Overhead wires

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pt_mad

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I was just wondering why the ECML, Fen Line and other lines were constructed with the suspension cable method of holding up the wires rather than full overhead masts like the WCML.

Has the suspension cable method ceased now in terms of new construction?
 
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MidnightFlyer

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I believe it was to save money, recommended by civil servants, as opposed to those in the rail industry who wanted 'proper' OHLE, like that on the WCML.
 

pt_mad

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I believe it was to save money, recommended by civil servants, as opposed to those in the rail industry who wanted 'proper' OHLE, like that on the WCML.
Is it likely Great Western will have the full works?

Also why do some sections of just double track have the twin mast system and then other parts of the same lines have full overhead masts just for twin tracks?
 

pt_mad

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Probably, being as full masts are currently being installed on the Chat Moss line (and electrification is a rolling programme, using the same equipment for different projects).
I see. I think the suspension wires look better for some reason.

I like your eagle ID picture by the way. How did you fit a laptop in the nest?:)
 

pt_mad

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Will they ever start to replace them with proper masts or just keep maintaining them? I am guessing the cables have to be replaced sometimes?
 

PaxVobiscum

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So how does it work out in practice for reliability? For example, are there more OHLE problems per thousand (or 10K or whatever) train miles on the ECML than on the WCML?

Innocent question, no axe to grind. I tend to travel more on the ECML because of lower Advance fares.
 

LE Greys

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Will they ever start to replace them with proper masts or just keep maintaining them? I am guessing the cables have to be replaced sometimes?
They've gone through at least one replacement cycle near my area, so I imagine that they're never going to be reinforced. After all, that would involve overnight posessions and diesel haulage because of a lack of power. Still, if they ever decided to upgrade to 140 mph (and Hell freezes over) . . .
 

ainsworth74

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So how does it work out in practice for reliability? For example, are there more OHLE problems per thousand (or 10K or whatever) train miles on the ECML than on the WCML?
I would say there are more overhead line problems in the areas of the ECML that use headspans (which is what the type with two masts and the wires strung up between them is called) than areas which use more standard cantilevered supports. So whilst there probably are more problems on the ECML it's a restricted part of the route rather than the whole thing.
 

LE Greys

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I would say there are more overhead line problems in the areas of the ECML that use headspans (which is what the type with two masts and the wires strung up between them is called) than areas which use more standard cantilevered supports. So whilst there probably are more problems on the ECML it's a restricted part of the route rather than the whole thing.
Huntingdon is a major problem. The headspans there are especially wide and the line is on a curve. Not sure if those would be contributory factors, but I imagine so.
 

Mike C

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Huntingdon is a major problem. The headspans there are especially wide and the line is on a curve. Not sure if those would be contributory factors, but I imagine so.
Agreed - and I have made this point in years gone by. The headspans there cover all 4 lines of the ECML, the two main platforms, bay platform 1, the track AND the station building, and as you say, it's on a curve - albeit a 125mph one. At the north end of the station the OLE is squeezed under the Brampton Road overbridge which is very low.

In this image - you can't even see the masts as they're out of shot to the left and right:

http://en.wikipedia.org/wiki/File:Huntingdon_train_station.JPG

The headspans here were pulled down in 2 infamous incidents that made the national news because of severe disruption. One on the hottest day of 2006 when passengers on a train stranded in the fens due to the Huntingdon incident broke windows and wandered on the track. The second was in December 2010 when, again, the headspans were snagged, and it closed the ECML (all 4 lines - the main weakness of headspan catenary) about 3 days before Christmas.

http://www.bbc.co.uk/news/uk-england-12049884

Whether these incidents would have happened with portal structures is of course unknown.
 

yorksrob

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Since Network Rail seem to be toying with the idea of converting the whole of the Southern Region to overhead, I wonder whether re-enforcing the problem areas on the ECML might be a more cost effective way of improving overall reliability.
 

CosherB

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I worked at BR during ECML electrification and I believe that the decisions made on cutting corners was entirely down to BR
Indeed, but that was no doubt because the civil servants had BR's goolies in the vice and would not come up with the right amount of money to do the job, so BR had to compromise and cut corners. It was ever thus and that situation is THE biggest reason why a nationalised railway in UK can never work properly.

Privatisation is far from perfect, but at least it produces the money to do stuff properly (hence masts on the newly-approved electrifications). The reason is that business sense prevails; it makes no sense to save a bit of money in the initial construction and end up with an inferior system that costs more than those savings over the years as trains bring the wires down. And then at some stage you're probably going to have to replace the headspans with masts anyway to make the service reliable enough.

'Buy it cheap, buy it twice' as a wise man once said.
 

yorksrob

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Alas, since there have been so few electrification schemes during the intervening fifteen years of privatisation, it's difficult to make a meaningful comparison.
 

ainsworth74

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Imagine if we'd committed to wiring one major mainline (and infill around it) per decade. WCML in the 60s, ECML in the 70s (wasn't this actually the plan at one point to wire up the ECML almost as soon as the WCML was finished?), perhaps MML in the 80s and GWML in the 90s. One long forty plus year rolling electrification programme, that would have been quite something.

HS1

Paddington to Heathrow

Edinburgh to Airdrie

Bits of the NLL and WLL (switched from 3RE to OHLE)

Any more?
Not exactly on the scale of wiring undertaken by BR or being undertaken right now though is it?
 

yorksrob

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HS1

Paddington to Heathrow

Edinburgh to Airdrie

Bits of the NLL and WLL (switched from 3RE to OHLE)

Any more?
A short section between stoke and Crewe I believe.

I don't really count conversion from one form of electrification to another, however, the other schemes add up to very little in comparison to what was achieved during the 1980's.
 

pt_mad

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I noticed there are odd sections of the ECML where there are two single masts on each side with the triangles on.

Hard to explain what I mean but take a look at this picture from Tamworth on the WCML. Its an old pic but shows the mast setup I mean.

http://www.trainspots.co.uk/100-199/tamworth/tamworth_4.jpg

Couldn't the ECML have applied this principle? That way only two supports required and no top bar.
 

LE Greys

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I noticed there are odd sections of the ECML where there are two single masts on each side with the triangles on.

Hard to explain what I mean but take a look at this picture from Tamworth on the WCML. Its an old pic but shows the mast setup I mean.

http://www.trainspots.co.uk/100-199/tamworth/tamworth_4.jpg

Couldn't the ECML have applied this principle? That way only two supports required and no top bar.
They are in certain places around Welwyn and New Southgate. I've often wondered why that is not used more, but it might have something to do with the masts being inside the 'ten-foot' and not outside.
 

Mike C

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It requires a spacing between the lines running in the same direction that may not exist. If you take the southern section of the ECML, for example, where you have (running from East to West) Up slow, Up fast, Down fast, Down slow - there is insufficient space between the up slow and up fast or down slow and down fast to have an OLE mast and not have it fouling the loading gauge.

To employ the set up shown in that photo, they would have to realign many miles of track which would have been far more expensive than using headspan and isn't possible in many areas (over bridges for example).
 

Bald Rick

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I worked at BR during ECML electrification and I believe that the decisions made on cutting corners was entirely down to BR
Probably because BR engineers saw that head spans work perfectly well on multi-track lines throughout Europe (which they still do to this day) and that saving cash was the best way to get the project authorised. Back in those days any project worth more than £2m had to go to the Department for authority.
 

pt_mad

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It requires a spacing between the lines running in the same direction that may not exist. If you take the southern section of the ECML, for example, where you have (running from East to West) Up slow, Up fast, Down fast, Down slow - there is insufficient space between the up slow and up fast or down slow and down fast to have an OLE mast and not have it fouling the loading gauge.

To employ the set up shown in that photo, they would have to realign many miles of track which would have been far more expensive than using headspan and isn't possible in many areas (over bridges for example).
That explains that then.

They have actually since removed that mast setup from Tamworth. When the four tracking was completed between there and Rugely they put a couple of regular solid masts up spanning the width of all four tracks.

Not sure why.
 

LE Greys

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Imagine if we'd committed to wiring one major mainline (and infill around it) per decade. WCML in the 60s, ECML in the 70s (wasn't this actually the plan at one point to wire up the ECML almost as soon as the WCML was finished?), perhaps MML in the 80s and GWML in the 90s. One long forty plus year rolling electrification programme, that would have been quite something.
I believe it was, but BR decided to go down a different route. The main reasons for this were the Deltics, APT and HST. At first, they thought that the ECML was doing fine with Deltics. Then, the APT was just around the corner and they wanted to hang on until it was ready (AIUI, there was a gas turbine/diesel version on the drawing board for the second batch). After that, the HST seemed adequate until they finally got round to full electrification.

The first part was also the era of cheap oil, so electrification seemed a bit pointless, and only got back on the agenda after the 1973 oil crisis.
 

DaveNewcastle

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I was just wondering why the ECML, Fen Line and other lines were constructed with the suspension cable method of holding up the wires rather than full overhead masts like the WCML.
To help you with the terminology of OHLE components and to give you some of the debate, analysis and commetary on the ECML structures, there's a few other threads already in this section - I'd be surprised if these didn't help you.

25KV OLE diagrams & support info ?

East Coast Overhead line

Limitations of British OLE

and perhaps also:
Our two electrification systems
 

Bald Rick

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Imagine if we'd committed to wiring one major mainline (and infill around it) per decade. WCML in the 60s, ECML in the 70s (wasn't this actually the plan at one point to wire up the ECML almost as soon as the WCML was finished?), perhaps MML in the 80s and GWML in the 90s. One long forty plus year rolling electrification programme, that would have been quite something.



Not exactly on the scale of wiring undertaken by BR or being undertaken right now though is it?
The MML was always first in the queue after the WCML, and was to have the rolling stock displaced by the APTs. Electrification to Bedford was phase 1.

The ECML jumped the queue when it was realised the case was better, i.e higher return on investment. However the original ECML electrification as proposed to Govt in the early 80s was planned only to Leeds and Newcastle, with Class 89s hauling MkIII coaches. Subsequent submissions saw the extension to Edinburgh and the IC225 fleet we have today.
 

HSTEd

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I thought the ECML only got built because it just so happened that high BCR electrification projects overordered Mark III equipment which slashed the cost of going north from Peterborough.

Headspans seem to work fine in the other places they are used.

Would you rather that BR had insisted on overengineered "portals" and thus had achieved no electrification north of London outside the WCML?
They produced a significant electrification programme at suprisingly low cost, it is rather impressive, especially considering the ECML wire is not really unreliable even though it is not perfect.
 
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