intermittent and continuous ATP 101119 - irse.nl

More documents

Recommendations

Info

after a trip cock has been tripped, which not only is time consuming, but requires thedriver to leave his cab and walk along the track which immediately exposes him tosignificant health and safety risks, not the least of which is being hit by another train.Whilst such systems are generally regarded as fail-safe by the inherentmechanical properties of the design and equipment, reports of wrong side failuresexist, demonstrating that these systems, as virtually all signaling systems, depend onregular (preventative) maintenance and inspections to maintain their safety levels.Intermittent Contactless SystemsPermanent Magnet Systems.The next evolutionary step for ATP systems was to replace the mechanicalinteraction between track and train by a “transmission system” based on magneticcoupling. A permanent magnet operates an on-board relay when the train is passing,which again opens a brake valve so that the brake is activated. If the signal is not atstop, a coil around the permanent magnet is powered and cancels the magnetic fluxof the permanent magnet. When the train passes such a signal, there is no effect onthe brake system. The system already shows a basic safety principle of railwaysignalling, a design based on the high probability of a reaction to the safe side in thecase of a defect or malfunction we now call fail safety. In case of any failure of theactive electrical part, the train would be stopped.Magnetic Trip StopA similar principle is used in the British Automatic Warning System AWS, here acombination of different polarisation of magnetic fields of a permanent magnet andan electromagnet is used to either warn the driver, or simply to indicate that a magnethas been passed. In case of a warning, the driver has to acknowledge the warningwithin four seconds.11
AWS MagnetsAn electrical transmission by a physical contact between a trackside contact railand a trainborne brush is used in the French and Belgian “crocodile” system.Depending on the polarity of the received voltage on board, the driver is also eitherwarned or informed.AWS on-board principleAC Systems.AC intermittent systems are usually based on the principle of installingpermanent magnets in the track, the field of which can be cancelled by an AC signalwhich is fed through additional coils when the signal shows a proceed aspect.Examples of such systems include the German Indusi system, the Glasgow Subway[26] CTS system etc.12
Page 1 and 2: An Introduction to Intermittent and
Page 3 and 4: level the degree of safety is also
Page 5 and 6: affordable at all. In literature, e
Page 7 and 8: contradiction stems from the fact t
Page 9 and 10: GWML en Chiltern lines indicate tha
Page 11: Technology of ATP/ATC systemsThis c
Page 15 and 16: Positioning of Indusi magnetsIn the
Page 17 and 18: end was traditionally done means of
Page 19 and 20: Train-borne System Architecture and
Page 21 and 22: Some parts of the train control sys
Page 23 and 24: fairly rare occurrence and, when th
Page 25 and 26: Examplesof ATP/ATC systemsLZB As Ex
Page 27 and 28: LZB data flowThe data available fro
Page 29 and 30: • signal aspects• point setting
Page 31 and 32: SELCAB transmissionThe number of se
Page 33 and 34: The first curve (indication curve)
Page 35 and 36: equired to reset the train-carried
Page 37 and 38: tests on sites located in different
Page 39 and 40: Current European ATP systemsThe fol
Page 41 and 42: • Level 2 is also based on conven
Page 43 and 44: signal information, it has to be ac
Page 45 and 46: Euroloop locationsLevel 2 would be
Page 47 and 48: information can be processed by the
Page 49 and 50: Ensuring safe and reliable operatio
Page 51 and 52: References and Bibliography1 ATP -
Page 53: Table 2 Numbers of existing ATP equ

intermittent and continuous ATP 101119 - irse.nl

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?