Paddington Station 24/7 - Channel 5

[richw]

Anybody notice the continuity error with the voice over?

Footage discussing 57605 at Long Rock, then voiceover said meanwhile at Reading (implying same day), and that was 57605 as well.

 

[co-tr-paul]

Reminder: SOME scenarios for this series (mainly maintainance) were mock for viewers excitement...... .

 

[GodAtum]

Reminder: SOME scenarios for this series (mainly maintainance) were mock for viewers excitement...... .

Like today's track circuit failure

 

[hexagon789]

Like today's track circuit failure

Talking of that, is there no way of operating in a platform with a track circuit failure? Couldn't you for instance caution trains in and out and have dispatchers give verbal communications to the signallers that the platform was occupied or not?

 

[bnm]

Talking of that, is there no way of operating in a platform with a track circuit failure? Couldn't you for instance caution trains in and out and have dispatchers give verbal communications to the signallers that the platform was occupied or not?

Three days to repair a TCF?

Engineering excellence.

 

[hexagon789]

Three days to repair a TCF?

Engineering excellence.

Well, it kept coming back online and then going back on the blink. I think they thought they'd fixed about 3 or 4 times in all only for it to fail again.

 

[Warwick]

Talking of that, is there no way of operating in a platform with a track circuit failure? Couldn't you for instance caution trains in and out and have dispatchers give verbal communications to the signallers that the platform was occupied or not?

I believe that that's what used to happen but there seems to be a collective thought that it's better to stop everything nowadays. If the track circuiting electricity is not working does it mean that the points won't work either so a train cannot be put into the relevant platform?

 

[alxndr]

I believe that that's what used to happen but there seems to be a collective thought that it's better to stop everything nowadays. If the track circuiting electricity is not working does it mean that the points won't work either so a train cannot be put into the relevant platform?

Cautioning still happens, although maybe they're more reluctant to do it in platforms for some reason.

Depending on where the track is in relation to the points the points might have to be swung individually (rather than by calling a route over them) or might be locked up.

Sounds as though I'll find this week's either quite interesting (or infuriating)!

 

[edwin_m]

I believe that that's what used to happen but there seems to be a collective thought that it's better to stop everything nowadays. If the track circuiting electricity is not working does it mean that the points won't work either so a train cannot be put into the relevant platform?

The electricity was working normally so there's no reason to think that the power supply to points etc was defective. The problem, which is typical of track circuits, was that there was a conductive area allowing the current to leak between the rails and the ground. After at least one other thing was fixed this was traced to worn insulating pads under the rails, which literally required the rail to be lifted out section by section so they could be replaced. One does have to wonder though whether this shouldn't have been picked up earlier and fixed before it became a problem, especially after deterioration of the timbers supporting the platform rails led to a derailment on a previous series.

It would be possible to talk trains into the platform but this would involve each train for that platform stopping at the last signal on the approach to the station to receive instruction to pass it at danger. This would probably be more disruptive to other trains than the loss of a platform, creates some safety risk in itself, and would also have prevented anyone being on the track to try to fix the problem.

 

[GodAtum]

The electricity was working normally so there's no reason to think that the power supply to points etc was defective. The problem, which is typical of track circuits, was that there was a conductive area allowing the current to leak between the rails and the ground. After at least one other thing was fixed this was traced to worn insulating pads under the rails, which literally required the rail to be lifted out section by section so they could be replaced. One does have to wonder though whether this shouldn't have been picked up earlier and fixed before it became a problem, especially after deterioration of the timbers supporting the platform rails led to a derailment on a previous series.

In hindsight a failure of the insulating pads under the rails seems very obvious to non-engineering people like me. They would have been the 1st thing I would have checked.

 

[hexagon789]

I believe that that's what used to happen but there seems to be a collective thought that it's better to stop everything nowadays. If the track circuiting electricity is not working does it mean that the points won't work either so a train cannot be put into the relevant platform?

Just seemed as though if cautioning were permitted surely it would be better to run in/out at reduced speed rather than not use the platform at all.

 

[talldave]

Well, it kept coming back online and then going back on the blink. I think they thought they'd fixed about 3 or 4 times in all only for it to fail again.

That's the disappointing aspect - until day 3 they hadn't found a reason, just discovered that tinkering around seemed to make the problem go away.

As a techie, I'd like to hear more background though. What's the MTBF of the insulators? Should they have been replaced before they failed? If platform 5's are knackered, will all other platforms' insulators be inspected?

To the layman, it appears that everything's left to deteriorate until it breaks and then it's patched up, rather than being pro-actively inspected & renewed on a specific schedule. I'm sure that's not the case, but the programme portrays things that way.

And as for protecting analogue electronics from p155 and **** with a few mats........ I cringe!

 

[hexagon789]

That's the disappointing aspect - until day 3 they hadn't found a reason, just discovered that tinkering around seemed to make the problem go away.

As a techie, I'd like to hear more background though. What's the MTBF of the insulators? Should they have been replaced before they failed? If platform 5's are knackered, will all other platforms' insulators be inspected?

To the layman, it appears that everything's left to deteriorate until it breaks and then it's patched up, rather than being pro-actively inspected & renewed on a specific schedule. I'm sure that's not the case, but the programme portrays things that way.

And as for protecting analogue electronics from p155 and **** with a few mats........ I cringe!

I know, the whole toilet waste collection mats made me uncomfortable enough in the last series, and now we see them again! Thankfully not as much though.

I agree, you'd think that after the second failure they'd do a far more thorough check, though I suppose they must be under considerable pressure to re-open the platform ASAP.

 

[edwin_m]

I think the problem here is that most of the insulating pad is under the rail so can't be seen unless the rail is lifted, so they are probably only checked if they've checked everything first. I wonder if they could use some kind of current transducer around the rail to see where the track circuit current reduces and therefore where the electricity is "leaking"?

 

[GB]

In hindsight a failure of the insulating pads under the rails seems very obvious to non-engineering people like me. They would have been the 1st thing I would have checked.

Who needs experience, degrees and competencies when we have RUK!

 

[Mojo]

In hindsight a failure of the insulating pads under the rails seems very obvious to non-engineering people like me. They would have been the 1st thing I would have checked.

Good job you're not in charge of checking then, as that isn't a sensible thing to be looking for!

 

[alxndr]

Finally been able to watch it myself (only just come on Demand 5 this afternoon), and found a couple of bits quite strange/incorrect.

• Voiceover was discussing voltages while the images was of someone using a shunt box (which is clipped between the rails with a variable resistor in the middle, allowing a measurement to be taken of "how much" of a short is needed to pick and drop the track, and has nothing to do with voltages).
• Continuity seems all off. It was intermittent and they were investigating, then it went "hard down" and they seemed to stop. The best time to look into something is when it's consistently failed. Stopping at all, especially when they're still keeping it out of use seems quite strange to me too, unless there were more pressing issues elsewhere/shift change with lack of competancy.
• Talking about a "circuit box". I can understand dumbing things down, but I'm not sure what that was supposed to be, perhaps the loc?
• "Route control have narrowed it down..." They'll need a good pair of binoculars to narrow anything down from 77miles away!
• The mats must make it more difficult, but it is a bit surprising that they didn't properly examine the track earlier before ripping apart the IRJ.
• I would have thought that the cautioning of trains in the Bourton area would have been because of the thing which may have been struck, rather than because the MOM was about. Being trackside in the dark in 125mph areas is normal.

I wonder if they could use some kind of current transducer around the rail to see where the track circuit current reduces and therefore where the electricity is "leaking"?

These do exist (Rocoil) but only work on AC track circuits. The presence of the IRJ suggests that this may have been a DC track circuit, on which they're useless.

The other option would be a rail clip insulation tester/K9/sweeper. I can't find a photo of one of these, but they're a box on a stick that's pushed along the rail, with metal brushes hanging off the side. If there's a circuit formed between the box sat on the top of the rail and the hanging brushes that touch the clips then it beeps. I'm not sure whether this would work with those clips though, and they are very temperamental, especially in the damp.

 

[yorksrob]

What are channel 5 playing at ? The latest episode hasn't been available on their website for the past two days !

 

[The_Engineer]

Talking of that, is there no way of operating in a platform with a track circuit failure?

Given that modern signalling systems use software-controlled route setting, it should not be possible to set a route (and therefore points) into a platform that is giving an occupied indictaion. When you think about it, that's an absolute no-no for signalling systems.

Under older systems of signalling it may have been possible to set up the route and get a train to pass a signal at danger, but even then (in ye olden days) I think that would have needed some very stringent procedure to allow that to happen.

 

[hexagon789]

Given that modern signalling systems use software-controlled route setting, it should not be possible to set a route (and therefore points) into a platform that is giving an occupied indictaion. When you think about it, that's an absolute no-no for signalling systems.

Under older systems of signalling it may have been possible to set up the route and get a train to pass a signal at danger, but even then (in ye olden days) I think that would have needed some very stringent procedure to allow that to happen.

Fair enough, I can understand why it isn't possible/done, it just seems a bit inflexible.

 

[edwin_m]

Given that modern signalling systems use software-controlled route setting, it should not be possible to set a route (and therefore points) into a platform that is giving an occupied indictaion. When you think about it, that's an absolute no-no for signalling systems.

Under older systems of signalling it may have been possible to set up the route and get a train to pass a signal at danger, but even then (in ye olden days) I think that would have needed some very stringent procedure to allow that to happen.

You could set the route but the signal wouldn't clear, just as you can overset for a following train before the preceding one has left the route (as long as it's passed over any points that need to change). Or if the platform has several track circuits and the first one is clear you would get a subsidiary aspect. I don't think automatic route setting systems would set a route if there was an unexpected occupied track circuit.

I don't remember if the rules would require the signaller to key points manually if they wanted to talk a train into a platform the signalling thought was (fully) occupied.

 

[SamYeager]

Given that modern signalling systems use software-controlled route setting, it should not be possible to set a route (and therefore points) into a platform that is giving an occupied indictaion. When you think about it, that's an absolute no-no for signalling systems.

How do signallers allow more than one train into the same platform then or is just a matter of allowing the driver to pass a red?

 

[hexagon789]

How do signallers allow more than one train into the same platform then or is just a matter of allowing the driver to pass a red?

Calling-on or position lights which allow drivers to proceed under caution into occupied sections such as platforms.

 

[edwin_m]

The position light or subsidiary aspect tells the driver to proceed but to be able to stop short of any obstruction, in this case a platform with a train at the far end.

Some stations have multiple track circuits in the platforms and even "measuring tracks" on the approach to the protecting signal so that the subsidiary route will only clear if the approaching train is shorter than the space in the platform. I was involved in the original Automatic Route Setting at Liverpool Street and that was programmed not to send a train into an occupied platform - the signaller could set the route manually.

 

[rebmcr]

only just come on Demand 5 this afternoon

Oh good.

 

[ChiefPlanner]

The position light or subsidiary aspect tells the driver to proceed but to be able to stop short of any obstruction, in this case a platform with a train at the far end.

Some stations have multiple track circuits in the platforms and even "measuring tracks" on the approach to the protecting signal so that the subsidiary route will only clear if the approaching train is shorter than the space in the platform. I was involved in the original Automatic Route Setting at Liverpool Street and that was programmed not to send a train into an occupied platform - the signaller could set the route manually.

The well known Lime Street Control - with measured track circuit berths. Railway "A level knowledge" - an excellent measure.

 

[Nippy]

Incidentally, Lime Street controls were removed from Paddington at Christmas, the system now relies on us knowing there's room for the second (or third) train. We are having the same issue on Platfrom 4 at the moment, intermittent fault so T/C disconnected and trains given the sub in once confirmed the last train departed by checking the CCTV screens on the SSM desk. It is waiting contractors to remove the poo pads so the S&T can investigate. I personally can't wait until the HSTs finish at Paddington, the state of the tracks there is disgusting.

 

[D1009]

The well known Lime Street Control - with measured track circuit berths. Railway "A level knowledge" - an excellent measure.

It was OK until train lengths became less standardised. We discovered this at Kings Cross where the Lime Street Control prevented certain combinations of stock sharing a platform even though there was room in practice.

 

[Nick Philpott]

Like today's track circuit failure

Obviously never tried to find a fault on a track circuit

 

[SamYeager]

Presumably those travellers were getting paid to get rid of other people's junk knowing that NR was going to end up with the bill.