Railway signalling (BE), also called railroad signaling (AE), is a system used to control the movement of railway traffic. Trains move on fixed rails, making them uniquely susceptible to collision. This susceptibility is exacerbated by the enormous weight and inertia of a train, which makes it difficult to quickly stop when encountering an obstacle. In the UK, the Regulation of Railways Act 1889 introduced a series of requirements on matters such as the implementation of interlocked block signalling and other safety measures as a direct result of the Armagh rail disaster in that year.
A third rail, also known as a live rail, electric rail or conductor rail, is a method of providing electric power to a railway locomotive or train, through a semi-continuous rigid conductor placed alongside or between the rails of a railway track. It is used typically in a mass transit or rapid transit system, which has alignments in its own corridors, fully or almost fully segregated from the outside environment. Third-rail systems are usually supplied from direct current electricity.
Rail transport terms are a form of technical terminology applied to railways. Although many terms are uniform across different nations and companies, they are by no means universal, with differences often originating from parallel development of rail transport systems in different parts of the world, and in the national origins of the engineers and managers who built the inaugural rail infrastructure. An example is the term railroad, used in North America, and railway, generally used in English-speaking countries outside North America and by the International Union of Railways. In English-speaking countries outside the United Kingdom, a mixture of US and UK terms may exist.
The Train Protection & Warning System (TPWS) is a train protection system used throughout the British passenger main-line railway network, and in Victoria, Australia.
The Automatic Warning System (AWS) provides a train driver with an audible indication of whether the next signal they are approaching is clear or at caution. Depending on the upcoming signal state, the AWS will either produce a 'horn' sound, or a 'bell' sound. If the train driver fails to acknowledge a warning indication, an emergency brake application is initiated by the AWS. However if the driver correctly acknowledges the warning indication by pressing an acknowledgement button, then a visual 'sunflower' is displayed to the driver, as a reminder of the warning.
Part of a railway signalling system, a train stop, trip stop or tripcock is a train protection device that automatically stops a train if it attempts to pass a signal when the signal aspect and operating rules prohibit such movement, or if it attempts to pass at an excessive speed.
Cab signaling is a railway safety system that communicates track status and condition information to the cab, crew compartment or driver's compartment of a locomotive, railcar or multiple unit. The information is continually updated giving an easy to read display to the train driver or engine driver.
Automatic train control (ATC) is a general class of train protection systems for railways that involves a speed control mechanism in response to external inputs. For example, a system could effect an emergency brake application if the driver does not react to a signal at danger. ATC systems tend to integrate various cab signalling technologies and they use more granular deceleration patterns in lieu of the rigid stops encountered with the older automatic train stop (ATS) technology. ATC can also be used with automatic train operation (ATO) and is usually considered to be the safety-critical part of a railway system.
A track circuit is an electrical device used to prove the absence of a train on rail tracks to signallers and control relevant signals. An alternative to track circuits are axle counters.
Automatic train stop or ATS is a system on a train that automatically stops a train if certain situations occur to prevent accidents. In some scenarios it functions as a type of dead man's switch. Automatic train stop differs from the concept of Automatic Train Control in that ATS usually does not feature an onboard speed control mechanism.
Linienzugbeeinflussung is a cab signalling and train protection system used on selected German and Austrian railway lines as well as on the AVE and some commuter rail lines in Spain. The system was mandatory where trains were allowed to exceed speeds of 160 km/h (99 mph) in Germany and 220 km/h (140 mph) in Spain. It is also used on some slower railway and urban rapid transit lines to increase capacity. The German Linienzugbeeinflussung translates to continuous train control, literally: linear train influencing. It is also called linienförmige Zugbeeinflussung.
PZB or Indusi is an intermittent cab signalling system and train protection system used in Germany, Austria, Slovenia, Croatia, Romania, Israel, Serbia, on two lines in Hungary, on the Tyne and Wear Metro in the United Kingdom, and formerly on the Trillium Line in Canada.
Standards for North American railroad signaling in the United States are issued by the Association of American Railroads (AAR), which is a trade association of the railroads of Canada, the US, and Mexico. Their system is loosely based on practices developed in the United Kingdom during the early years of railway development. However, North American practice diverged from that of the United Kingdom due to different operating conditions and economic factors between the two regions. In Canada, the Canadian Rail Operating Rules (CROR) are approved by the Minister of Transport under the authority of the Railway Safety Act. Each railway company or transit authority in Canada issues its own CROR rulebook with special instructions peculiar to each individual property. Among the distinctions are:
A train protection system is a railway technical installation to ensure safe operation in the event of human error.
North American railroad signals generally fall into the category of multi-headed electrically lit units displaying speed-based or weak route signaling. Signals may be of the searchlight, color light, position light, or color position light types, each displaying a variety of aspects which inform the locomotive operator of track conditions so that they may keep their train under control and able to stop short of any obstruction or dangerous condition.
Rail speed limits in the United States are regulated by the Federal Railroad Administration. Railroads also implement their own limits and enforce speed limits. Speed restrictions are based on a number of factors including curvature, signaling, track condition, and the presence of grade crossings. Like road speed limits in the United States, speed limits for tracks and trains are measured in miles per hour (mph).
Pulse code cab signaling is a form of cab signaling technology developed in the United States by the Union Switch and Signal corporation for the Pennsylvania Railroad in the 1920s. The 4-aspect system widely adopted by the PRR and its successor railroads has become the dominant railroad cab signaling system in North America with versions of the technology also being adopted in Europe and rapid transit systems. In its home territory on former PRR successor Conrail owned lines and on railroads operating under the NORAC Rulebook it is known simply as Cab Signaling System or CSS.
Belgian railway signalling is the signalling in effect on the Belgian rail network currently operated by Infrabel.
ALSN is a train control system used widely on the main lines of the ex-Soviet states. It uses modulated pulses inducted into rails similar to the Italian RS4 Codici and American Pulse Code Cab Signaling. On high-speed lines the variant ALS-EN (АЛС-ЕН) is used which takes advantage of a double phase difference modulation of the carrier wave.
The Southern California Railway Museum, formerly known as the Orange Empire Railway Museum, is a railroad museum in Perris, California, United States. It was founded in 1956 at Griffith Park in Los Angeles before moving to the former Pinacate Station as the "Orange Empire Trolley Museum" in 1958. It was renamed "Orange Empire Railway Museum" in 1975 after merging with a museum then known as the California Southern Railroad Museum, and adopted its current name in 2019. The museum also operates a heritage railroad on the museum grounds.
