If (as has been suggested in some quarters) the driver had forgotten to lower the pantograph at Farringdon (as I understand is normal practice)
then
a) wouldn't the pantograph have hit the roof of the Snow Hill Tunnel before it hit the roof at Blackfriars?
b) is there some warning system if a train with pantograph raised tries to enter Snow Hill tunnel?
c) would it have continued to draw dc traction current? - are the "raise / lower pantograph" and "switch between ac / dc traction current" separate actions on the driver's part? (I'm assuming the train can't decide for itself whether to draw ac or dc power - surely the train would get confused at Farringdon if that was the case)
Why would it be needed? At stations like farringdon and Drayton park you need to be able to draw from both shoes and pan to leave the station as when you put the pan up the shoes are still on the 3rd rail. An alarm goes off in the cab to warn you however.
Meanwhile London24 has gone with:
"The First Capital Connect service blocked the southbound lane after the driver raised the pantograph and hit the ceiling."
395s can also switch while on the move.
Just wondering and excuse my lack of knowledge but can a changeover be done while mobile or not as the case might be?
I'm referring to all AC/DC trains where ever in use and not just in UK.
Yes.Class 395s are the Javelins - right?
They also travel on the classic third-rail network.I didn't know these even had shoes - I thought HS1 is all OHLE?
Class 395s are the Javelins - right?
I didn't know these even had shoes - I thought HS1 is all OHLE?
My understanding is that the older designs (313, 319) cannot switch on the move, but later designs (350, 377, 378, 395) can, if the TOC rules allow.
They don't as they have no shoes. They used to run on the WLL for Southern.I know the answer to this will make me look stupid, but where do 350s run on DC?
I know the answer to this will make me look stupid, but where do 350s run on DC?
They don't as they have no shoes. They used to run on the WLL for Southern.
EDIT: Having just checked, it seems all peak services now stop at Ebbsfleet, but I'm sure some didn't in the past. There are a few ECS though that aren't timetabled to stop, so they would changeover on the move.
Actually, they ran the full length of the East Croydon - Milton Keynes Central route with five units, (350112, 350113, 350114, 350117, 350118), temporarily based at Selhurst depot.They did on the WLL when they were on loan to Southern (who had to loan dual voltage rolling stock to FCC for Thameslink for a short while.) P16/17 at Clapham Junction was as far south as they usually went.
There isn't, no. See above post for explanation why not but when leaving Drayton park or farringdon having put the pan up you run with both shoes and pan in contact with the electrics.
If (as has been suggested in some quarters) the driver had forgotten to lower the pantograph at Farringdon (as I understand is normal practice)
then
a) wouldn't the pantograph have hit the roof of the Snow Hill Tunnel before it hit the roof at Blackfriars?
b) is there some warning system if a train with pantograph raised tries to enter Snow Hill tunnel?
c) would it have continued to draw dc traction current? - are the "raise / lower pantograph" and "switch between ac / dc traction current" separate actions on the driver's part? (I'm assuming the train can't decide for itself whether to draw ac or dc power - surely the train would get confused at Farringdon if that was the case)
There used to be an issue when the 319's were new. You'd be running on DC and need to reset an overload. The overload reset button being also the pan up button (pan up / reset). due to a technical problem when you pressed pan up / reset on DC conditions, the pan went up
Quite a few pans were knocked off of units at that time
Wondering if this is a similar technical problem with this unit?
I'm not exactly certain how the buzzer system works, but traction power can only be taken from one or the other, but not both simultaneously. In the cab there is "AC System Select", "Pan up/Reset" and "Pan Down/DC System Select" buttons for the driver to use depending on the particular changeover needed.
I know the answer to this will make me look stupid, but where do 350s run on DC?
This kind of thing, for whatever cause, is going to happen eventually on this route and it's going to end up causing hours of disruption. Isn't there a way of detecting the pan is up and setting the signal to red? I seem to remember that the Underground has such things which prevent subsurface stock from being decapitated by going down the tube lines.
Clive's UndergrounD Line Guides said:Height detectors are mounted a short distance west of Barons Court on the eastbound track, and will prevent a subsurface stock train from being run into the Piccadilly platforms at the station or, more importantly, the tube section. These consist of U-shaped glass tubes silvered on the inside (previously they contained mercury) arranged so that an overheight train will smash them, breaking a circuit. Such tubes are also mounted between Hounslow Central and Hounslow West stations.
That'd be the surface stock detector mentioned at the end of this page http://www.davros.org/rail/culg/piccadilly.html
I'd imagine those more knowledgeable then me would have an explanation as to why this would be unsuitable for the pan-up situation that this thread refers to - for starters the pan isn't located at the front of the train but (depending on set formation) on the 2nd/3rd carriage.
There were indeed some that did not stop at Ebbsfleet.
As for the fast ecs runs, don't most of those originate from Ashford anyway?