and Swedish aspects are contradictory, so that traindrivers may have confusing problems if they cross the border.

Tabletop (talk) 05:29, 27 January 2009 (UTC)[reply]

Just wanted to say thanks to both for the improvements following my 'fact' tagging. Comparison of the today's text against yesterday's (unmodified) will show just how inadequate the latter was at explaining the issue!

The above text concerning international variants suggests that further work is still required for a complete explanation.

EdJogg (talk) 12:59, 27 January 2009 (UTC)[reply]

I came to this article trying to decode a common sign I see on CN railways, two white diamonds side-by-side on a black background on an oval plate. This article covers only signals that can change, and I don't see any for fixed signage. Can someone point me in the right direction? Maury Markowitz (talk) 11:57, 1 June 2009 (UTC)[reply]

An image used in this article, File:CSX color position light Savage MD.jpg, has been nominated for speedy deletion for the following reason: All Wikipedia files with unknown copyright status What should I do? Don't panic; you should have time to contest the deletion (although please review deletion guidelines before doing so). The best way to contest this form of deletion is by posting on the image talk page. If the image is non-free then you may need to provide a fair use rationale If the image isn't freely licensed and there is no fair use rationale, then it cannot be uploaded or used. If the image has already been deleted you may want to try Deletion Review This notification is provided by a Bot --CommonsNotificationBot (talk) 13:53, 15 November 2011 (UTC)[reply]

The right edge of this article is overrun by a series of images which tend not to correspond to the paragraphs they go with. Can we do something about this? Mangoe (talk) 21:52, 20 November 2015 (UTC)[reply]

This is certainly something that must be explained. --User:Haraldmmueller 15:00, 19 December 2015 (UTC)[reply]

I believe that the intention is to discussion the theory of signalling at the article railway signalling (see railway signalling#Route signalling and speed signalling), and the physical hardware and signals themselves in this article (railway signal)—though obviously there will necessarily be some overlap between the two articles. TenOfAllTrades(talk) 15:27, 19 December 2015 (UTC)[reply]

That sounds reasonable. However, indicating that, in contrast to signals for speed signalling, signals for route signalling do not need more than one indication (but maybe route indicators); and give an explicit link to railway signalling#Route signalling and speed signalling would be nice. Maybe I'll add a sentence or two ... --User:Haraldmmueller 15:35, 19 December 2015 (UTC)[reply]

Definitely! TenOfAllTrades(talk) 02:17, 20 December 2015 (UTC)[reply]

The above sentence (in "Mechanical signals") is

1. unclear or misleading: Of course they are always cleared by the signalman. What the sentence wants to say is, probably, that the wire for clearing the signal is pulled (and not released) to prevent a clear signal in case of a failure. If this is the intended meaning, it should say so, especially without using quotes;
2. wrong, as can be seen at Italian semaphores, where the signal wire is (was) released - see this picture of a signal lever and this picture of the corresponding wire extension compensator (both taken in 1990), which reverses the direction of the wire travel - so, actually, part of the wire is released (the third between the lever and the compensator), whereas two thirds are pulled (the two thirds from the compensator to the signal). A "mechanical failure" between the lever and the compensator will, therefore, clear the signal. I do not know why the Italians accepted that possibility (but the English accepted other possible problems, which e.g. the Austrians did not accept, which led them to the introduction of the "Drahtnachzughebel" or "wire pulling levers" ... which I will explain here later).

--User:Haraldmmueller 08:24, 14 September 2018 (UTC)[reply]

The articles are merely collection of information from various sources and presenting them in a form of article. While reading all articles relating to railway working like single line working, railway platforms or railway signals i found they are full of errors and give misleading information. This is because they are written by people who are not through enough in the subject. Its like person who is not a surgeon and writing about patient's operation. The articles are landing nowhere. Worst of all if a knowledgeable person tries to point out errors he is not welcomed and person controlling it are rude in communicating and reluctant to changes by giving illogical replies.If you are unable to communicate properly or convince others properly what you expect from others? So why should we contrbute? Just for social cause but that ends in bad reply from your side. Then why to waste the valuable time of others? You can stick to your artcle which has body but no soul in it. After all its your artcle and not mine. Firozpur (talk) 15:49, 26 November 2018 (UTC)[reply]

Happy sulking - and yes, WP is a sort of social media, as also your outpour shows. --User:Haraldmmueller 18:39, 26 November 2018 (UTC)[reply]

Please see remarks of Wikipedia person on talk in single line working. Firozpur (talk) 14:57, 4 December 2018 (UTC)[reply]

Addittion made in talk in Application of Railway signal but not eddited not because of happy sulking but aatitude of WP Firozpur (talk) 15:01, 4 December 2018 (UTC)[reply]

This page is a bit of mess as of right now. As far as I can tell it should be specifically focusing on railroad signals themselves, not signaling as a whole. I removed a good bit of uncited incorrect information and some extraneous information about specific practices.

Writing about railroad signals can be quite hard because not only do practices vary by country, they vary by railroad and often within railroads. Try to avoid writing general statements because they are often not applicable to all railroad Interlocker (talk) 23:02, 19 July 2024 (UTC)[reply]

Wikipedia is an encyclopedia not a dictionary. Besides describing what railway signals are, we must also show what they do. This also means taking a worldwide view of the subject. The practices of one country might not apply to another. Railway signals originated in the United Kingdom, so you should also not alter British spellings to American. --Redrose64 🌹 (talk) 07:35, 20 July 2024 (UTC)[reply]

It’s fine to describe what they do, it that information should be correct. Making general statements is wrong. Specifying NORAC examples is fine but NORAC doesn’t cover all of the US. Also, the entire signal power section is incorrect (and uncited) Interlocker (talk) 17:09, 20 July 2024 (UTC)[reply]

I think Auto Matic Block Signalling Merge should be done as it would make sense to fall in this section as it has very little which makes it even possibley worth it own section. I Like The british Rail Class 483 (talk) 17:10, 3 December 2024 (UTC)[reply]