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Post by Deleted on Dec 6, 2010 20:11:53 GMT
tried a search, came up with nowt so...
What happens if a train in ATO mode takes a wrong turn, say at North Acton? Is such an occurance even possible?
Does the train know for example it's meant to be a Ruislip, and thus automagically refuses the Ealing Road? Or is some kind of driver intervention necessary? Can you even set the wrong road for a train on the signalling system (which AFAIUI is computerised and highly sophisticated)
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Post by londonstuff on Dec 6, 2010 20:15:13 GMT
tried a search, came up with nowt so... What happens if a train in ATO mode takes a wrong turn, say at North Acton? Is such an occurance even possible? Does the train know for example it's meant to be a Ruislip, and thus automagically refuses the Ealing Road? Or is some kind of driver intervention necessary? Can you even set the wrong road for a train on the signalling system (which AFAIUI is computerised and highly sophisticated) Not directly related but I heard one driver tell another that a Victoria line train had SPADded earlier that morning - so perhaps it is possible? |
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Post by Deleted on Dec 6, 2010 20:44:16 GMT
tried a search, came up with nowt so... What happens if a train in ATO mode takes a wrong turn, say at North Acton? Is such an occurance even possible? Does the train know for example it's meant to be a Ruislip, and thus automagically refuses the Ealing Road? Or is some kind of driver intervention necessary? Can you even set the wrong road for a train on the signalling system (which AFAIUI is computerised and highly sophisticated) Not directly related but I heard one driver tell another that a Victoria line train had SPADded earlier that morning - so perhaps it is possible? That would be a code trip, caused by a signal failure. At the OP, you would get a frequency out of order and code trip. www.davros.org/rail/signalling/articles/central.htmlIt would be possible to wrong'un, but like I said, you'd get an out of sequence frequency. |
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Post by Deleted on Dec 6, 2010 20:46:36 GMT
The Central signalling is intelligent, but not that good! If the wrong stick is given which has happened, it is normally down to the control centre system getting it wrong or a timetable error. The train will be updated with the revised destination at the station over the PAC system, and will know where it is going, albeit the wrong way. The only thing to stop it from taking the wrong stick is the driver.
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Post by Deleted on Dec 6, 2010 20:48:57 GMT
Not directly related but I heard one driver tell another that a Victoria line train had SPADded earlier that morning - so perhaps it is possible? That would be a code trip, caused by a signal failure. At the OP, you would get a frequency out of order and code trip. www.davros.org/rail/signalling/articles/central.htmlIt would be possible to wrong'un, but like I said, you'd get an out of sequence frequency. Scratch that thought, I'm not thinking straight tonight. You wouldn't get code tripped on a wrong'un as the ATP system would be expecting that route, unless there was a points failure, but the interlocking would prevent a train going over them. |
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Tom
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Post by Tom on Dec 7, 2010 23:57:21 GMT
tried a search, came up with nowt so... What happens if a train in ATO mode takes a wrong turn, say at North Acton? Is such an occurance even possible? Yes it can, and I've been on a train that's done it. The ATO data for all possible routes is uploaded to a train, regardless of the train's destination. |
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Post by Tom on Dec 8, 2010 0:03:46 GMT
That would be a code trip, caused by a signal failure. At the OP, you would get a frequency out of order and code trip. www.davros.org/rail/signalling/articles/central.htmlIt would be possible to wrong'un, but like I said, you'd get an out of sequence frequency. Scratch that thought, I'm not thinking straight tonight. You wouldn't get code tripped on a wrong'un as the ATP system would be expecting that route, unless there was a points failure, but the interlocking would prevent a train going over them. Correct, the train would suffer no adverse effect. As the article states, around points carrier frequency f4 is used, which allows any other carrier frequency to appear afterwards. What actually happens is the track circuit over the points has two carrier frequencies allocated, one from the normal range for the nominal straight route, and f4 for the divergence. The appropriate frequency is then selected by the lie of the points. The ATO data has a list of all the track circuit boundaries and their relevant carrier frequencies and this is used to identify which route the train takes and therefore what data to look at. |
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Phil
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Post by Phil on Dec 8, 2010 7:57:03 GMT
What actually happens is the track circuit over the points has two carrier frequencies allocated, one from the normal range for the nominal straight route, and f4 for the divergence. The appropriate frequency is then selected by the lie of the points. The ATO data has a list of all the track circuit boundaries and their relevant carrier frequencies and this is used to identify which route the train takes and therefore what data to look at. So are you saying the lie of the points is set by the signalling system alone? And hence it's not the train that tells the points which way to set? In other words, does the train not 'read' (or indeed 'write to') the set of the points at all in the way it 'reads' stations etc.? |
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Post by Deleted on Dec 8, 2010 8:04:56 GMT
What actually happens is the track circuit over the points has two carrier frequencies allocated, one from the normal range for the nominal straight route, and f4 for the divergence. The appropriate frequency is then selected by the lie of the points. The ATO data has a list of all the track circuit boundaries and their relevant carrier frequencies and this is used to identify which route the train takes and therefore what data to look at. So are you saying the lie of the points is set by the signalling system alone? And hence it's not the train that tells the points which way to set? In other words, does the train not 'read' (or indeed 'write to') the set of the points at all in the way it 'reads' stations etc.? The PAC at each station tells it CSDE and information about the run to the next station, and possibly a skip point. The signalling system should know the train descriptor and where it should be. Of course, if you get a train leaving out of turn at North Acton, that could cause some problems. The points are after the station, yes? |
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Post by auxsetreq on Dec 8, 2010 12:18:53 GMT
As far as I understand, and use it......The path of every timetabled train is set/programmed into whatever timetable is running on that day. Anything else is dealt with by the signalling desk at Wood Lane. So if the L/C wants a certain train to go onto Snaresbrook instead of Wanstead he does whatever with his mouse to send it on it's way. Or if an additional train is required to run like a stock move, Wood Lane create a path for it.............
The PACs relay information to and from Wood Lane from each train. Data sent includes PTI - load weigh, defects, unit numbers, and so on. Data picked up includes ATO map data, DTS text messages, CDSE, ATO skip, Door inhibit and some other stuff I can't think of.............AFAIK the trains don't link into the signalling system directly.........unless the boffins know different..............
At a diverging junction the train up loads four lots of map data - two primary, two secondary for each route. So if the L/C decides to send a train to a different destination the info is in it's memory buffer. As it crosses over the points it dumps the route it doesn't need. So, it's up to the L/C to tell the driver that the train's destination is being changed and it's up the the driver to check the lie of the points and route indicator arrow. If the driver hasn't been told what is going on ( not unusual ) and he gets what to him is the wrong route, then he must contact the L/C to confirm his destination. Ultimately it's the driver who gets it if he accepts the wrong route............Ultimately it's the drivers who get the blame for everything. Like going on strike when they're not on strike and being the cause of climate change according to the ES.
That's what I was told on the ATP ATO courses some years ago, some of it may of changed.............I know nothing of boffin frequencies except the "keep this frequency clear" rap and 95.8 for Capital FM and 97.3 for LBC - AKA the Daily Mail on air............
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Post by superteacher on Dec 8, 2010 12:57:53 GMT
As far as I understand, and use it......The path of every timetabled train is set/programmed into whatever timetable is running on that day. Anything else is dealt with by the signalling desk at Wood Lane. So if the L/C wants a certain train to go onto Snaresbrook instead of Wanstead he does whatever with his mouse to send it on it's way. Or if an additional train is required to run like a stock move, Wood Lane create a path for it............. The PACs relay information to and from Wood Lane from each train. Data sent includes PTI - load weigh, defects, unit numbers, and so on. Data picked up includes ATO map data, DTS text messages, CDSE, ATO skip, Door inhibit and some other stuff I can't think of.............AFAIK the trains don't link into the signalling system directly.........unless the boffins know different.............. At a diverging junction the train up loads four lots of map data - two primary, two secondary for each route. So if the L/C decides to send a train to a different destination the info is in it's memory buffer. As it crosses over the points it dumps the route it doesn't need. So, it's up to the L/C to tell the driver that the train's destination is being changed and it's up the the driver to check the lie of the points and route indicator arrow. If the driver hasn't been told what is going on ( not unusual ) and he gets what to him is the wrong route, then he must contact the L/C to confirm his destination. Ultimately it's the driver who gets it he accepts the wrong route............Ultimately it's the drivers who get the blame for everything. Like going on strike when they're not on strike and being the cause of climate change according to the ES. That's what I was told on the ATP ATO courses some years ago, some of it may of changed.............I know nothing of boffin frequencies except the "keep this frequency clear" rap and 95.8 for Capital FM and 97.3 for LBC - AKA the Daily Mail on air............ However at North Acton, the junction isome way past the station, and I'm not sure if the signal is visible from the end of the westbound platform. At Leytonstone, the diverging signal is also the station starter, so it's easy there. If a train is running in ATO and the driver spots a wrong stick, am I right in thinking that taking the train out of ATO will cause an emergency stop - if so, that's hardly a good solution! |
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Post by auxsetreq on Dec 8, 2010 15:55:23 GMT
Yes, it's way past the station but it can still be seen - red or green. The indicator arrow is a little more difficult to make out though. Taking a train out of ATO at speed brings the train to a halt with an emergency brake, but it's not that rough a stop compared to slamming on the brakes due to loss of door proving on take off, which is all to common............ www.youtube.com/user/Auxsetrequired?feature=mhum |
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Post by superteacher on Dec 8, 2010 19:12:21 GMT
I thought the jerking when the door circuits are not proved is merely the motors cutting out, and not braking. I'm thinkimg this because ofter the jerk, the train coasts rather than comes to a stop. It's a bit like pulling away in a car in first gear, then taking your foot off the accelerator.
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Post by auxsetreq on Dec 8, 2010 23:12:35 GMT
I thought the jerking when the door circuits are not proved is merely the motors cutting out, and not braking. I'm thinkimg this because ofter the jerk, the train coasts rather than comes to a stop. It's a bit like pulling away in a car in first gear, then taking your foot off the accelerator. That's right, but after loss of door proving the rules are that the driver applies an emergency brake immediately. Usually that occurs after several jerks, so to speak, but technically it should be on the first occasion. Reasons being, it's loss of door proving which speaks for itself, and the ATO data may of become corrupted resulting in an overun at the next platform. After an ATO interruption it means the train is driven manually to the next PAC. The coasting is some or all of the units not motoring as the jerking affects the traction logic. So the train has to be stopped and another attempt to get the train moving normally is made. |
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Post by superteacher on Dec 8, 2010 23:23:58 GMT
I thought the jerking when the door circuits are not proved is merely the motors cutting out, and not braking. I'm thinkimg this because ofter the jerk, the train coasts rather than comes to a stop. It's a bit like pulling away in a car in first gear, then taking your foot off the accelerator. That's right, but after loss of door proving the rules are that the driver applies an emergency brake immediately. Usually that occurs after several jerks, so to speak, but technically it should be on the first occasion. Reasons being, it's loss of door proving which speaks for itself, and the ATO data may of become corrupted resulting in an overun at the next platform. After an ATO interruption it means the train is driven manually to the next PAC. The coasting is some or all of the units not motoring as the jerking affects the traction logic. So the train has to be stopped and another attempt to get the train moving normally is made. If you followed the rules to the letter and applied the emergency brake after every loss of door proving, the Central line peak service would disintegrate! The 1992 stock doors open too easily when leant upon. OK, only by an inch or so, but enough to break the circuit. |
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Tom
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Post by Tom on Dec 9, 2010 4:48:13 GMT
So are you saying the lie of the points is set by the signalling system alone? And hence it's not the train that tells the points which way to set? In other words, does the train not 'read' (or indeed 'write to') the set of the points at all in the way it 'reads' stations etc.? Yes, the lie of the points is set by the signalling system alone. The destination code entered into the train has no effect. The trains do read the point positions (and hence know where they are going) by the different carrier frequencies for different point positions |
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Post by metrolander on Dec 9, 2010 17:28:54 GMT
I know nothing of boffin frequencies except the "keep this frequency clear" rap and 95.8 for Capital FM and 97.3 for LBC - AKA the Daily Mail on air............ The Bomb The Bass reference is my favourite comment on here ever |
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