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Author Topic: Thames Valley signalling problems - big delays - July 2014  (Read 88277 times)
ChrisB
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« Reply #90 on: July 18, 2014, 12:00:12 »

Cable fault, wasn't it?
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broadgage
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« Reply #91 on: July 18, 2014, 12:27:10 »

And another lightening strike twixt Beaconsfield & Gerrards Cross on Chiltern

I don't now why, but signalling equipment seems to be very susceptible to lightning nowadays.  I'm sure it never use to be.

Old signalling that consisted of mechanical semaphore signals, lit by oil lamps was immune to lightning damage except in the rare case of a direct strike on a signal box, and even that affected only a short length of line and could be worked around. Track circuits if used would be powered by local batteries.
Telegraph  communication with adjacent boxes was required for block working, but even if this failed a limited service could be run.
Mains electricity was not essiential, and in some cases was not even provided.


Modern signalling control centres control large areas and a single lightning strike, fire, cable theft etc can disable signals over a wide area.
As fewer and fewer ever larger control rooms take over ever larger parts of the network I suspect that large scale failures will become more numerous.
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A proper intercity train has a minimum of 8 coaches, gangwayed throughout, with first at one end, and a full sized buffet car between first and standard.
It has space for cycles, surfboards,luggage etc.
A 5 car DMU (Diesel Multiple Unit) is not a proper inter-city train. The 5+5 and 9 car DMUs are almost as bad.
stuving
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« Reply #92 on: July 18, 2014, 13:26:44 »

Modern signalling control centres control large areas and a single lightning strike, fire, cable theft etc can disable signals over a wide area.
As fewer and fewer ever larger control rooms take over ever larger parts of the network I suspect that large scale failures will become more numerous.

As signalling becomes a matter of computers - down to very small ones - sending data about, things ought to begin improving. It's true that light bulbs are more vulnerable than steel cables, and electronics still more so, but modern electronics has some protection built in at chip level and where wires go out into the world. More importantly, the longer-distance communications can be done via optical fibres - which are nearly immune to lightning - and using multiple alternative routes and IP networking. And if an electronics box is damaged, it's a standard module that can be swapped and customised for its task by a download. So the time and effort for repair come down sharply too.

I think all of these benefits should come in the GWML (Great Western Main Line) resignalling now underway, though not to the rest of the network until much later.
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« Reply #93 on: July 18, 2014, 17:12:06 »

And another lightening strike twixt Beaconsfield & Gerrards Cross on Chiltern

Arrrrrrrrrrrrrrrrrrrrgh Estate Agent speak ......... do you between Beaconsfield & Gerrards Cross on Chiltern

And another lightening strike twixt Beaconsfield & Gerrards Cross on Chiltern

I don't now why, but signalling equipment seems to be very susceptible to lightning nowadays.  I'm sure it never use to be.

Old signalling that consisted of mechanical semaphore signals, lit by oil lamps was immune to lightning damage except in the rare case of a direct strike on a signal box, and even that affected only a short length of line and could be worked around. Track circuits if used would be powered by local batteries.
Telegraph  communication with adjacent boxes was required for block working, but even if this failed a limited service could be run.
Mains electricity was not essiential, and in some cases was not even provided.


Modern signalling control centres control large areas and a single lightning strike, fire, cable theft etc can disable signals over a wide area.
As fewer and fewer ever larger control rooms take over ever larger parts of the network I suspect that large scale failures will become more numerous.

Railways are very susceptible to direct lightning strikes due to the large amount of highly conductive material that runs for miles and indirect strikes.

While fibre optics does give a high degree of immunity to lightning there is a lot of local cabling from the fibre nodes to the signalling equipment on track, even if a fibre was taken direct to the remote devices (which it is not) there is still the power supplies that can get taken out by.

Even electrification is not immune to lightning dc rectifiers and track circuit breakers can flash over and 25kV track circuit breakers have been known to flash over as well.
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Starship just experienced what we call a rapid unscheduled disassembly, or a RUD, during ascent,”
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« Reply #94 on: July 21, 2014, 07:20:50 »

Old signalling that consisted of mechanical semaphore signals, lit by oil lamps was immune to lightning damage except in the rare case of a direct strike on a signal box, and even that affected only a short length of line and could be worked around. Track circuits if used would be powered by local batteries.
Telegraph  communication with adjacent boxes was required for block working, but even if this failed a limited service could be run.
Mains electricity was not essiential, and in some cases was not even provided.


Modern signalling control centres control large areas and a single lightning strike, fire, cable theft etc can disable signals over a wide area.
As fewer and fewer ever larger control rooms take over ever larger parts of the network I suspect that large scale failures will become more numerous.

I read this post last week feeling rather smug - we have heritage signalling in this part of the world.

Alas, today it's gone into meltdown. I arrived at Foregate St to catch the 07:00 to B'ham only to find the 06:14 HST (High Speed Train) to Padd'n still sitting in the platform.

Fortunately the unusual track layout at FS meant that the 07:00 could be sent through platform 2 so as to avoid Shrub Hill.

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stuving
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« Reply #95 on: July 21, 2014, 09:04:46 »

Here are a few broader comments about last Monday (14th). I was going to go from Wokingham, via Reading to join someone, then via Paddington to Ilford. I was a bit late in checking so when I found out that "sorry dear, trains are off" it meant a quick call to redirect my companion to get the 10:42 Waterloo train, which I joined at WKM.

There was no information about disruption at Wokingham - no signs, or announcements, or anything on the CIS (Customer Information System). Since a lot of people go via RDG(resolve)-PAD» (Paddington (London) - next trains) this seems odd. If I'd set off towards Reading and then found I had to come back again I would have been really cuniculus infelicissimus. "Not our railway" doesn't really apply - it is, and SWT (South West Trains) sell tickets for it. The train was full, of course, and I had to stand. That was no surprise to us, but for a lot of those trying to board it along the way it was - again no information.

I did think about getting off at Staines and getting the next train from Windsor, trading minutes for being less crowded. In the end this looked more hassle than it was worth, since there was a lad with a bike in the way. He was being very good, holding it stood on its back wheel so it took up least space, but it was hardly a good idea. If we had stopped sharply it could have been quite messy. If cycles are not allowed on peak trains, and this one was far more crowded, I presume he could have been told to get off. Mind you, at Feltham space was found for a wheelchair, which seemed an odd choice of train. Of course that had to go on its booked service, and carriage, to get the ramp there for him to get off.

There could have been an announcement suggesting that people change trains at Staines, but there was none at all. Looking at the people waiting to get on, they had not been advised that they could pick another train. Of course I have no idea how many people would actually choose to be 15 minutes later just to be almost certain to get a seat.

Given the timescales, it is probably just not feasible for SWT to adapt their service to cope with displaced passengers. But they might make an effort to help their own customers, as well as the FGW (First Great Western) refugees, avoid the worst consequences. Pontius Pilate, where is thy railway?
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« Reply #96 on: July 24, 2014, 16:27:58 »

It looks like Twyford is having a day off and so the line down to Basingstoke has decided to break instead:

Cancellations to services at Reading
Owing to signalling problems at Reading fewer trains are able to run on Basingstoke bound lines.
Impact:  Train services running to and from this station may be cancelled or delayed by up to 10 mins at short notice. An estimate for the resumption of normal services will be provided as soon as the problem has been fully assessed.
Customer Advice:First Great Western Trains from Reading to Basingstoke will be running hourly instead of half-hourly.
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Red Squirrel
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« Reply #97 on: July 24, 2014, 16:49:01 »

cuniculus infelicissimus

Never one to be distracted by anything tangential - SQUIRREL! - I had to whizz that one through the Google TranslatyThing TM(resolve).

Interestingly 'cuniculus infelicissimus' translates as 'The mine, the poor' - after which I felt none the wiser, and not much better-informed.

Then I realised there may be some advantage in trying 'cuniculus felicissimus' - and lo! Out popped 'happy rabbit', as though from a hat. Now I understand what you mean; as is often the case with great art, it was worth a little investment to try to understand.
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Things take longer to happen than you think they will, and then they happen faster than you thought they could.
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« Reply #98 on: July 25, 2014, 16:24:56 »

Lightning again today:
Quote
Cancellations to services between Reading and Slough
Owing to lightning having damaged equipment between Reading and Slough fewer trains are able to run on all lines.
Impact:
Train services running to and from these stations may be cancelled or delayed at short notice. An estimate for the resumption of normal services will be provided as soon as the problem has been fully assessed.
Customer Advice:
Chiltern Railways services are conveying passengers via any reasonable route until further notice.
Cross Country services are conveying passengers between Oxford and Banbury in both directions until further notice.
Underground services are conveying passengers via any reasonable route until further notice.
First Berkshire Buses 1B & 2 Slough (Bus Station) - Burnham, First Berkshire Bus 75 Maidenhead - Taplow - Burnham - Slough (Bus Station) - Langley and First Berkshire Bus 76 Burnham - Slough (Bus Station) - Langley services are conveying passengers via any reasonable route until further notice.
Show Further Information
Last Updated :25/07/2014 16:05
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sorch
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« Reply #99 on: July 25, 2014, 16:35:48 »

At Paddington now, things are pretty rammed. I don't know if this is normal for 4pm on a Friday.

I like how they're using a guy on a totally inadequate megaphone to give some information, instead of the PA (Public Address) system that would cover the entire station and let more than about 5 people hear. All I could make out is that ticket restrictions have been lifted.
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a-driver
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« Reply #100 on: July 25, 2014, 16:44:02 »

At Paddington now, things are pretty rammed. I don't know if this is normal for 4pm on a Friday.

I like how they're using a guy on a totally inadequate megaphone to give some information, instead of the PA (Public Address) system that would cover the entire station and let more than about 5 people hear. All I could make out is that ticket restrictions have been lifted.

I was at Twyford at the time of the lightning strike.  We had two or three flashes of lightning and a bit of thunder and suddenly this massive strike accompanied by a deafening clap of thunder.  Very frightening, I even ducked for some reason!

Believe SouthWest Trains are also suffering the effects of a lightning strike.
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stuving
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« Reply #101 on: July 25, 2014, 16:50:03 »

Believe SouthWest Trains are also suffering the effects of a lightning strike.

Yes, at Surbiton. Currently, their alerts page (and National Rail) says:
Quote
Trains between London Waterloo and Exeter/Salisbury will only run between Basingstoke and Exeter/Salisbury - Customers will need to take the first service to Basingstoke and change there to complete your journey, please be advised that connections cannot be guaranteed.
...
First Great Western will accept customers on reasonable routes.

Oh dear.

I note that FGW (First Great Western) do not list SWT (South West Trains) as an alternative from Reading, though as far as I can see that is now running almost normally, though there were some effects of the problems at Waterloo.
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a-driver
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« Reply #102 on: July 25, 2014, 16:55:22 »

Believe SouthWest Trains are also suffering the effects of a lightning strike.

Yes, at Surbiton. Currently, their alerts page (and National Rail) says:
Quote
Trains between London Waterloo and Exeter/Salisbury will only run between Basingstoke and Exeter/Salisbury - Customers will need to take the first service to Basingstoke and change there to complete your journey, please be advised that connections cannot be guaranteed.
...
First Great Western will accept customers on reasonable routes.

Oh dear.

I note that FGW (First Great Western) do not list SWT (South West Trains) as an alternative from Reading, though as far as I can see that is now running almost normally, though there were some effects of the problems at Waterloo.

Guessing the storm must be heading West.  Surbiton was the location of the lightning strike for SWT
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sorch
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« Reply #103 on: July 25, 2014, 16:58:26 »

At Paddington now, things are pretty rammed. I don't know if this is normal for 4pm on a Friday.

I like how they're using a guy on a totally inadequate megaphone to give some information, instead of the PA (Public Address) system that would cover the entire station and let more than about 5 people hear. All I could make out is that ticket restrictions have been lifted.

I was at Twyford at the time of the lightning strike.  We had two or three flashes of lightning and a bit of thunder and suddenly this massive strike accompanied by a deafening clap of thunder.  Very frightening, I even ducked for some reason!

Believe SouthWest Trains are also suffering the effects of a lightning strike.


When did it strike / the signalling fell apart?

My train has left Paddington (fortunately didn't have to join the scrum) but it is wedged. I'm guessing there almost certainly will be huge delays passing through Twyford. We're currently on the main line around Southall.
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Timmer
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« Reply #104 on: July 25, 2014, 17:13:40 »

FGW (First Great Western) reporting on Twitter no HSS (High Speed Services) until the: 1803 to WoE then hourly, 1830 to Bristol/Weston Super Mare then hourly, 1845 to South Wales then hourly.
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