Thameslink Core pantograph strike

[Bikeman78]

No magnet, it was just the traction system detecting both voltages - it only buzzed when the pan was up.




IIRC it couldnt be cancelled.

My limited recollection is that the buzzer sounded constantly on northbound trains from the moment that the pantograph was raised until the last shoe ran off the third rail.

 

[Deepgreen]

700s don't have the ability to retract the shoes. Only 717s can do this.

Thanks.

It's already acceptable. The risk is minimal and incidents are rare.

Have there not already been three incidents this year? Perhaps whoever stated that was wrong (or I misread it).

 

[jdp30]

Have there not already been three incidents this year? Perhaps whoever stated that was wrong (or I misread it).

I don't think they are all this year - The last I can remember is around April 2022.

 

[ComUtoR]

Have there not already been three incidents this year?

I couldn't tell you how many incidents have happened but relative to the number of trains that successfully drop the pan. It's tiny.

I have never heard of a member of public getting injured or seen millions of pounds of damage quoted. Unless that was the case, nothing much will be done. You could employ a single member of staff to stand there 24/7 telling each Driver to drop the pan and I could almost guarantee someone will still forget.

 

[Busaholic]

How rarely is "it happens rarely" given that we seem to have something like this reported every few months?

I seem to remember reading on this forum from a contributor who knew his stuff that in the early years of operation there were on average three to four occasions per annum, which doesn't strike me as rare.

 

[Bald Rick]

As has been said elsewhere, a pantograph going overheight should drop automatically. Why did this not happebn here? Is the distance between the end of the wires and the next overheight structure (the office building) too short for that process to operate?

Good question. I thought that the design was such that a train departing City TL southbound with the pan up would indeed see the pan go overheight, ADD, and then drop back before the puddle dock offices. I assume that was from a start at City TL, and not on the move.

Thanks.


Have there not already been three incidents this year? Perhaps whoever stated that was wrong (or I misread it).

I stated above somewhere that my recollection is of 3/4 incidents since the 700s started operating, which was 2016.

 

[Peter Mugridge]

I don't think they are all this year - The last I can remember is around April 2022.

I was caught up in one earlier this year.

Ended up having to hot foot it from Farringdon to London Bridge...

A few months earlier I had to bail out at City Thameslink for Farringdon on foot because of another such instance.

 

[class717]

Presume he wasnt in ATO?

Nope driving manual at the time

 

[Bald Rick]

I was caught up in one earlier this year.

Ended up having to hot foot it from Farringdon to London Bridge...

A few months earlier I had to bail out at City Thameslink for Farringdon on foot because of another such instance.

Are you sure that was Pan up in deoarture southbound, and not simply a train failing to change voltages?

 

[ComUtoR]

Good question. I thought that the design was such that a train departing City TL southbound with the pan up would indeed see the pan go overheight, ADD, and then drop back before the puddle dock offices. I assume that was from a start at City TL, and not on the move.

Was that before or after the introduction of the 700s ? 319s would struggle in full power and the linespeed was only 15mph back then. With a change to more powerful units that can storm up the gradient maybe the timing is a little shorter than expected. Previous strikes have seen the pan hit the building but this looks like it caught under just at the wrong time, and yes, with a run up..

 

[Nicholas Lewis]

I couldn't tell you how many incidents have happened but relative to the number of trains that successfully drop the pan. It's tiny.

It is but the consequences are catastrophic. Yesterday no trains for hours and a huge amount of cancelled services for the remainder of the day. This is a mission critical route to so many other services and with minimal fallback arrangements it needs to achieve 100% against issues within the industries control.

 

[Mr. SW]

Is there a way of dropping the pan manually, say by opening a little locked panel in the appropriate car and pumping a handle or pushing a lever? I'm sure there's something on locos, but is there anything on EMUs?

 

[Class 170101]

To me it seems a risk has not been mitigated, that of a passenger or ECS being required to run non-stop through either or both Farringdon or City Thameslink stations as it seems from what I have read that these trains are required to stop to activate the raise or lower pan sequence. This seems to be an oversight and that they should be able to run through and raise or lower the pantograph without huamn intervention.

 

[Nicholas Lewis]

To me it seems a risk has not been mitigated, that of a passenger or ECS being required to run non-stop through either or both Farringdon or City Thameslink stations as it seems from what I have read that these trains are required to stop to activate the raise or lower pan sequence. This seems to be an oversight and that they should be able to run through and raise or lower the pantograph without huamn intervention.

Given Northbound trains stop at City Thameslink on a Sunday to c/o but dont open doors it should be mandated that same process should apply to ECS movements

 

[Class 170101]

Given Northbound trains stop at City Thameslink on a Sunday to c/o but dont open doors it should be mandated that same process should apply to ECS movements

I'd say both Farringdon and City Thameslink to give two chances for the changeover to take place.

 

[ComUtoR]

It is but the consequences are catastrophic. Yesterday no trains for hours and a huge amount of cancelled services for the remainder of the day. This is a mission critical route to so many other services and with minimal fallback arrangements it needs to achieve 100% against issues within the industries control.

I do agree but 'catastrophic' is overstating a fair bit. Other incidents can be just as 'catastrophic' and its always been know that The Core spends most of its time on a knife edge. How much should the industry spend on those few incidents ?

Given Northbound trains stop at City Thameslink on a Sunday to c/o but dont open doors it should be mandated that same process should apply to ECS movements

I'm pretty sure that stopping to change over on ECS is mandatory Southbound too. The Driver appears to have forgotten to stop.

 

[Bald Rick]

Was that before or after the introduction of the 700s ?

Before, but with the 700s taken into account.

 

[Nicholas Lewis]

I do agree but 'catastrophic' is overstating a fair bit. Other incidents can be just as 'catastrophic' and its always been know that The Core spends most of its time on a knife edge. How much should the industry spend on those few incidents ?

The core needs to be bullet proof against own goals the industry has enough to contend with which it has no control over

 

[Samzino]

The core needs to be bullet proof against own goals the industry has enough to contend with which it has no control over

This

It can't cost that much time for a laser based beam system that checks if the pantos are still up (due to them breaking the beam) and if so just holds the signal at Danger. That way its redundant against mechanical failures, auto system failures and human failure to drop the pan manually. A few seconds or minute more here and there can't be worse than part closure of the core for x amount of hours if a breach happens as we've seen with these cases.

 

[800301]

Is there a way of dropping the pan manually, say by opening a little locked panel in the appropriate car and pumping a handle or pushing a lever? I'm sure there's something on locos, but is there anything on EMUs?

I’ve not seen a modern EMU that doesn’t have a Pan down button easily accessible in the cab, if low speed coasting is in operation you need to be able to drop the pan to run under the section and then pan back up after at a speed of no more than 20mph

 

[DerekC]

The system for pan control for Class 700s is designed the way it is because Network Rail made it an absolute requirement that voltage change in the Thameslink core had to be done whilst stationary - so there is no way that an ECS train should ever run through without stopping. The train is, from what I remember, perfectly capable of voltage change on the move, and it uses ETCS balises to determine position so could initiate the pan drop just as the Class 800 does. It's just that the "on the move" case wasn't allowed, so wasn't designed for. I think NR preferred the odd pantograph being wiped off to the perceived risk to the infrastructure of changeovers on the move.

 

[Peter Mugridge]

Are you sure that was Pan up in departure southbound, and not simply a train failing to change voltages?

The barrier staff specifically stated it was a pantograph incident when I asked what had happened.

...and no, I can't remember what date it was.

 

[whoosh]

The system for pan control for Class 700s is designed the way it is because Network Rail made it an absolute requirement that voltage change in the Thameslink core had to be done whilst stationary - so there is no way that an ECS train should ever run through without stopping. The train is, from what I remember, perfectly capable of voltage change on the move, and it uses ETCS balises to determine position so could initiate the pan drop just as the Class 800 does. It's just that the "on the move" case wasn't allowed, so wasn't designed for. I think NR preferred the odd pantograph being wiped off to the perceived risk to the infrastructure of changeovers on the move.

I suppose Network Rail wasn't planning for trains to still be driven manually on the route in 2023 using the conventional lineside signals...

 

[Bald Rick]

The barrier staff specifically stated it was a pantograph incident when I asked what had happened.

...and no, I can't remember what date it was.

A pantograph incident doesnt mean that one has been left up and had an unscheduled meeting at Puddle Dock.

 

[Robcuk]

When heading into Smithfield's the signaller calls you prior and checks that your pan isn't up perhaps units with a 5 head code heading south should be contacted to check it's down - bring them to a red at farringdon and make the call.

I remember one driver heading north in a wrong direction move and not stopping to put the pan up luckily the consequences are limited to just running out of power

 

[uglymonkey]

I do take the point though if something happens "in the core", it screws over train services all over from Brighton, Cambridge, Luton and Peterborough. Are the lines in the core bi-directional? So that you could work round a stranded train and run a very limited service on the other line? Or is this not allowed for safety?

 

[Robcuk]

I do take the point though if something happens "in the core", it screws over train services all over from Brighton, Cambridge, Luton and Peterborough. Are the lines in the core bi-directional? So that you could work round a stranded train and run a very limited service on the other line? Or is this not allowed for safety?

I think fitters were working on the stranded unit to remove the pan hence no running on the other line

 

[ThameslinkUser]

Are the lines in the core bi-directional? So that you could work round a stranded train and run a very limited service on the other line? Or is this not allowed for safety?

This procedure was in place utilising the points south of City Thameslink on the day in question. Didn't help the performance of all regions served though.

 

[jon0844]

I do take the point though if something happens "in the core", it screws over train services all over from Brighton, Cambridge, Luton and Peterborough. Are the lines in the core bi-directional? So that you could work round a stranded train and run a very limited service on the other line? Or is this not allowed for safety?

Yes, but as you can imagine the capacity is drastically reduced and so a plan kicks in to cancel many services to thin things out, and route some into King's Cross from places like Peterborough (which then has capacity issues) if possible.

If you're in the core and only wishing to get from one end to the other, say St Pancras to London Bridge, then perhaps the impact isn't so bad as you can take almost every train that comes regardless of where it came from, is going, or how late it is. For longer trips, it's going to be a mess.

 

[jdp30]

Are the lines in the core bi-directional?

In theory yes, in practice I think they're very hesitant to do it and as above says it absolutely kills the service on the branches.