Weird electrification at St Pancras?!?

[BRX]

I suppose I'd thought that it would be ok being in a tunnel the whole way, so not accessible by the public at all.

 

[hacman]

A rigid conductor bar also has the benefit vs traditional OLE of being very durable, so in places where replacement of damaged OLE would be difficult or very disruptive, it has some substantial advantage.

 

[DelW]

They don't do third rail extensions anymore, even small ones - Merseyrail had to buy battery trains just for a one station extension because they couldn't do more third rail.

That's a very different location though.

I suppose I'd thought that it would be ok being in a tunnel the whole way, so not accessible by the public at all.

I think you were right, since the Northern Line extension to Battersea Power Station was permitted.

 

[edwin_m]

That's a very different location though.

I think you were right, since the Northern Line extension to Battersea Power Station was permitted.

I don't think the safety objections to extending the Thamelink third rail to St Pancras would have been insuperable. But it's not clear what benefit would be had for the cost of doing so. The current changeover arrangement has the benefit that if there's a problem, several following trains can stack up behind before they start blocking other routes.

 

[Bald Rick]

Ive explained before why the changeover is where it is.

But in summary - power supply, and the issue of dual voltage earthing to a rather larger and more complex area.

Even where it is now there are no end of problems. Any who has visited Blackfriars recently will see a selection of new insulated rail joints ready to be put in to replace those that are damaged by the return currents.

 

[duffield]

Does the conductor bar cause excess wear and stress on the pantographs, due to its inflexibility compared to normal OHLE? Or is it not significant?

 

[Bald Rick]

Does the conductor bar cause excess wear and stress on the pantographs, due to its inflexibility compared to normal OHLE? Or is it not significant?

It would do if the pantographs were in contact with the bar, but as explained above, they are not. They are in contact with the wire that is physically bonded to the bar.

 

[edwin_m]

If anything, more flexibility in the OLE would increase the wear on the pantograph, because every "hard spot" at a support would apply extra pressure onto the carbons.

 

[I'm here now]

It is an overhead conductor rail, for tight spaces where regular OHLE isn’t preferable. You can also see it on the Elizabeth Line.

And throughout Palma intermodal station

 

[Beebman]

I'm currently in Sydney where the new Metro uses an overhead conductor rail in the city centre tunnel sections.