894:(B&O) in 1920 and was patented by L.F. Loree and F.P. Patenall. It is similar to the position light system with the central light removed and the resulting pairs of lights colored in correspondence to the angle they make: green for the vertical pair, amber for the right diagonal pair, and red for the horizontal pair. An additional pair, colored "lunar white", may be added on the other diagonal for restricting indications. Speed signalling is indicated not by additional signal heads, but by a system of white or amber "orbital" lights placed in one of six positions above and below the main head. The position above or below indicates the current speed, while the left-to-right position indicates the speed at the next signal (full, medium, or slow in both cases). Dwarf signals have the same aspects as full-sized signals. One of the advantages claimed for the system is that burned-out bulbs produce aspects which can be interpreted unambiguously as either the intended indication (for the main head) or as a more restrictive indication (for the orbitals—if only the central head is lit, the indication is either slow or restricting).
274:
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states of New South Wales, Victoria and South
Australia, as well as New Zealand, a permissive signal has the lower set of lights offset (usually to the right) from the upper lights; in Victoria and New Zealand, an absolute signal displaying a red or white "A" light is also treated as a permissive signal. Some types of signal display separate permissive and absolute stop aspects. In Germany, the rules which apply to the respective signal are indicated by a vertical plate on the signal's post (
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1107:. These can display signal indications through patterns of lights in the locomotive cab, or in simple systems merely produce an audible sound to warn the driver of a restrictive aspect. Occasionally, cab signals are used by themselves, but more commonly they are used to supplement signals placed at lineside. Cab signalling is particularly useful on
1029:, so that if one burns out, the other keeps the signal lit. A more complicated version of this, such as in the SL35 lamp, a filament changeover relay is fitted in series with the first filament, where if the first filament burns out, the relay drops and lights the second filament. This filament fail relay also activates an alarm in the signal box.
560:
1132:
in some parts of the world (and previously in many more locations, before the widespread adoption of electricity), batteries are the primary power source, as mains power may be unavailable at that location. In urban built-up areas, the trend is now to power signal equipment directly from mains power, with batteries only as backup.
686:. Pasley had invented a system of optical telegraphy through semaphores in 1822 for the British military, and appears to have suggested to Gregory the application of the semaphore to railway signaling. The semaphore was afterwards rapidly adopted as a fixed signal nearly universally. Disc signals, such as those made by the
555:
is the meaning. In
American practice the indications have conventional names, so that for instance "Medium Approach" means "Proceed at not exceeding medium speed; be prepared to stop at next signal". Different railroads historically assigned different meanings to the same aspect, so it is common as a
336:
Originally, signals displayed simple stop or proceed indications. As traffic density increased, this proved to be too limiting and refinements were added. One such refinement was the addition of distant signals on the approach to stop signals. The distant signal gave the driver warning that they were
960:
When multiple tracks are involved, or where space does not permit post mounting, other forms are found. In double track territory one may find two signals mounted side by side on a bracket which itself is mounted on a post. The left hand signal then controls the left-hand track, and the right signal
466:
Some signals convey large amounts of information. This older German signal indicates preliminary caution with max. 60 km/h in the upper main signal aspect (green above yellow, number plate "6") and caution in the lower distant aspect. The lower yellow number indicator announces a speed limit of
1131:
Usually, signals and other equipment (such as track circuits and level crossing equipment), are powered from a low voltage supply. The specific voltage varies with the country and equipment used. The reason behind this is that the low voltage allows easy operation from storage batteries and indeed,
575:
Signals control motion past the point at which the signal stands and into the next section of track. They may also convey information about the state of the next signal to be encountered. Signals are sometimes said to "protect" the points or switches, section of track, etc. that they are ahead of.
1040:
For example, in UK practice, if a white "feather" indicator fails, the low speed feather combined with a green light, which is low speed, becomes a green light on its own, which is high speed. A lamp proving relay would detect the reduction in current when more than two lamps are not working in a
819:
mechanism is used to move a coloured spectacle (or "roundel") in front of the lamp. In this manner, gravity (fail safe) returns the red roundel into the lamp's optical path. In effect, this mechanism is very similar to the colour light signal that is included in an electrically operated semaphore
606:
Drivers need to be aware of which signals are automatic. In current
British practice for example, automatic signals have a white rectangular plate with a black horizontal line across it. In US practice a permissive signal typically is indicated by the presence of a number plate. In the Australian
654:
The oldest forms of signal displays their different indications by a part of the signal being physically moved. The earliest types comprised a board that was either turned face-on and fully visible to the driver, or rotated away so as to be practically invisible. These signals had two or at most
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is one where the position of the lights, rather than their colour, determines the meaning. The aspect consists solely of a pattern of illuminated lights, which are all of the same colour. In many countries, small position light signals are used as shunting signals, while the main signals are of
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onward, searchlight signals have the disadvantage of having moving parts which may be deliberately tampered with. This had led to them becoming less common during the last fifteen to twenty years when vandalism began to render them vulnerable to false indications.
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Operating rules generally dictate that a dark signal be interpreted as giving the most restrictive indication it can display (generally "stop" or "stop and proceed"). Many colour light systems have circuitry to detect such failures in lamps or mechanism.
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Signals were originally controlled by levers situated at the signals, and later by levers grouped together and connected to the signal by wire cables, or pipes supported on rollers (US). Often these levers were placed in a special building, known as a
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is the portion of a colour light signal which displays the aspects. To display a larger number of indications, a single signal might have multiple signal heads. Some systems used a single head coupled with auxiliary lights to modify the basic aspect.
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result of mergers to find that different divisions of a modern railroad may have different rules governing the interpretation of signal aspects. For example, stop aspect refers to any signal aspect that does not allow the driver to pass the signal.
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For example, a flashing aspect can be used to display a less restrictive signal. In this case, if the relay that controls the flashing fails, the signal becomes more restricting. A flashing yellow, in Canada and the United States, is part of an
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Operating rules normally specify that a signal with an abnormality, such as one with an extinguished lamp or an entirely dark signal, must be interpreted as the most restrictive aspect – generally "Stop" or "Stop and
Proceed".
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is a visual display device that conveys instructions or provides warning of instructions regarding the driver's authority to proceed. The driver interprets the signal's indication and acts accordingly. Typically, a signal might inform the
518:
is installed, signals face in both directions on both tracks (sometimes known as 'reversible working' where lines are not normally used for bidirectional working). Signals are generally not provided for controlling movements within
1000:
systems commonly use only dwarf signals due to restricted space. In many systems, dwarf signals are only used to display 'restrictive' aspects such as low speed or shunt aspects, and do not normally indicate 'running' aspects.
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1443:
We have about 40,000 signals across the whole network, mostly colour light signals and with many benefitting from LED technology. There are also still some traditional mechanical semaphore signals.
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approaching a signal which might require a stop. This allowed for an overall increase in speed, since train drivers no longer had to drive at a speed within sighting distance of the stop signal.
849:
have started to be used in place of the incandescent lamps, reflectors and lenses. These use less power and have a purported working life of ten years, but this may not in reality be the case.
992:
In some situations or places, such as in tunnels, where there is insufficient room for a post or gantry, signals may be mounted at ground level. Such signals may be physically smaller (termed
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when the latter was under B&O control, as well as on the B&O itself. With the disappearance of the B&O into CSX they have been gradually replaced with NORAC color light signals.
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operation, the signals did not directly convey orders to the train crew. Instead, they directed the crew to pick up orders, possibly stopping to do so if the order warranted it.
603:('controlled') signals are typically absolute, while automatic signals (i.e. those controlled through track occupancy alone, not by a signalman) are usually permissive.
1111:. In the absence of lineside signals, fixed markers may be provided at those places where signals would otherwise exist, to mark the limit of a movement authority.
820:
signal, except that the omission of the semaphore arm allows the roundels to be miniaturized and enclosed in a weatherproof housing. Widely used in the U.S. from
658:
Semaphore signals were developed in France at the end of the 18th century, before being later adopted by the railways. The first railway semaphore was erected by
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where a train does not need to physically stop for a "Stop & Proceed" signal, but only decelerate to a speed slow enough to stop short of any obstructions.
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and colour-light signals at the beginning of the 20th century, which gradually displaced semaphores. A few remain in modern operations in the United
Kingdom.
1970:
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1608:
1960:
1905:
584:. When a train is waiting at a signal it is "in rear of" that signal and the danger being protected by the signal is "in advance of" the train and signal.
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which displays the arm or signal head at some height above the track, in order to allow it to be seen at a distance. The signal is normally placed on the
1037:
When lamps fail, this can result in aspects that are less restrictive (high speed) than when the lamps are correctly lit. This is potentially dangerous.
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Mechanical signals may be operated manually, connected to a lever in a signal-box, by electric motors, or hydraulically. The signals are designed to be
467:
30 km/h by displaying "3". At that specific station the selected route ends on a stub track, thus distant caution with additional speed limits.
2233:
1870:
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may also be used. This consists of a platform extending over the tracks; the signals are mounted on this platform over the tracks they control.
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In the U.S., semaphores were employed as train order signals, with the purpose of indicating to engineers whether they should stop to receive a
400:
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A dwarf CPL signal showing "stop". The three lamps above the main head allow "medium" and "slow" approach indications for the next signal.
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1945:
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Signals differ both in the manner in which they display aspects and in the manner in which they are mounted with respect to the track.
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to prevent the display of a signal contrary to the alignment of the switch points. Automatic traffic control systems added
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failed feather indicator, and prevent the green from showing. It can also display an indication on the signaller's panel.
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1935:
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made it possible to produce colour light signals which were bright enough to be seen during daylight, starting in 1904.
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railway is normally signalled in one direction only, with all signals facing the same direction on either line. Where
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786:. Hoods and shields are generally provided to shade the lights from sunlight which could cause false indications.
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The additional lights on
Japanese signal 10 show that the points are set for the left route at the next junction.
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1990:
1915:
1821:
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colour light form. Also, many tramway systems (such as the Metro of
Wolverhampton) use position light signals.
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219:
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so that if power is lost or a linkage is broken, the arm will move by gravity into the horizontal position.
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1980:
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signals, which display a "Stop & Proceed" aspect. Furthermore, a permissive signal may be marked as a
842:, they are still the standard colour light signal albeit with new installations being as outlined below.
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2453:
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This article is about physical railway signal devices. For the principle of railway signalling, see
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2020:
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690:, were sometimes used, but semaphores could be read at much longer distances. The invention of the
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to detect the presence of trains and alter signal aspects to reflect their presence or absence.
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1940:
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of the speed at which the train may safely proceed or it may instruct the driver to stop.
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1965:
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On the approach to a movable item of infrastructure, such as points or switches or a
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17:
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were the most often used signal type in the U.S. until recently. In these, a single
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A system combining aspects of the colour and position systems was developed on the
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2112:
1346:
1282:"US Railroad Signalling | The Railway Technical Website | PRC Rail Consulting Ltd"
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Lineside signals need to be mounted in proximity to the track which they control.
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in New York City, at the time a B&O subsidiary; they were also applied to the
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The term "ahead of" can be confusing, so official UK practice is to use the terms
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1455:
956:
A gantry of
British semaphore signals seen from the cab of a steam locomotive
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2509:
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2448:
2071:
706:
1364:
1119:
782:
type, with separate lights and lenses for each colour, in the manner of a
762:
West railway station, Romania. This type of signal is based on the German
299:
Two common types of signal. In both cases, the left signal shows "danger".
2600:
2418:
2157:
2081:
1045:
695:
591:
signals, which can display a "Stop" (or "Stop and Stay") indication, and
1637:
698:
and hence visible both by night and day, resulted in the development of
535:
A British lower-quadrant semaphore stop signal with subsidiary arm below
2102:
2005:
1081:(UK) or interlocking tower (US), and eventually they were mechanically
778:
Colour light signals come in two forms. The most prevalent form is the
571:. In the background, express train 81 is pulling away from the station.
500:
Ahead of platforms or other places that trains are likely to be stopped
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2682:
2107:
1955:
1925:
1643:
932:
When a single track is involved, the signal is normally mounted on a
897:
Colour position lights (CPLs) were first installed as a pilot on the
797:, with the lamp and reflector removed to expose the coloured roundels
648:
1328:
923:
combined main and dwarf signal mounted on a post, displaying "Stop"
510:'Running lines' are usually continuously signalled. Each line of a
1885:
1586:
1181:
Armstrong, John (1957). "All About
Signals" (Two-article series).
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816:
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That the line ahead is clear (free of any obstruction) or blocked
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2369:
1647:
1009:
Occasionally, a signal may be mounted to a structure such as a
587:
In North
American practice, a distinction must be made between
1025:
Electric lamps for railway signals are often fitted with twin
186:
84:
43:
1182:
1258:
Subset-023. "ERTMS/ETCS-Glossary of Terms and Abbreviations"
678:. Gregory's installation was inspected and approved for the
1044:
Due to this possibility, most signals are configured to be
731:(UK) two-aspect colour light railway signal set at 'danger'
670:, southeast London, in 1841. It was similar in form to the
347:
Signals are used to indicate one or more of the following:
716:
order, and also as simply one form of block signalling.
211:
30:
Not to be confused with the signals along roadways at
865:
PRR position light signal showing "Approach Medium"
563:
A Finnish distant signal at the western approach to
2833:
2751:
2646:
2492:
2404:
2252:
2201:
2095:
2059:
1861:
1830:
1797:
1749:
1681:
1609:"General Description and Location of Fixed Signals"
1056:indication, which means the second signal ahead is
115:. Unsourced material may be challenged and removed.
1640:– Worldwide railway signalling info and references
828:However, in some other countries, such as on the
1520:. Visual Communications Company. Archived from
1491:. Visual Communications Company. Archived from
1472:"US&S Searchlight Signal H and H2 Styles."
2381:
1659:
1514:"MBTA LED Signal Lights Saves $ 1.17 Million"
200:The examples and perspective in this article
8:
1971:Interoperable Communications Based Signaling
608:
551:is the visual appearance of the signal; the
1906:Automatic Train Protection (United Kingdom)
1459:Railways: History, Signalling, Engineering.
1395:Railways: History, Signalling, Engineering.
1261:. European Union Agency for Railways. 2014.
78:Learn how and when to remove these messages
2388:
2374:
2366:
1666:
1652:
1644:
793:Mechanism of a searchlight signal made by
27:Visual signal device for railway engineers
1198:Kichenside, G. and Williams, A., (1998),
1103:Some locomotives are equipped to display
354:That the driver has permission to proceed
256:Learn how and when to remove this message
238:Learn how and when to remove this message
175:Learn how and when to remove this message
1871:Advanced Civil Speed Enforcement System
1308:. Hutt Valley Signals. 29 December 2012
1248:
1064:, which means the next signal ahead is
396:
1544:"PENNSYLVANIA RAILROAD – SIGNAL RULES"
1392:"The Origin of the Railway Semaphore."
1193:"The Origin of the Railway Semaphore."
739:German railway signals showing aspect
406:Ball signal (USA, 1830) at "high ball"
318:Application and positioning of signals
2031:Train Protection & Warning System
1127:, typical of urban light rail signals
7:
1764:Integrated Electronic Control Centre
1580:"NORAC Operating Rules 10th Edition"
808:is used in each head, and either an
694:, which could be made brighter than
113:adding citations to reliable sources
2026:Train automatic stopping controller
1946:Continuous Automatic Warning System
1560:from the original on 7 October 2022
1306:"New Zealand Signal Classification"
1200:Two Centuries of Railway Signalling
674:then being replaced on land by the
1706:Communications-based train control
1542:Hoevet, Joseph (1 November 2010).
1327:Meyenberg, Wolfgang (2017-02-17).
25:
59:This article has multiple issues.
1072:Control and operation of signals
643:Mechanical semaphore signals at
447:
435:
423:
411:
399:
284:
272:
191:
89:
48:
2188:Westinghouse Brake & Signal
1951:Contrôle de vitesse par balises
1817:North American railroad signals
1153:North American railroad signals
1013:, bridge abutment, or overhead
385:are to be picked up by the crew
100:needs additional citations for
67:or discuss these issues on the
2046:Transmission balise-locomotive
2011:Sistema Controllo Marcia Treno
1921:Automatische treinbeïnvloeding
1807:Application of railway signals
1228:Signalling in the Age of Steam
418:British semaphore signal（1940）
375:The speed the train may travel
324:Application of railway signals
1:
1996:Punktförmige Zugbeeinflussung
1716:European Train Control System
1551:Railroad Signals Landing Page
747:The introduction of electric
430:Wood's crossbar signal (1830)
1936:Chinese Train Control System
1726:Radio Electronic Token Block
1347:"Semaphore | communications"
442:Revolving disc signal (1840)
378:The state of the next signal
369:in the US) are set correctly
1701:Centralized traffic control
892:Baltimore and Ohio Railroad
845:More recently, clusters of
488:In advance of other signals
279:Semaphore signals (Germany)
214:, discuss the issue on the
2907:
2596:Transfer table (traverser)
1901:Automatic train protection
1096:
903:Chicago and Alton Railroad
664:London and Croydon Railway
632:
321:
36:
29:
2584:ground-level power supply
2193:Westinghouse Rail Systems
2051:Transmission Voie-Machine
1896:Automatic train operation
1848:Track circuit interrupter
1696:Automatic block signaling
1691:Absolute block signalling
1286:www.railway-technical.com
1202:, Oxford Publishing Co.,
795:Union Switch & Signal
454:Double disc signal (1846)
342:timetable and train order
1991:Pulse code cab signaling
1916:Automatic Warning System
1822:Railway semaphore signal
1784:Solid State Interlocking
1518:Engineered LED Solutions
1489:Engineered LED Solutions
1168:Train speed optimization
961:the right-hand track. A
666:(later the Brighton) at
635:Railway semaphore signal
527:Aspects and indications
516:bidirectional signalling
372:Which way points are set
2569:Railway electrification
1891:Automatic train control
1351:Encyclopedia Britannica
1163:Train protection system
1060:. A solid yellow means
878:Colour-position signals
806:incandescent light bulb
471:Signals can be placed:
2067:Level crossing signals
1986:Positive Train Control
1981:Linienzugbeeinflussung
1711:Direct traffic control
1456:"Train Order Signals."
1128:
989:
957:
944:'s side of the track.
924:
887:
866:
857:Position light signals
798:
767:
744:
732:
700:position light signals
660:Charles Hutton Gregory
651:
609:
572:
567:station is displaying
536:
497:At a switch or turnout
468:
333:
2708:Platform screen doors
1789:Westlock Interlocking
1779:Rail operating centre
1741:Train order operation
1736:Track Warrant Control
1470:Railway Signal Site.
1226:Vanns, M.A., (1995),
1212:Solomon, B., (2010),
1188:, June and July 1957.
1123:A signal used in the
1122:
1054:advance clear to stop
980:
955:
919:
899:Staten Island Railway
885:
871:position light signal
864:
792:
757:
738:
727:
642:
562:
534:
491:On the approach to a
465:
331:
18:Position light signal
2658:Anti-trespass panels
1911:Automatic train stop
1474:Accessed 2011-09-11.
1441:. 5 September 2018.
720:Colour light signals
505:train order stations
390:Early signal systems
291:Colour-light signals
220:create a new article
212:improve this article
202:may not represent a
109:improve this article
2891:Rail infrastructure
2505:Classification yard
1435:"Signals explained"
1109:high speed railways
839:Regolamento Segnali
802:Searchlight signals
688:Hall Signal Company
2886:Railway signalling
2764:Motive power depot
2718:Signalling control
1751:Signalling control
1675:Railway signalling
1615:. 30 November 2015
1216:, Voyageur Press,
1214:Railroad Signaling
1158:Railway signalling
1129:
990:
958:
925:
888:
867:
799:
768:
758:Railway signal in
745:
733:
676:electric telegraph
672:optical telegraphs
652:
629:Mechanical signals
573:
537:
475:At the start of a
469:
334:
39:railway signalling
2873:
2872:
2591:Railway turntable
2412:
2363:
2362:
2173:Smith and Yardley
1589:. 6 November 2011
1222:978-0-7603-3881-0
682:by Major-General
655:three positions.
266:
265:
258:
248:
247:
240:
222:, as appropriate.
185:
184:
177:
159:
82:
16:(Redirected from
2898:
2768:Railway workshop
2484:Transition curve
2454:Fastening system
2408:
2390:
2383:
2376:
2367:
2239:Transport Canada
2123:General Electric
2060:Crossing signals
1941:Cityflo 650 CBTC
1863:Train protection
1668:
1661:
1654:
1645:
1625:
1624:
1622:
1620:
1613:Transport Canada
1605:
1599:
1598:
1596:
1594:
1584:
1576:
1570:
1569:
1567:
1565:
1559:
1548:
1539:
1533:
1532:
1530:
1529:
1510:
1504:
1503:
1501:
1500:
1485:"Railway Signal"
1481:
1475:
1468:
1462:
1452:
1446:
1445:
1431:
1425:
1422:
1416:
1413:
1407:
1404:
1398:
1388:
1382:
1379:
1373:
1372:
1369:www.railsigns.uk
1361:
1355:
1354:
1343:
1337:
1336:
1324:
1318:
1317:
1315:
1313:
1302:
1296:
1295:
1293:
1292:
1278:
1272:
1269:
1263:
1262:
1253:
1115:Signalling power
983:Utrecht Centraal
981:Dwarf signal at
830:Italian railways
612:
451:
439:
427:
415:
403:
288:
276:
261:
254:
243:
236:
232:
229:
223:
195:
194:
187:
180:
173:
169:
166:
160:
158:
124:"Railway signal"
117:
93:
85:
74:
52:
51:
44:
21:
2906:
2905:
2901:
2900:
2899:
2897:
2896:
2895:
2876:
2875:
2874:
2869:
2829:
2747:
2723:Structure gauge
2678:Defect detector
2650:
2642:
2488:
2444:Clip and scotch
2434:Breather switch
2400:
2394:
2364:
2359:
2248:
2197:
2091:
2055:
1857:
1831:Train detection
1826:
1793:
1745:
1677:
1672:
1634:
1629:
1628:
1618:
1616:
1607:
1606:
1602:
1592:
1590:
1582:
1578:
1577:
1573:
1563:
1561:
1557:
1546:
1541:
1540:
1536:
1527:
1525:
1512:
1511:
1507:
1498:
1496:
1483:
1482:
1478:
1469:
1465:
1453:
1449:
1433:
1432:
1428:
1423:
1419:
1414:
1410:
1405:
1401:
1389:
1385:
1380:
1376:
1363:
1362:
1358:
1345:
1344:
1340:
1326:
1325:
1321:
1311:
1309:
1304:
1303:
1299:
1290:
1288:
1280:
1279:
1275:
1271:Solomon, p. 156
1270:
1266:
1255:
1254:
1250:
1245:
1240:
1177:
1172:
1148:Highball Signal
1138:
1117:
1101:
1095:
1074:
1035:
1023:
1015:electrification
1007:
975:
973:Ground mounting
950:
948:Gantry mounting
930:
911:
909:Signal mounting
880:
859:
722:
637:
631:
623:
529:
523:or yard areas.
460:
459:
458:
455:
452:
443:
440:
431:
428:
419:
416:
407:
404:
392:
326:
320:
303:
302:
301:
300:
296:
295:
294:
293:(Great Britain)
292:
289:
281:
280:
277:
262:
251:
250:
249:
244:
233:
227:
224:
209:
196:
192:
181:
170:
164:
161:
118:
116:
106:
94:
53:
49:
42:
35:
32:level crossings
28:
23:
22:
15:
12:
11:
5:
2904:
2902:
2894:
2893:
2888:
2878:
2877:
2871:
2870:
2868:
2867:
2866:
2865:
2864:
2863:
2848:
2843:
2837:
2835:
2831:
2830:
2828:
2827:
2822:
2821:
2820:
2815:
2810:
2805:
2795:
2794:
2793:
2788:
2780:
2775:
2770:
2761:
2755:
2753:
2749:
2748:
2746:
2745:
2740:
2735:
2730:
2725:
2720:
2715:
2713:Railway signal
2710:
2705:
2700:
2698:Level crossing
2695:
2690:
2685:
2680:
2675:
2670:
2665:
2660:
2654:
2652:
2644:
2643:
2641:
2640:
2635:
2630:
2625:
2623:Track geometry
2620:
2615:
2614:
2613:
2603:
2598:
2593:
2588:
2587:
2586:
2581:
2576:
2574:overhead lines
2566:
2561:
2560:
2559:
2549:
2548:
2547:
2537:
2532:
2527:
2525:Gauntlet track
2522:
2517:
2512:
2507:
2502:
2496:
2494:
2490:
2489:
2487:
2486:
2481:
2476:
2471:
2469:Minimum radius
2466:
2461:
2456:
2451:
2446:
2441:
2436:
2431:
2426:
2421:
2415:
2413:
2402:
2401:
2398:infrastructure
2395:
2393:
2392:
2385:
2378:
2370:
2361:
2360:
2358:
2357:
2355:United Kingdom
2352:
2347:
2342:
2337:
2332:
2327:
2322:
2317:
2312:
2307:
2302:
2297:
2292:
2287:
2282:
2277:
2272:
2267:
2262:
2256:
2254:
2250:
2249:
2247:
2246:
2241:
2236:
2231:
2226:
2221:
2216:
2211:
2205:
2203:
2199:
2198:
2196:
2195:
2190:
2185:
2180:
2175:
2170:
2165:
2160:
2155:
2150:
2145:
2140:
2135:
2130:
2125:
2120:
2115:
2110:
2105:
2099:
2097:
2093:
2092:
2090:
2089:
2084:
2079:
2074:
2069:
2063:
2061:
2057:
2056:
2054:
2053:
2048:
2043:
2038:
2033:
2028:
2023:
2018:
2013:
2008:
2003:
1998:
1993:
1988:
1983:
1978:
1973:
1968:
1966:Integra-Signum
1963:
1958:
1953:
1948:
1943:
1938:
1933:
1928:
1923:
1918:
1913:
1908:
1903:
1898:
1893:
1888:
1883:
1878:
1873:
1867:
1865:
1859:
1858:
1856:
1855:
1850:
1845:
1840:
1834:
1832:
1828:
1827:
1825:
1824:
1819:
1814:
1812:Cab signalling
1809:
1803:
1801:
1795:
1794:
1792:
1791:
1786:
1781:
1776:
1771:
1766:
1761:
1755:
1753:
1747:
1746:
1744:
1743:
1738:
1733:
1728:
1723:
1718:
1713:
1708:
1703:
1698:
1693:
1687:
1685:
1679:
1678:
1673:
1671:
1670:
1663:
1656:
1648:
1642:
1641:
1633:
1632:External links
1630:
1627:
1626:
1600:
1571:
1534:
1505:
1476:
1463:
1454:Calvert, J.B.
1447:
1426:
1424:Solomon, p. 49
1417:
1415:Solomon, p. 50
1408:
1406:Solomon, p. 37
1399:
1390:Calvert, J.B.
1383:
1381:Solomon, p. 19
1374:
1365:"Main Signals"
1356:
1338:
1319:
1297:
1273:
1264:
1247:
1246:
1244:
1241:
1239:
1238:
1224:
1210:
1196:
1191:Calvert, J.B.
1189:
1178:
1176:
1173:
1171:
1170:
1165:
1160:
1155:
1150:
1145:
1139:
1137:
1134:
1116:
1113:
1099:Cab signalling
1097:Main article:
1094:
1093:Cab signalling
1091:
1087:track circuits
1073:
1070:
1034:
1031:
1022:
1019:
1011:retaining wall
1006:
1003:
974:
971:
949:
946:
929:
926:
910:
907:
879:
876:
858:
855:
836:) as from the
721:
718:
692:electric light
684:Charles Pasley
680:Board of Trade
668:New Cross Gate
633:Main article:
630:
627:
622:
619:
528:
525:
508:
507:
501:
498:
495:
493:level crossing
489:
486:
480:
457:
456:
453:
446:
444:
441:
434:
432:
429:
422:
420:
417:
410:
408:
405:
398:
395:
394:
393:
391:
388:
387:
386:
379:
376:
373:
370:
355:
352:
322:Main article:
319:
316:
307:railway signal
298:
297:
290:
283:
282:
278:
271:
270:
269:
268:
267:
264:
263:
246:
245:
206:of the subject
204:worldwide view
199:
197:
190:
183:
182:
97:
95:
88:
83:
57:
56:
54:
47:
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
2903:
2892:
2889:
2887:
2884:
2883:
2881:
2862:
2859:
2858:
2857:
2854:
2853:
2852:
2849:
2847:
2844:
2842:
2839:
2838:
2836:
2832:
2826:
2823:
2819:
2816:
2814:
2811:
2809:
2806:
2804:
2801:
2800:
2799:
2796:
2792:
2789:
2787:
2784:
2783:
2781:
2779:
2776:
2774:
2771:
2769:
2765:
2762:
2760:
2759:Coaling tower
2757:
2756:
2754:
2750:
2744:
2741:
2739:
2736:
2734:
2731:
2729:
2728:Signal bridge
2726:
2724:
2721:
2719:
2716:
2714:
2711:
2709:
2706:
2704:
2703:Loading gauge
2701:
2699:
2696:
2694:
2691:
2689:
2686:
2684:
2681:
2679:
2676:
2674:
2671:
2669:
2666:
2664:
2661:
2659:
2656:
2655:
2653:
2649:
2645:
2639:
2636:
2634:
2631:
2629:
2626:
2624:
2621:
2619:
2616:
2612:
2611:refuge siding
2609:
2608:
2607:
2604:
2602:
2599:
2597:
2594:
2592:
2589:
2585:
2582:
2580:
2577:
2575:
2572:
2571:
2570:
2567:
2565:
2562:
2558:
2557:tramway track
2555:
2554:
2553:
2550:
2546:
2543:
2542:
2541:
2538:
2536:
2533:
2531:
2528:
2526:
2523:
2521:
2518:
2516:
2513:
2511:
2508:
2506:
2503:
2501:
2498:
2497:
2495:
2491:
2485:
2482:
2480:
2477:
2475:
2472:
2470:
2467:
2465:
2462:
2460:
2457:
2455:
2452:
2450:
2447:
2445:
2442:
2440:
2437:
2435:
2432:
2430:
2427:
2425:
2422:
2420:
2417:
2416:
2414:
2411:
2407:
2403:
2399:
2391:
2386:
2384:
2379:
2377:
2372:
2371:
2368:
2356:
2353:
2351:
2348:
2346:
2343:
2341:
2338:
2336:
2333:
2331:
2328:
2326:
2325:North America
2323:
2321:
2318:
2316:
2313:
2311:
2308:
2306:
2303:
2301:
2298:
2296:
2293:
2291:
2288:
2286:
2283:
2281:
2278:
2276:
2273:
2271:
2268:
2266:
2263:
2261:
2258:
2257:
2255:
2251:
2245:
2242:
2240:
2237:
2235:
2232:
2230:
2227:
2225:
2222:
2220:
2217:
2215:
2212:
2210:
2207:
2206:
2204:
2202:Organisations
2200:
2194:
2191:
2189:
2186:
2184:
2181:
2179:
2176:
2174:
2171:
2169:
2166:
2164:
2161:
2159:
2156:
2154:
2153:Progress Rail
2151:
2149:
2146:
2144:
2141:
2139:
2136:
2134:
2131:
2129:
2126:
2124:
2121:
2119:
2116:
2114:
2111:
2109:
2106:
2104:
2101:
2100:
2098:
2096:Manufacturers
2094:
2088:
2085:
2083:
2080:
2078:
2075:
2073:
2070:
2068:
2065:
2064:
2062:
2058:
2052:
2049:
2047:
2044:
2042:
2041:Trainguard MT
2039:
2037:
2034:
2032:
2029:
2027:
2024:
2022:
2019:
2017:
2014:
2012:
2009:
2007:
2004:
2002:
1999:
1997:
1994:
1992:
1989:
1987:
1984:
1982:
1979:
1977:
1974:
1972:
1969:
1967:
1964:
1962:
1959:
1957:
1954:
1952:
1949:
1947:
1944:
1942:
1939:
1937:
1934:
1932:
1929:
1927:
1924:
1922:
1919:
1917:
1914:
1912:
1909:
1907:
1904:
1902:
1899:
1897:
1894:
1892:
1889:
1887:
1884:
1882:
1879:
1877:
1874:
1872:
1869:
1868:
1866:
1864:
1860:
1854:
1851:
1849:
1846:
1844:
1843:Track circuit
1841:
1839:
1836:
1835:
1833:
1829:
1823:
1820:
1818:
1815:
1813:
1810:
1808:
1805:
1804:
1802:
1800:
1796:
1790:
1787:
1785:
1782:
1780:
1777:
1775:
1772:
1770:
1767:
1765:
1762:
1760:
1757:
1756:
1754:
1752:
1748:
1742:
1739:
1737:
1734:
1732:
1729:
1727:
1724:
1722:
1719:
1717:
1714:
1712:
1709:
1707:
1704:
1702:
1699:
1697:
1694:
1692:
1689:
1688:
1686:
1684:
1683:Block systems
1680:
1676:
1669:
1664:
1662:
1657:
1655:
1650:
1649:
1646:
1639:
1636:
1635:
1631:
1614:
1610:
1604:
1601:
1588:
1581:
1575:
1572:
1556:
1552:
1545:
1538:
1535:
1524:on 2018-07-13
1523:
1519:
1515:
1509:
1506:
1495:on 2018-07-13
1494:
1490:
1486:
1480:
1477:
1473:
1467:
1464:
1460:
1457:
1451:
1448:
1444:
1440:
1436:
1430:
1427:
1421:
1418:
1412:
1409:
1403:
1400:
1396:
1393:
1387:
1384:
1378:
1375:
1370:
1366:
1360:
1357:
1352:
1348:
1342:
1339:
1334:
1330:
1329:"Post Plates"
1323:
1320:
1307:
1301:
1298:
1287:
1283:
1277:
1274:
1268:
1265:
1260:
1259:
1252:
1249:
1242:
1237:
1236:0-7110-2350-6
1233:
1230:, Ian Allan,
1229:
1225:
1223:
1219:
1215:
1211:
1209:
1208:0-86093-541-8
1205:
1201:
1197:
1194:
1190:
1187:
1185:
1180:
1179:
1174:
1169:
1166:
1164:
1161:
1159:
1156:
1154:
1151:
1149:
1146:
1144:
1141:
1140:
1135:
1133:
1126:
1121:
1114:
1112:
1110:
1106:
1100:
1092:
1090:
1088:
1084:
1080:
1071:
1069:
1067:
1063:
1062:clear to stop
1059:
1055:
1049:
1047:
1042:
1038:
1032:
1030:
1028:
1020:
1018:
1016:
1012:
1004:
1002:
999:
998:Rapid transit
995:
994:dwarf signals
988:
984:
979:
972:
970:
968:
967:signal bridge
964:
954:
947:
945:
943:
942:engine driver
939:
935:
928:Post mounting
927:
922:
918:
914:
908:
906:
904:
900:
895:
893:
884:
877:
875:
872:
863:
856:
854:
850:
848:
843:
841:
840:
835:
831:
826:
823:
818:
815:
811:
807:
803:
796:
791:
787:
785:
784:traffic light
781:
776:
773:
765:
761:
756:
752:
750:
742:
737:
730:
726:
719:
717:
715:
710:
708:
703:
701:
697:
693:
689:
685:
681:
677:
673:
669:
665:
661:
656:
650:
646:
641:
636:
628:
626:
620:
618:
614:
611:
604:
602:
598:
594:
590:
585:
583:
582:in advance of
579:
570:
566:
561:
557:
554:
550:
546:
542:
539:Signals have
533:
526:
524:
522:
517:
513:
506:
502:
499:
496:
494:
490:
487:
485:
481:
478:
474:
473:
472:
464:
450:
445:
438:
433:
426:
421:
414:
409:
402:
397:
389:
384:
380:
377:
374:
371:
368:
364:
361:(also called
360:
356:
353:
350:
349:
348:
345:
343:
338:
330:
325:
317:
315:
313:
308:
287:
275:
260:
257:
242:
239:
231:
228:November 2023
221:
217:
213:
207:
205:
198:
189:
188:
179:
176:
168:
157:
154:
150:
147:
143:
140:
136:
133:
129:
126: –
125:
121:
120:Find sources:
114:
110:
104:
103:
98:This article
96:
92:
87:
86:
81:
79:
72:
71:
66:
65:
60:
55:
46:
45:
40:
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2743:Wayside horn
2712:
2693:Interlocking
2673:Catch points
2633:Water trough
2535:Passing loop
2515:Pocket track
2500:Balloon loop
2464:Ladder track
2183:Union Switch
2087:Wayside horn
1931:Catch points
1838:Axle counter
1798:
1769:Interlocking
1721:Moving block
1617:. Retrieved
1603:
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1574:
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1522:the original
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1493:the original
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1439:Network Rail
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729:Network Rail
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621:Signal forms
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601:Interlocking
597:Grade Signal
596:
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512:double track
509:
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383:train orders
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165:January 2021
162:
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138:
131:
119:
107:Please help
102:verification
99:
75:
68:
62:
61:Please help
58:
2668:Buffer stop
2628:Water crane
2540:Track gauge
2479:Tie/Sleeper
2345:Switzerland
2320:New Zealand
2315:Netherlands
2021:Slide fence
1774:Lever frame
1638:Signal Page
1461:2004-08-10.
1397:2007-05-04.
1195:2007-05-04.
1125:Delhi metro
1105:cab signals
1083:interlocked
987:Netherlands
772:signal head
749:light bulbs
714:telegraphed
645:Kościerzyna
569:Expect Stop
545:indications
484:swingbridge
2880:Categories
2841:Industrial
2825:Water stop
2786:for trains
2778:Roundhouse
2752:Structures
2738:Train stop
2688:Guard rail
2663:Block post
2651:and safety
2648:Signalling
2579:third rail
2552:Rail track
2545:dual gauge
2429:Baulk road
2253:By country
2036:Train stop
2001:RS4 Codici
1759:Block post
1564:30 October
1528:2022-02-20
1499:2022-02-20
1291:2021-04-19
1175:References
1079:signal box
780:multi-unit
764:Ks signals
610:Mastschild
593:permissive
578:in rear of
553:indication
135:newspapers
64:improve it
2791:for goods
2733:Tell-tale
2564:Rail yard
2530:Guide bar
2510:Headshunt
2493:Trackwork
2459:Fishplate
2449:Date nail
2410:(history)
2260:Australia
2113:AŽD Praha
2072:Crossbuck
1976:Crocodile
1619:25 August
1593:25 August
1027:filaments
1021:Filaments
1017:support.
707:fail-safe
696:oil lamps
381:That the
216:talk page
70:talk page
2846:Military
2803:building
2773:Platform
2683:Derailer
2601:Roll way
2520:Junction
2419:Axe ties
2350:Thailand
2158:Safetran
2148:Magnetic
2133:Griswold
2082:E-signal
1555:Archived
1186:Magazine
1136:See also
1046:failsafe
760:Ploiești
589:absolute
479:of track
210:You may
2856:station
2851:Private
2798:Station
2474:Profile
2424:Ballast
2295:Germany
2285:Finland
2270:Belgium
2265:Bavaria
2168:Siemens
2143:Hitachi
2118:Federal
2103:Adtranz
2006:SelTrac
1853:Treadle
1799:Signals
1333:sh1.org
1312:7 March
921:Swedish
662:on the
541:aspects
521:sidings
477:section
367:turnout
149:scholar
2618:Switch
2606:Siding
2406:Tracks
2340:Sweden
2335:Poland
2330:Norway
2300:Greece
2290:France
2275:Canada
2178:Thales
2108:Alstom
2077:Wigwag
1956:EBICAB
1926:Balise
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1220:
1206:
1184:Trains
1143:Gantry
963:gantry
743:(Stop)
649:Poland
549:aspect
547:. The
363:switch
359:points
340:Under
312:driver
151:
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130:
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2834:Types
2813:ghost
2808:clock
2782:Shed
2396:Rail
2310:Japan
2305:Italy
2280:China
2214:AREMA
2163:Saxby
2016:SACEM
1961:IIATS
1886:ATACS
1731:Token
1587:NORAC
1583:(PDF)
1558:(PDF)
1547:(PDF)
1243:Notes
1005:Other
817:relay
565:Muhos
357:That
218:, or
156:JSTOR
142:books
2861:list
2818:list
2439:Cant
2234:IRSE
2229:HMRI
2138:Hall
1881:ASFA
1876:ALSN
1621:2020
1595:2020
1566:2022
1314:2013
1232:ISBN
1218:ISBN
1204:ISBN
1066:stop
1058:stop
938:mast
934:post
847:LEDs
814:D.C.
810:A.C.
770:The
580:and
543:and
128:news
2638:Wye
2244:UIC
2224:FRA
2219:ERA
2209:AAR
2128:GRS
996:).
965:or
936:or
812:or
741:Hp0
647:in
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