321:. Although loops are standard, buffer stops may be fitted with 'mini loops', due to the very low approach speed, usually 10 mph. When buffer stops were originally fitted with TPWS using standard loops there were many instances of false applications, causing delays whilst it reset, with trains potentially blocking the station throat, plus the risk of passengers standing to alight being thrown over by the sudden braking. This problem arose when a train passed over the arming loop so slowly that it was still detected by the train's receiver after the on-board timer had completed its cycle. The timer would reset and begin timing again, and the trigger loop then being detected within this second timing cycle would lead to a false intervention. As a temporary solution, drivers were instructed to pass the buffer stop OSSs at 5 mph, eliminating the problem, but meaning that trains no longer had the momentum to roll to the normal stopping point and requiring drivers to apply power beyond the OSS, just a short distance from the buffers, arguably making a buffer stop collision more likely than before TPWS was fitted. The redesigned 'mini loops', roughly a third the length of the standard ones, eliminate this problem, although due to the low speed and low margin, buffer stop OSSs are still a major cause of TPWS trips.
255:
155:
414:, where a driver repeatedly cancelled the AWS warning without applying the brakes, passing the danger signal at high speed. Purley was one of several high profile SPAD crashes in the late 1980s, that led to the initial plan in the 1990s for the mass rollout of ATP, that was subsequently canceled in 1994 to be replaced by TPWS.
189:
would be nominated the ânormal directionâ and fitted with âNDâ equipment. The other signal would be nominated the âopposite directionâ and fitted with âODâ equipment. Opposite direction TPWS transmission frequencies are slightly different, working at 64.75 (OSS arming), 66.75 (TSS arming), and 65.75 kHz (common trigger).
287:
Temporarily isolating the TPWS does not affect the AWS. The driver must reinstate the TPWS immediately at the point where normal working is resumed. As a safety feature, if they forget to do this, the TPWS will be reinstated on the next occasion that the driver's desk is shut down and then opened up again.
417:
Supporters of TPWS claim that even where it could not prevent accidents due to SPADs, it would likely reduce the impact, and reduce or eliminate fatalities, by at least slowing the train down. However, it is likely that in those cases the driver would have applied the emergency brakes well before the
304:
system causes. The first known installation of such a system is at Ilford Depot. TPWS equipped depot protection systems are suitable only for locations where vehicles are driven in and out of the maintenance building from a leading driving cab - they are not suitable for use with loose coaching stock
299:
is to equip the system with TPWS. This equipment safeguards staff from unauthorised movements by using the TPWS equipment. Any unplanned movement will cause the train to automatically come to a stand when it has passed the relevant signal set at danger. This has the added benefit of preventing damage
406:
remarked that TPWS was "in terms of avoiding âATP preventable accidentsâ it is about 70% effective.", highlighting the speed limitation. That 2000 study did still conclude that TPWS was good solution for the short term of 10â15 years, but stressed that
European Train Control system was the long term
241:
If the loops are energised, an aerial on the underside of the train picks up the radio frequency signal and passes it to the receiver. A timer measures how long it takes to pass between the arming and trigger loops. This time is used to check the speed, and if it is higher than the TPWS 'set speed',
166:
The first pair, the
Overspeed Sensor System (OSS), is sited at a position determined by line speed and gradient. The loops are separated by a distance that should not be traversed within less than a pre-determined period of time of about one second if the train is running at a safe speed approaching
286:
There is also a separate TPWS Temporary
Isolation Switch located out of reach of the driver's desk. This is operated by the driver when the train is being worked in degraded conditions such as Temporary Block Working where multiple signals need to be passed at danger with the signalman's authority.
342:
Standard TPWS installations can only bring a train to a stop prior to passing a red signal, at 74 miles per hour (119 km/h). In 2001, it was observed that roughly one-third of the UK railway allows for a speed above 75 miles per hour (121 km/h). Further this assumes the train's brakes is
188:
Where trains are signalled in opposite directions on an individual line it could be possible for an unwarranted TPWS intervention to occur as a train travelled between an OSS arming and either trigger loops that were in fact associated with different signals. To cater for this situation one signal
177:
The other pair of loops is back to back at the signal, and is called a Train Stop System (TSS). The 'arming' and 'trigger' loops work at 66.25 kHz and 65.25 kHz respectively. The brakes will be applied if the on-train equipment detects both frequencies together after having detected the
76:
is installed with a third transmitter further in rear of the signal increasing the effectiveness to 100 mph (160 km/h). When installed in conjunction with signal controls such as 'double blocking' (i.e. two red signal aspects in succession), TPWS can be fully effective at any realistic
328:
protection techniques, used TPWS with outer home signals that protect converging junctions with a higher than average risk by controlling the speed of an approaching train an extra signal section in rear of the junction. If this fails the resultant TPWS application of brakes will stop the train
369:
why a driver might be required to pass a signal at danger with authority. The signaller will advise the driver to pass the signal at danger, proceed with caution, be prepared to stop short of any obstruction, and then obey all other signals. Immediately before moving, the driver will press the
68:
A standard installation consists of an on-track transmitter adjacent to a signal, activated when the signal is at danger. A train that passes the signal will have its emergency brake activated. If the train is travelling at speed, this may be too late to stop it before the point of collision,
421:
While it has been noted that there have been very few fatalities since the fitting of TPWS that would have been prevented had ATP been fitted instead. This overlooks that during the delay between the decision to cancel ATP and replace it with TPWS and the actual roll out of TPWS that
262:
Every driving cab has a TPWS control panel, located where the driver can see it from their desk. There are two types of panel; the original 'standard' type, and a more recent 'enhanced' version, which gives separate indications for a brake demand caused by a SPAD, Overspeed or AWS.
242:
an emergency brake application is initiated. If the train is travelling slower than the TPWS set speed, but then passes the signal at danger, the aerial will receive the signal from the energised Train Stop System loops, and the brake will be applied to stop the train within the
162:
In a standard installation there are two pairs of loops, colloquially referred to as "grids" or "toast racks". Both pairs consist of an 'arming' and a 'trigger' loop. If the signal is at danger the loops will be energised. If the signal is clear, the loops will de-energise.
178:
arming frequency alone. Thus, an energised TSS is effective at any speed, but only if a train passes it in the right direction. Since a train may be required to pass a signal at danger during failure etc., the driver has the option to override a TSS, but not an OSS.
305:
or wagon maintenance, where vehicle movements are undertaken by a propelling shunting loco (in this case the lead vehicles would not be equipped with the relevant TPWS safety equipment), nor will it prevent a run-away vehicle from entering a protected work area.
167:
the signal at danger. The exact timings are 974 milliseconds for passenger trains and 1218 milliseconds for freight trains, determined by equipment on the train. Freight trains use the 1.25 times longer timing because of their different braking characteristics.
197:
At the lineside there are two modules associated with each set of loops: a Signal
Interface Module (SIM) and an OSS or TSS module. These generate the frequencies for the loops, and prove the loops are intact. They interface with the signalling system.
142:. When the train's TPWS receiver passes over the first loop a timer begins to count down. If the second loop is passed before the timer has reached zero, the TPWS will activate. The greater the line speed, the more widely spaced the two loops will be.
246:. Multiple unit trains have an aerial at each end. Vehicles that can operate singly (single car DMUs and locomotives) only have one aerial. This would be either at the front or rear of it depending on the direction the vehicle was moving in.
57:, the purpose of TPWS is to stop a train by automatically initiating a brake demand, where TPWS track equipment is fitted, if the train has: passed a signal at danger without authority; approached a signal at danger too fast; approached a
108:
system was not economical, costing ÂŁ600,000,000 equivalent to ÂŁ979,431,929 in 2019 to implement, compared to value in lives saved: ÂŁ3-ÂŁ4 million (4,897,160 - 6,529,546 in 2019), per life saved, which was estimated to be 2.9 per year.
137:
A pair of electronic loops are placed 50â450 metres on the approach side of the signal, energized when it is at danger. The distance between the loops determines the minimum speed at which the on board equipment will apply the train's
398:
Critics, such as those representing victims of the
Ladbroke Grove and Southhall rail crashes, and ASLEF and RMT rail unions pushed for the abandonment of TPWS in the late 1990s in favor of continuing with British Rail's ATP project.
515:
Braking capability is "conventionally measured as a percentage of âreverse accelerationâ represented by gravity (g)." In 2001, the best braking available was "enhanced emergency" braking" producing a braking force equivalent to
69:
therefore a second transmitter may be placed on the approach to the signal that applies the brakes on trains going too quickly to stop at the signal, positioned to stop trains approaching at up to 75 mph (120 km/h).
119:
report found that TPWS had a number of limitations, and that while it provided a relatively cheap stop-gap prior to the widescale introduction of ATP and ERTMS, nothing should impede the installation of the much more capable
145:
There is another pair of loops at the signal, also energised when the signal is at danger. These are end to end, and thus will initiate a brake application on a train about to pass a signal at danger regardless of speed.
373:
The driver must then proceed at a speed which enables them to stop within the distance that they can see to be clear. Even if it appears that the section is clear to the next signal, they must still exercise caution.
273:. It ignores the TPWS TSS loops for approximately 20 seconds (generally for passenger trains) or 60 seconds (generally for slower accelerating freight trains) or until the loops have been passed, whichever is sooner.
1454:
115:
The rollout of TPWS accelerated when the
Railway Safety Regulations 1999 came into force in 2003, requiring the installation of train stops at a number of types of location. However, in March 2001 the
536:
283:
The "Temporary
Isolation/Fault" indicator lamp will flash if there is a TPWS system fault, or will show a steady illumination if the "Temporary Isolation Switch" has been activated.
1652:
347:
were not capable of doing, despite having a top speed of 125 miles per hour (201 km/h). TPWS-A was capable of stopping a train up to 100 miles per hour (160 km/h).
430:
both occurred, accidents that were ATP preventable, and occurred on the Great
Western line, which had been outfitted with ATP as part of the pilot studies in the early-90s.
270:
390:
produced wheel slide and the train therefore was not brought to a stop prior to the collision point. (ATP would not have prevented this circumstance either).
313:
Certain signals may have multiple OSSes fitted. Alternatively, usually due to low line speeds, an OSS may not be fitted. An example of this is a terminal
594:
861:
280:
system and the TPWS system are inter-linked and if either of these has initiated a brake application, the "Brake Demand" indicator lamp will flash.
544:
112:
Trial installations of track side and train mounted equipment were made in 1997, with trials and development continuing over the next two years.
65:(SPADs) but to mitigate the consequences of a SPAD, by preventing a train that has had a SPAD from reaching a conflict point after the signal.
366:
356:
1409:
1319:
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185:
associated with a main aspect signal is cleared for a shunting movement, the TSS loops are de-energised, but the OSS loops remain active.
1399:
1344:
495:
105:
892:
370:"Trainstop Override" button on the TPWS panel, so that the train can pass the signal without triggering the TPWS to apply the brakes.
1026:
921:
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1309:
17:
477:
473:
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which accomplish a similar task using electro-mechanical technology. Buffer stop protection using train stops is known as â
1464:
1414:
1384:
362:. However, on those occasions there are strict rules governing the actions of drivers, train speed, and the use of TPWS.
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1339:
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935:. Health & Safety Commission. pp. 10, 54â55, 70, 86, 1 05 (PDF Page 25, 69â70, 85, 101, 120).
1773:
1728:
1631:
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1334:
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383:
43:
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1329:
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139:
62:
39:
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Since 1996, an older variant of TPWS, called the
Auxiliary Warning System, has been used by the
1566:
1556:
1505:
1424:
1419:
1149:
329:
before the point of conflict is reached. This system is referred to as TPWS OS (Outer Signal).
950:
1793:
1227:
1217:
1179:
1174:
387:
893:"Collision between passenger trains at Salisbury Tunnel Junction. Wiltshire 31 October 2021"
317:
starting signal. An OSS on its own may be used to protect a permanent speed restriction, or
1349:
789:
761:
570:
453:
47:
687:
Signal passed at danger and subsequent near miss at Didcot North junction (22 August 2007)
8:
1576:
1459:
427:
410:
Notably, the combination of TPWS and AWS is least effective in accidents like the one at
1189:
1113:
343:
capable of providing a brake force of 12%g. A number of train types, most notably, the
1611:
1515:
1291:
1039:
999:
959:
834:
727:
654:
629:
266:
The standard type consists of two circular indicator lamps and a square push button.
1677:
1606:
1581:
1561:
1379:
344:
314:
498:- A cab signaling and train control system that was not adopted for widespread use
158:
A TPWS transmitter loop, one of a pair that form an
Overspeed Sensor System (OSS)
1404:
1250:
1237:
443:
1808:
1591:
1479:
1281:
61:
too fast; approached buffer stops too fast. TPWS is not designed to prevent
1525:
1369:
1276:
1207:
1159:
1068:
827:
The Southall and Ladbroke Grove Joint Inquiry into Train Protection Systems
720:
The Southall and Ladbroke Grove Joint Inquiry into Train Protection Systems
97:
1551:
1212:
318:
1601:
1474:
1439:
1197:
833:. Her Majestyâs Stationery Office. pp. 99â100 (PDF Page 114â115).
81:
952:
Automatic Train Protection for the Railway Network in Britain: A study
862:"Rulebook Master: Module S5. Section 4.2 "Passing a signal at danger""
1510:
1082:
457:
101:
680:"Appendix E - History of the Train Protection Warning System (TPWS)"
1596:
1520:
986:
917:
817:
710:
1541:
1444:
386:, because although the train went to full emergency braking, the
324:
Recent applications in the UK have, in conjunction with advanced
174:. The second, 'trigger', loop has a frequency of 65.25 kHz.
1546:
1394:
1364:
649:
Vaughan, Adrian (2009). "9 - 'Safety is justified as safety'".
301:
567:"AWS & TPWS Handbook: Section 2.1.2 "The purpose of TPWS""
1324:
492:- A British Rail developed warning system used alongside TPWS
254:
171:
300:
to the infrastructure and traction and rolling stock that a
154:
1314:
350:
537:"Step Change in Safety Delivered On Time and Under Budget"
404:
Automatic Train Protection for the rail network in Britain
170:
The first, 'arming', loop emits a frequency of 64.25
27:
Train protection system in the UK and Victoria, Australia
653:(1st ed.). Ian Allan Publishing. pp. 102â107.
269:
The push switch marked "Train Stop Override" is used to
104:, following a determination in 1994 that British Rail's
626:
British Rail 1974â97: From Integration to Privatisation
628:. Oxford: Oxford University Press. pp. 355â360.
393:
290:
949:
Davies, David (February 2000). "Executive Summary".
355:
TPWS has no ability to regulate speed after a train
867:. Rail Safety & Standards Board. Archived from
786:"AWS & TPWS Handbook, 2.3.3 TPWS Control Panel"
705:
703:
228:TPWS control panel (standard or enhanced version).
926:"The Joint Inquiry into Train Protection Systems"
898:. Rail Accidents Investigation Branch. p. 90
1806:
700:
543:. Network Rail. 29 December 2003. Archived from
1032:The Ladbroke Grove Rail Inquiry - Part 1 Report
812:
810:
1098:
944:
942:
674:
672:
670:
1410:Interoperable Communications Based Signaling
1069:Train Protection & Warning System (TPWS)
807:
1345:Automatic Train Protection (United Kingdom)
958:. Royal Academy of Engineering. p. 5.
910:
854:
117:Joint Inquiry Into Train Protection Systems
1105:
1091:
939:
752:
750:
667:
992:The Southall Rail Accident Inquiry Report
816:
709:
623:
351:Signals passed at danger with permission
253:
153:
1310:Advanced Civil Speed Enforcement System
747:
648:
617:
559:
210:ND OSS Modules are colour coded yellow
14:
1807:
1112:
1025:
948:
271:pass a signal at danger with authority
221:Every traction unit is fitted with a:
207:OD TSS Modules are colour coded brown
204:ND TSS Modules are colour coded green
42:used throughout the British passenger
1470:Train Protection & Warning System
1086:
916:
885:
464:magnets and with full-length overlaps
295:An alternative to using derailers in
216:
213:OD OSS Modules are colour coded blue
192:
149:
32:Train Protection & Warning System
1203:Integrated Electronic Control Centre
642:
258:'Standard' TPWS panel in driving cab
1465:Train automatic stopping controller
1385:Continuous Automatic Warning System
1038:. Her Majestyâs Stationery Office.
998:. Her Majesty's Stationery Office.
985:
726:. Her Majestyâs Stationery Office.
433:
377:
249:
72:At around 400 high-risk locations,
24:
1145:Communications-based train control
394:Compared with other safety systems
297:Depot Personnel Protection Systems
291:TPWS use in depot personnel safety
25:
1831:
1062:
201:SIM Modules are colour coded red
758:"AWS & TPWS Handbook, 2.2.3"
601:. 6 October 2004. Archived from
234:TPWS temporary isolation switch.
231:AWS/TPWS acknowledgement button.
1627:Westinghouse Brake & Signal
1390:ContrĂ´le de vitesse par balises
1256:North American railroad signals
1019:
979:
595:"TPWS PLUS GETS OFF THE GROUND"
509:
450:magnets and with short overlaps
237:AWS/TPWS full isolation switch.
127:
55:Rail Safety and Standards Board
1485:Transmission balise-locomotive
1450:Sistema Controllo Marcia Treno
1360:Automatische treinbeĂŻnvloeding
1246:Application of railway signals
778:
587:
529:
332:
59:reduction in permissible speed
13:
1:
1435:PunktfĂśrmige Zugbeeinflussung
1155:European Train Control System
523:
308:
122:European Train Control System
1375:Chinese Train Control System
1165:Radio Electronic Token Block
651:The Greatest Railway Blunder
541:networkrailmediacentre.co.uk
438:The TPWS system is used in:
7:
1140:Centralized traffic control
689:. November 2008. p. 62
483:
382:TPWS failed to prevent the
132:
10:
1836:
1340:Automatic train protection
496:Automatic Train Protection
357:passes a signal at danger
106:Automatic Train Protection
91:
1691:
1640:
1632:Westinghouse Rail Systems
1534:
1498:
1490:Transmission Voie-Machine
1335:Automatic train operation
1300:
1287:Track circuit interrupter
1269:
1236:
1188:
1135:Automatic block signaling
1130:Absolute block signalling
1120:
599:Network Rail Media Centre
384:2021 Salisbury rail crash
88:' or 'Moorgate controlâ.
44:main-line railway network
1815:Train protection systems
1430:Pulse code cab signaling
1355:Automatic Warning System
1261:Railway semaphore signal
1223:Solid State Interlocking
624:Gourvish, Terry (2002).
502:
490:Automatic Warning System
337:
80:TPWS is not the same as
63:signals passed at danger
1330:Automatic train control
470:Mumbai Suburban Railway
40:train protection system
18:Overspeed Sensor System
1506:Level crossing signals
1425:Positive Train Control
1420:Linienzugbeeinflussung
1150:Direct traffic control
1078:Slideshow on TPWS v1.3
569:. RSSB. Archived from
259:
159:
96:TPWS was developed by
1228:Westlock Interlocking
1218:Rail operating centre
1180:Train order operation
1175:Track Warrant Control
257:
157:
1350:Automatic train stop
989:(24 February 2000).
547:on 28 September 2007
53:According to the UK
428:Southall rail crash
86:Moorgate protection
1190:Signalling control
1114:Railway signalling
795:on 5 December 2016
418:overspeed sensor.
260:
217:On-train equipment
193:Location equipment
160:
150:On-track equipment
100:and its successor
1802:
1801:
1612:Smith and Yardley
824:(29 March 2001).
717:(29 March 2001).
472:in India, on the
183:subsidiary signal
16:(Redirected from
1827:
1678:Transport Canada
1562:General Electric
1499:Crossing signals
1380:Cityflo 650 CBTC
1302:Train protection
1107:
1100:
1093:
1084:
1083:
1057:
1056:
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1052:
1037:
1029:(19 June 2001).
1023:
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933:Railways Archive
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788:. Archived from
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766:
760:. Archived from
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707:
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660:978 07110 3274 3
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434:Locations in use
388:slick conditions
378:Track conditions
315:station platform
250:In-cab equipment
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1270:Train detection
1265:
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1027:Cullen, William
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922:Cullen, William
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822:Cullen, William
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715:Cullen, William
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140:emergency brake
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5:
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1496:
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1487:
1482:
1477:
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1432:
1427:
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1412:
1407:
1405:Integra-Signum
1402:
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1387:
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1377:
1372:
1367:
1362:
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1289:
1284:
1279:
1273:
1271:
1267:
1266:
1264:
1263:
1258:
1253:
1251:Cab signalling
1248:
1242:
1240:
1234:
1233:
1231:
1230:
1225:
1220:
1215:
1210:
1205:
1200:
1194:
1192:
1186:
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1183:
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1177:
1172:
1167:
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1157:
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1142:
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1132:
1126:
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1109:
1102:
1095:
1087:
1081:
1080:
1075:
1064:
1063:External links
1061:
1059:
1058:
1044:
1018:
1004:
978:
964:
938:
909:
884:
853:
839:
806:
777:
746:
732:
699:
666:
659:
641:
634:
616:
605:on 5 June 2016
586:
558:
527:
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519:
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501:
500:
499:
493:
485:
482:
466:
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451:
444:United Kingdom
435:
432:
424:Ladbroke Grove
402:A 2000 study,
395:
392:
379:
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359:with authority
352:
349:
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336:
334:
331:
310:
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292:
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251:
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225:TPWS receiver.
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93:
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26:
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6:
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1764:North America
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1643:
1641:Organisations
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1592:Progress Rail
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1535:Manufacturers
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1514:
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1509:
1507:
1504:
1503:
1501:
1497:
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1483:
1481:
1480:Trainguard MT
1478:
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1311:
1308:
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1283:
1282:Track circuit
1280:
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1199:
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1146:
1143:
1141:
1138:
1136:
1133:
1131:
1128:
1127:
1125:
1123:
1122:Block systems
1119:
1115:
1108:
1103:
1101:
1096:
1094:
1089:
1088:
1085:
1079:
1076:
1074:
1070:
1067:
1066:
1047:
1045:0 7176 2056 5
1041:
1034:
1033:
1028:
1022:
1007:
1005:0 7176 1757 2
1001:
994:
993:
988:
982:
967:
965:1 871634 88 1
961:
954:
953:
945:
943:
934:
927:
923:
919:
913:
894:
888:
874:on 2018-08-10
870:
863:
857:
842:
840:0 7176 1998 2
836:
829:
828:
823:
819:
813:
811:
791:
787:
781:
767:on 2016-12-05
763:
759:
753:
751:
735:
733:0 7176 1998 2
729:
722:
721:
716:
712:
706:
704:
688:
681:
675:
673:
671:
662:
656:
652:
645:
637:
635:0-19-925005-7
631:
627:
620:
604:
600:
596:
590:
576:on 2016-12-05
572:
568:
562:
546:
542:
538:
532:
528:
512:
508:
497:
494:
491:
488:
487:
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479:
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439:
431:
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413:
408:
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371:
368:
363:
361:
360:
348:
346:
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327:
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298:
288:
284:
281:
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256:
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208:
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156:
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143:
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125:
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110:
107:
103:
99:
89:
87:
83:
78:
75:
70:
66:
64:
60:
56:
51:
50:, Australia.
49:
45:
41:
37:
33:
19:
1622:Union Switch
1526:Wayside horn
1469:
1370:Catch points
1277:Axle counter
1208:Interlocking
1160:Moving block
1073:Railsigns.uk
1072:
1049:. Retrieved
1031:
1021:
1009:. Retrieved
991:
981:
969:. Retrieved
951:
932:
912:
900:. Retrieved
887:
876:. Retrieved
869:the original
856:
844:. Retrieved
826:
797:. Retrieved
790:the original
780:
769:. Retrieved
762:the original
737:. Retrieved
719:
691:. Retrieved
686:
650:
644:
625:
619:
607:. Retrieved
603:the original
598:
589:
578:. Retrieved
571:the original
561:
549:. Retrieved
545:the original
540:
531:
511:
478:Central Line
474:Western Line
467:
437:
420:
416:
409:
403:
401:
397:
381:
372:
367:many reasons
364:
358:
354:
341:
323:
312:
294:
285:
282:
275:
268:
265:
261:
240:
220:
212:
209:
206:
203:
200:
196:
187:
180:
176:
169:
165:
161:
144:
136:
128:How it works
116:
114:
111:
98:British Rail
95:
79:
73:
71:
67:
52:
35:
31:
29:
1784:Switzerland
1759:New Zealand
1754:Netherlands
1460:Slide fence
1213:Lever frame
1011:31 December
333:Limitations
319:buffer stop
82:train stops
1809:Categories
1692:By country
1475:Train stop
1440:RS4 Codici
1198:Block post
902:24 October
878:2017-02-07
771:2017-02-06
693:2013-03-18
580:2017-02-06
524:References
460:, without
407:solution.
365:There are
309:Variations
1699:Australia
1552:AŽD Praha
1511:Crossbuck
1415:Crocodile
1051:1 January
987:Uff, John
971:1 January
918:Uff, John
846:1 January
818:Uff, John
799:4 October
739:1 January
711:Uff, John
551:1 January
458:Australia
102:Railtrack
46:, and in
1789:Thailand
1597:Safetran
1587:Magnetic
1572:Griswold
1521:E-signal
484:See also
454:Victoria
302:derailer
133:Overview
48:Victoria
1734:Germany
1724:Finland
1709:Belgium
1704:Bavaria
1607:Siemens
1582:Hitachi
1557:Federal
1542:Adtranz
1445:SelTrac
1292:Treadle
1238:Signals
609:31 July
446:, with
244:overlap
181:When a
92:History
77:speed.
38:) is a
1779:Sweden
1774:Poland
1769:Norway
1739:Greece
1729:France
1714:Canada
1617:Thales
1547:Alstom
1516:Wigwag
1395:EBICAB
1365:Balise
1042:
1002:
962:
837:
730:
657:
632:
412:Purley
1749:Japan
1744:Italy
1719:China
1653:AREMA
1602:Saxby
1455:SACEM
1400:IIATS
1325:ATACS
1170:Token
1036:(PDF)
996:(PDF)
956:(PDF)
929:(PDF)
896:(PDF)
872:(PDF)
865:(PDF)
831:(PDF)
793:(PDF)
765:(PDF)
724:(PDF)
683:(PDF)
574:(PDF)
516:12%g.
503:Notes
338:Speed
74:TPWS+
1673:IRSE
1668:HMRI
1577:Hall
1320:ASFA
1315:ALSN
1053:2024
1040:ISBN
1013:2023
1000:ISBN
973:2024
960:ISBN
904:2023
848:2024
835:ISBN
801:2017
741:2024
728:ISBN
655:ISBN
630:ISBN
611:2019
553:2024
476:and
442:The
426:and
345:HSTs
326:SPAD
276:The
36:TPWS
30:The
1683:UIC
1663:FRA
1658:ERA
1648:AAR
1567:GRS
1071:at
462:AWS
448:AWS
278:AWS
172:kHz
1811::
941:^
931:.
924:.
920:;
820:;
809:^
749:^
713:;
702:^
685:.
669:^
597:.
539:.
480:.
456:,
124:.
1106:e
1099:t
1092:v
1055:.
1015:.
975:.
906:.
881:.
850:.
803:.
774:.
743:.
696:.
663:.
638:.
613:.
583:.
555:.
34:(
20:)
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