Thameslink core problems

[AM9]

There is but it can only be used to physically lock it ( during isolations or dragging a failed unit). When in service they are not locked down, only lowered.
--- old post above --- --- new post below ---


Shoes are permanently lowered on 319's, only 377's go up and down.

So given the dire consequences of a simple driver error or equipment failure, could anybody comment on my suggestion made in posts #19 & #22:

"Actually my point was that whether solid beam or knitting, the problem of the Snow Hill tunnel and the Smithfield sidings may be one of clearances...
If the wire/track was unenergised, it wouldn't need clearance above for 25kV. It would just be there to prevent the pantograph rising and hitting the roof of the tunnel.
It could actually be energised with a low voltage, e.g. 48VDC and any connection to it could be detected by the line side systems, thereby giving an opportunity to stop the driver proceeding."

Given the high cost of the Thameslink programme and the very high dependence on its smooth operation in the core when the full service starts, if such a measure was viable, the cost would be negligible compared with consequences like this.

 

[SpacePhoenix]

What keeps the pans lowered? Is there a way that a non-energised wire could be used, to gradually lower the pan until it's in its lowered position?

 

[AM9]

What keeps the pans lowered? Is there a way that a non-energised wire could be used, to gradually lower the pan until it's in its lowered position?

I doubt it as the contact area of most pantographs sit below the roofline when fully retracted to maintain the loading gauge.

 

[ainsworth74]

Or better still overhead rail!

What's the maximum speed you can use overhead rail?

 

[Metobusfan]

Well I arrived at City at about 6pm to find chaos. The station was closed, there were plenty of staff on duty who were advising people for Northbound services to go to St Pancras. I walked up to Farringdon to get the tube, and at Farringdon I spoke to another member of Thameslink staff to check trains were running from St Pancras. He said they were. Another passenger then interrupted and said he'd heard the trains were only running from Kentish Town. The staff member said this was incorrect and they were running from St Pancras.



On arrival at St Pancras the shutters were down and the station closed. Staff advising people to go to Kentish Town but warning trains would be very busy as there were only 4 services an hour, all stations to Bedford.



I decided to go via Kings Cross to Hatfield instead and have arrived home over two hours later than normal (although 15 minutes of the delay was because I called in at the chippy on the way home!).



At the same time as I was being told to go to St Pancras, the Twitter team were Tweeting that there were no services at St Pancras. Sadly my phone battery was flat so Twitter was no help today. So yet again staff on the ground have not been provided with the correct information leading to additional inconvenience and delays to customers. The operator of these trains may have changed, but they are still just as bad at dealing with problems.



Realistically, is this likely to be fixed in the morning or should I go straight to Hatfield?

Thing is we on the ground get told one thing then things change!

 

[AM9]

What's the maximum speed you can use overhead rail?

I would think that it would be the same as wire catenary of the same contact wire path and subject to linespeed limits. There may be speed limitations for pantographs working right at the lower range of heights, but that couldn't be any worse than wire knitting at the same height.

 

[SAPhil]

I have been using St Pancras a lot more of late, and even on a Sunday there can be loads of people about, so I have to wonder how the hell it's going to work when there's one platform for loads of different trains arriving one after another, but going to different places (so people will stand about blocking your access because they want the next train).

Farringdon in the rush hour worries me more - at least the platform at St Pancras is fairly wide.

 

[swt_passenger]

What's the maximum speed you can use overhead rail?

Far above the speeds in the Thameslink core. On the Furrer and Frey website somewhere (other manufacturers are available) they say theirs is good for up to 230 km/h...

 

[jon0844]

Farringdon in the rush hour worries me more - at least the platform at St Pancras is fairly wide.

Good point. I wonder if there will be crowd control measures to limit the number of people allowed to enter the platforms?

The problem then is that people miss their train due to crowds waiting for a totally different service.

I used to miss trains at Old Street because if the Northern line was packed, they stopped people entering. But my train wasn't affected, which was infuriating.

 

[ainsworth74]

Far above the speeds in the Thameslink core. On the Furrer and Frey website somewhere (other manufacturers are available) they say theirs is good for up to 230 km/h...

Impressive!

 

[Tetchytyke]

Does the Smithfield siding have less clearance than the Northern & City Line? That has a (non-energised) overhead wire in the southbound tunnel to stop damage if a driver forgets to drop the pan.

I think the platforms will be fine when things are running normally- it works well enough with the Munich S-Bahn- but it's going to be a disaster whenever something goes up the spout.

 

[ComUtoR]

There is but it can only be used to physically lock it ( during isolation's or dragging a failed unit). When in service they are not locked down, only lowered.

I thought that the pantograph requires air to raise it and IS locked down (to prevent it bouncing around...) when not in use not just when isolated. Stones Faveley pantographs also have springs that hold it down and only raises when that air pressure is greater than the spring pressure.

When the Driver hit the AC select and Pan Up/Reset makes the pantograph rise but shouldn't have the Driver then got an ADD as the pantograph wouldn't have found a wire ? iirc the roof in Smithfield is high enough to cause a pan over height and trip an ADD.

As always, without the exact details of the course of events its difficult to ascertain what precisely happened.

On a related tangent... Why does the dual voltage alarm sound when on AC and you add DC but not vice versa ?

 

[Tom B]

I don't know if this already exists, but would it not be feasible to have a "dummy" segment of OHLE at the end of a section of OHLE which, should a pantograph come into contact with it, will return a signal or indicator to danger?

 

[HarleyDavidson]

I thought that the pantograph requires air to raise it and IS locked down (to prevent it bouncing around...) when not in use not just when isolated. Stones Faveley pantographs also have springs that hold it down and only raises when that air pressure is greater than the spring pressure.

When the Driver hit the AC select and Pan Up/Reset makes the pantograph rise but shouldn't have the Driver then got an ADD as the pantograph wouldn't have found a wire ? iirc the roof in Smithfield is high enough to cause a pan over height and trip an ADD.

As always, without the exact details of the course of events its difficult to ascertain what precisely happened.

On a related tangent... Why does the dual voltage alarm sound when on AC and you add DC but not vice versa ?

Excuse my ignorance on this, but what is an ADD please? :?

 

[swt_passenger]

Excuse my ignorance on this, but what is an ADD please? :?

An Automatic [Pantograph] Dropping Device.

Thread about it here: http://www.railforums.co.uk/showthread.php?t=76336

Will drop the pan if the contact section is damaged or if it over-extends in height.

Edited to add - the last post on the linked page is the most detailed if you want to skip the introductory ramblings...

 

[dewsnapsliding]

I got caught in this on the delayed 17.23 departed 17.30 from East Croydon.

There were evidently problems but we moved steadily as far as Crystal Palace when we waited a while. The driver came on and said that he couldn't open the doors to allow anyone off as not all the cars were in the platform.
We proceeded eventually through Tulse Hill to Herne Hill where we waited an age. Again the driver announced that he couldn't let us off for the same reason, and after sitting there for a while, someone let themselves off so driver had to re-set the Passcom.
Driver then announces we are terminating at E&C so we crawl there, arriving around 18.45.
On pulling in to E&C the driver announces that as the platforms aren't long enough, all passengers in cars 9-12 will have to walk forward to 8 to egress the train.

Why could this not have occurred at either of the 2 previous stations where pax had alternative travel options into London? It seems to me that this ridiculous situation was simply done as a convenience to Operational requirements, and nothing to help the pax. Evidently SDO is available, but refusal of Thameslink to use it where it would have helped the passengers. It's this type of inconsistency that really p*sses passengers off as they see it as the train company applying rules simply when it suits them.

Any thoughts?

 

[otomous]

I got caught in this on the delayed 17.23 departed 17.30 from East Croydon.

There were evidently problems but we moved steadily as far as Crystal Palace when we waited a while. The driver came on and said that he couldn't open the doors to allow anyone off as not all the cars were in the platform.
We proceeded eventually through Tulse Hill to Herne Hill where we waited an age. Again the driver announced that he couldn't let us off for the same reason, and after sitting there for a while, someone let themselves off so driver had to re-set the Passcom.
Driver then announces we are terminating at E&C so we crawl there, arriving around 18.45.
On pulling in to E&C the driver announces that as the platforms aren't long enough, all passengers in cars 9-12 will have to walk forward to 8 to egress the train.

Why could this not have occurred at either of the 2 previous stations where pax had alternative travel options into London? It seems to me that this ridiculous situation was simply done as a convenience to Operational requirements, and nothing to help the pax. Evidently SDO is available, but refusal of Thameslink to use it where it would have helped the passengers. It's this type of inconsistency that really p*sses passengers off as they see it as the train company applying rules simply when it suits them.

Any thoughts?

Well one immediate thought is that Thameslink services are driver only and if there are no driver only facilities for 12 car trains at Tulse Hill or Herne Hill then the driver would not be able to despatch them from there. (I don't know if Thameslink 377s have in cab CCTV for despatch though). At Elephant the Selective Door Opening will still only open the doors on the front 8 coaches but there is no need to despatch the train if it is going out of service, just check that it's empty and lock it up. If the TOC has local instructions not to release doors on a 12 car at these stations, staff on the ground can't just decide to ignore them. It might be an inconsistency to a passenger but a very obvious rule to those who have to implement the rules and have a view of the bigger picture.

 

[Bald Rick]

When the Driver hit the AC select and Pan Up/Reset makes the pantograph rise but shouldn't have the Driver then got an ADD as the pantograph wouldn't have found a wire ? iirc the roof in Smithfield is high enough to cause a pan over height and trip an ADD.

Yes it probably would, if the pantograph was raised in Smithfields.
--- old post above --- --- new post below ---

On a related tangent... Why does the dual voltage alarm sound when on AC and you add DC but not vice versa ?

They used to, but were amended when the northbound changeover was switched to City TL - they are now cancellable. Otherwise 319drivers would have the alarm going off from the changeover at City until leaving Farringdon.

 

[HarleyDavidson]

An Automatic [Pantograph] Dropping Device.

Thread about it here: http://www.railforums.co.uk/showthread.php?t=76336

Will drop the pan if the contact section is damaged or if it over-extends in height.

Edited to add - the last post on the linked page is the most detailed if you want to skip the introductory ramblings...

Thanks for that.

 

[ComUtoR]

They used to, but were amended when the northbound changeover was switched to City TL - they are now cancellable. Otherwise 319drivers would have the alarm going off from the changeover at City until leaving Farringdon.

many thanks

 

[W230]

I got caught in this on the delayed 17.23 departed 17.30 from East Croydon.

There were evidently problems but we moved steadily as far as Crystal Palace when we waited a while. The driver came on and said that he couldn't open the doors to allow anyone off as not all the cars were in the platform.
We proceeded eventually through Tulse Hill to Herne Hill where we waited an age. Again the driver announced that he couldn't let us off for the same reason, and after sitting there for a while, someone let themselves off so driver had to re-set the Passcom.
Driver then announces we are terminating at E&C so we crawl there, arriving around 18.45.
On pulling in to E&C the driver announces that as the platforms aren't long enough, all passengers in cars 9-12 will have to walk forward to 8 to egress the train.

Why could this not have occurred at either of the 2 previous stations where pax had alternative travel options into London? It seems to me that this ridiculous situation was simply done as a convenience to Operational requirements, and nothing to help the pax. Evidently SDO is available, but refusal of Thameslink to use it where it would have helped the passengers. It's this type of inconsistency that really p*sses passengers off as they see it as the train company applying rules simply when it suits them.

Any thoughts?

Yes. I think the driver might have forgotten or not been aware he could have stopped. Assuming you were in a 12 car 377 then all the platform lengths are programmed into Mitrac (we were told all in the country don't know if it's true though) and it will only open the correct number of doors for the length of platform. I've had to stop a 12 car at Elephant in the peak due to disruption and Mitrac did it's job just right only opening the front 8 but maybe this driver wasn't aware for some reason.

This is just like it does at Balcombe with a 12 car on the Down...

Also even though we don't use SDO we can still select the number of doors to open via an emergency release. Not surprised someone got annoyed and egressed themselves...

 

[Class377/5]

Yes. I think the driver might have forgotten or not been aware he could have stopped. Assuming you were in a 12 car 377 then all the platform lengths are programmed into Mitrac (we were told all in the country don't know if it's true though) and it will only open the correct number of doors for the length of platform. I've had to stop a 12 car at Elephant in the peak due to disruption and Mitrac did it's job just right only opening the front 8 but maybe this driver wasn't aware for some reason.

This is just like it does at Balcombe with a 12 car on the Down...

Also even though we don't use SDO we can still select the number of doors to open via an emergency release. Not surprised someone got annoyed and egressed themselves...

The SDO is always in use not they other way around expect an emergency release. For example you could have a four car on the middle of a 12 car platform and SDO is still used. This is because the system authorises the use of the doors at every point.

There's also the point to consider that Elephant & Castle is manned pretty much most of the day with Thameslink staff. Neither can be said for Herne Hill or Tulse Hill. Note the latter would likely block the points so shouldn't be used to terminate without destroying other services. Herne Hill isn't much better with limited staffing. That's without the point that only Elephant & Castle reconnections to Thameslink.

Also the reason for the slow progress may be cause Tulse Hill is NR Sussex and Herne Hill is NR Kent. With multiple events occurring at the same time its possible they were simply dealing with trains on a trains by train basis while dealing with the controls as well. After all the incident occurred as the first PM 12 car was booked to be in South London metro any way.

And the driver will need permission to stop out of course (not an emergency situation for trains queuing) from the signallers/control who are busy dealing with incident and may not be directly reachable. Not to mention the driver isn't allowed to use his mobile so won't know anything that's going on where as his passengers are getting website info along with human replies on twitter so he may not be fully aware of what's occurring.

 

[dewsnapsliding]

The SDO is always in use not they other way around expect an emergency release. For example you could have a four car on the middle of a 12 car platform and SDO is still used. This is because the system authorises the use of the doors at every point.

There's also the point to consider that Elephant & Castle is manned pretty much most of the day with Thameslink staff. Neither can be said for Herne Hill or Tulse Hill. Note the latter would likely block the points so shouldn't be used to terminate without destroying other services. Herne Hill isn't much better with limited staffing. That's without the point that only Elephant & Castle reconnections to Thameslink.

Also the reason for the slow progress may be cause Tulse Hill is NR Sussex and Herne Hill is NR Kent. With multiple events occurring at the same time its possible they were simply dealing with trains on a trains by train basis while dealing with the controls as well. After all the incident occurred as the first PM 12 car was booked to be in South London metro any way.

And the driver will need permission to stop out of course (not an emergency situation for trains queuing) from the signallers/control who are busy dealing with incident and may not be directly reachable. Not to mention the driver isn't allowed to use his mobile so won't know anything that's going on where as his passengers are getting website info along with human replies on twitter so he may not be fully aware of what's occurring.

Seems to be some confusion, we didn't stop at Tulse Hill, but would I be correct in saying that Crystal Palace is fully staffed being an Overground Station?

 

[Class377/5]

Seems to be some confusion, we didn't stop at Tulse Hill, but would I be correct in saying that Crystal Palace is fully staffed being an Overground Station?

No confusion, I never said you would stop, only why you shouldn't stop.

Overground control is separate from Sussex so would only let passengers out in an emergency, which this situation wasn't.

 

[SpacePhoenix]

Is there anyway a pan being raised could be detected (external of the train)? If there was then the signal could be held a red until the driver lowers the pan.

 

[Class2ldn]

Not as far as I know, wouldn't matter anyway, if you raised the pan and there's no wires there it keeps rising and causes damage so lowering it wouldn't make much difference.