Overground
 

"Willms" wrote in message

Am Wed, 16 Sep 2009 22:00:32 UTC, schrieb 1506
auf uk.railway :

This is something I have wondered for some time. The Overground name
is contrived. The East London Line is a former Underground line
anyway.

It is marketing, and probably a good move.

This could create a brand for urban and suburban railways similar to
"S-Bahn" in Germany and German speaking countries, distinct from
"U-Bahn" resp. "Underground".

Yes, I think the London 'Overground' needs a new brand that doesn't get
confused with other overground trains. The obvious one would be 'Metro'
but that risks confusion with the Metropolitan line.

Overground
 

"Sim" wrote in message
...
On 18 Sep, 10:47, MIG wrote:
On 18 Sep, 09:44, "John Salmon" wrote:

"Sim" wrote Now let's be nice to each other! I did not know the details
Charles

kindly provided, but it does make sense. Interestingly, not only does
fourth rail (however wired) exist as far north as Harrow, but the last
time I looked there was quite a lot left further on, although some of
it was lying rather dismally in the four foot rather than perched on
insulators. It was never formally removed, in other words, although
doubtless disconnected.

Previous discussions have suggested that it is still there because it
is still connected. I think the running rails must be wired to the
fourth rail and then the fourth rail wired to earth in the way that
the running rails are in other third rail systems. (Not technical,
but I assume that it saved connecting the running rails for one sort
of train and duplicating the connections for another sort of train.)

Question: was this the system at Euston and Broad Street etc, ie
positive to earth, rather than a bit positive to a bit negative?

Presumably for an LU train, the difference between the rails is all
that matters, whereas for a three-rail train it's the difference
between positive and earth that matters, so a NR train on conventional
LU track would only be at 420 V or something?

I really doubt that the old fourth rail is in circuit with anything.
Some is missing, and other sections are lying in the four foot. Not
much continuity there, I would have thought!



But lying on the ground and connected to ground!?

DW downunder

Overground
 

"MIG" wrote in message
...
On 18 Sep, 09:44, "John Salmon" wrote:
"Sim" wrote Now let's be nice to each other! I did not know the details
Charles

kindly provided, but it does make sense. Interestingly, not only does
fourth rail (however wired) exist as far north as Harrow, but the last
time I looked there was quite a lot left further on, although some of
it was lying rather dismally in the four foot rather than perched on
insulators. It was never formally removed, in other words, although
doubtless disconnected.

Previous discussions have suggested that it is still there because it
is still connected. I think the running rails must be wired to the
fourth rail and then the fourth rail wired to earth in the way that
the running rails are in other third rail systems. (Not technical,
but I assume that it saved connecting the running rails for one sort
of train and duplicating the connections for another sort of train.)

Question: was this the system at Euston and Broad Street etc, ie
positive to earth, rather than a bit positive to a bit negative?

Presumably for an LU train, the difference between the rails is all
that matters, whereas for a three-rail train it's the difference
between positive and earth that matters, so a NR train on conventional
LU track would only be at 420 V or something?

Or nothing - there should be "no circuit", but I suspect could cause some
problems for track circuits.

DW down under

Overground
 

"John Salmon" wrote in message
...

That seems like a reasonable summary. Now, can someone explain succinctly
why the smaller 'National Rail' stations between Queens Park and Harrow &
Wealdstone, used by LU and LO, which were previously Silverlink-branded,
are now signed as LU (rather than LO) stations?

Network Rail owned stations leased to Tfl, who decided LU rather than LO
would be the station operator, as the majority user based on service
frequency, I believe.

Paul

Overground
 

On Sep 18, 10:17*am, Sim wrote:
On 18 Sep, 09:52, "DW downunder" reply@newsgroup wrote:





"John Salmon" wrote in message

...

"Sim" wrote
Now let's be nice to each other! SNIP As it is, it's in London.
Hooray!

That seems like a reasonable summary. Now, can someone explain succinctly
why the smaller 'National Rail' stations between Queens Park and Harrow &
Wealdstone, used by LU and LO, which were previously Silverlink-branded,
are now signed as LU (rather than LO) stations?

The name Bakerloo might have something to do with it. AIUI, the TfL strategy
is to make the Bakerloo the primary service provider for this section, if
not the whole way to Watford Jn. This may be linked in some way with the
Metropolitan Line Watford branch extension to Watford Jn.

DW downunder

The decision was made to transfer these stations to Underground
management at the time Overground was being defined. The Bakerloo is
probably seen as the senior partner as far as Harrow now, and further
changes (already discussed) seem likely to make that even more so in
the future.

In the old days, Queen's Park was the last LT-managed station on the
route to Watford, which was firmly BR (and before that LMS) thereafter
all the way to Watford. The Bakerloo was the "guest".

From 1964 a decline set in as far as LT was concerned, until by the
1970s there was no Bakerloo north of Queen's Park except a handful in
the peaks. Then Stonebridge Park depot was built as part of the
splitting of the Bakerloo around the time the first part of the
Jubilee line opened (1979) and tube trains started running north of
Queen's Park more frequently again.

One thought: will Headstone Lane--Watford High Street inclusive also
be transferred to Underground management eventually, particularly
after Met trains start serving Watford HS on their way from Croxley to
Watford Junction?

Why not go the whole hog and include a new LU ticket office in the
rebuilt Watford Junction station?
Plans already show a possible new direct access from buses/street to
platforms 1-4!

JohnG

Overground
 

"Recliner" wrote in message
...
"Willms" wrote in message

Am Wed, 16 Sep 2009 22:00:32 UTC, schrieb 1506
auf uk.railway :

This is something I have wondered for some time. The Overground name
is contrived. The East London Line is a former Underground line
anyway.

It is marketing, and probably a good move.

This could create a brand for urban and suburban railways similar to
"S-Bahn" in Germany and German speaking countries, distinct from
"U-Bahn" resp. "Underground".

Yes, I think the London 'Overground' needs a new brand that doesn't get
confused with other overground trains. The obvious one would be 'Metro'
but that risks confusion with the Metropolitan line.

Wasn't that the purpose of "London Rail"?

DW downunder

Overground
 

On 18 Sep, 11:34, "DW downunder" reply@newsgroup wrote:
"MIG" wrote in message

...





On 18 Sep, 09:44, "John Salmon" wrote:
"Sim" wrote Now let's be nice to each other! I did not know the details
Charles

kindly provided, but it does make sense. Interestingly, not only does
fourth rail (however wired) exist as far north as Harrow, but the last
time I looked there was quite a lot left further on, although some of
it was lying rather dismally in the four foot rather than perched on
insulators. It was never formally removed, in other words, although
doubtless disconnected.

Previous discussions have suggested that it is still there because it
is still connected. *I think the running rails must be wired to the
fourth rail and then the fourth rail wired to earth in the way that
the running rails are in other third rail systems. *(Not technical,
but I assume that it saved connecting the running rails for one sort
of train and duplicating the connections for another sort of train.)

Question: was this the system at Euston and Broad Street etc, ie
positive to earth, rather than a bit positive to a bit negative?

Presumably for an LU train, the difference between the rails is all
that matters, whereas for a three-rail train it's the difference
between positive and earth that matters, so a NR train on conventional
LU track would only be at 420 V or something?

Or nothing - there should be "no circuit", but I suspect could cause some
problems for track circuits.


Oops, I think I meant positive and neutral.

Overground
 

On 18 Sep, 09:52, "DW downunder" reply@newsgroup wrote:
"John Salmon" wrote in message

...

"Sim" wrote
Now let's be nice to each other! SNIP As it is, it's in London.
Hooray!

That seems like a reasonable summary. Now, can someone explain succinctly
why the smaller 'National Rail' stations between Queens Park and Harrow &
Wealdstone, used by LU and LO, which were previously Silverlink-branded,
are now signed as LU (rather than LO) stations?

The name Bakerloo might have something to do with it. AIUI, the TfL strategy
is to make the Bakerloo the primary service provider for this section, if
not the whole way to Watford Jn. This may be linked in some way with the
Metropolitan Line Watford branch extension to Watford Jn.

The Bakerloo are the primary provider for this section and have been
for a while. A 7 car train every 10 mins (more in the peak and south
of Stonebridge Park) compared to a 3 car train every 20 mins for LO.
It was only when TfL took over responsibility for the stations that
they became Bakerloo line managed though and much of the kit is still
National Rail (like the ticket machines).

Overground
 

On 18 Sep, 11:10, Sim wrote:
On 18 Sep, 10:47, MIG wrote:





On 18 Sep, 09:44, "John Salmon" wrote:

"Sim" wrote Now let's be nice to each other! I did not know the details Charles

kindly provided, but it does make sense. Interestingly, not only does
fourth rail (however wired) exist as far north as Harrow, but the last
time I looked there was quite a lot left further on, although some of
it was lying rather dismally in the four foot rather than perched on
insulators. It was never formally removed, in other words, although
doubtless disconnected.

Previous discussions have suggested that it is still there because it
is still connected. *I think the running rails must be wired to the
fourth rail and then the fourth rail wired to earth in the way that
the running rails are in other third rail systems. *(Not technical,
but I assume that it saved connecting the running rails for one sort
of train and duplicating the connections for another sort of train.)

Question: was this the system at Euston and Broad Street etc, ie
positive to earth, rather than a bit positive to a bit negative?

Presumably for an LU train, the difference between the rails is all
that matters, whereas for a three-rail train it's the difference
between positive and earth that matters, so a NR train on conventional
LU track would only be at 420 V or something?

I really doubt that the old fourth rail is in circuit with anything.
Some is missing, and other sections are lying in the four foot. Not
much continuity there, I would have thought!

It is still wired to the running rails, if you look from a train at
the other track, you can see the connections. The running rails were
never the continuous electrical return and were not bonded together.
The fact that the rail lies in the four foot doesn't matter as it is
earthed, missing sections will have been bypassed with cabling and
very little is actually missing if you look for it. If nothing else,
it has to be connected to something, due to possible induction from
the 25kV AC running along side.

Overground
 

On 18 Sep, 08:14, Sim wrote:
On 18 Sep, 07:17, "
wrote:





Charles Ellson wrote:
On Thu, 17 Sep 2009 22:34:15 +0100, Charles Ellson
wrote:

On Thu, 17 Sep 2009 13:21:29 -0700 (PDT), "
wrote:

MIG wrote:
On 17 Sep, 10:15, "Peter Masson" wrote:
"Sim" wrote

Some differences between Overground and Underground:
1. Third rail electrification rather than fourth, so not compatible
for through running.

The NLL is 25 kV OHLE between Acton and Camden Road, and between Dalston
Kingsland and Stratford, and will be all the way between Acton and Stratford
once the NLL refurbishment is complete. The WLL switches from 25 kV OHLE to
3rd rail between North Pole Junction and Shepherds Bush. Goblin remains
diesel worked (and if it is electrified it will be 25 kV OHLE.

BTW, the Broad Street to Dalston line, most of which is being incorporated
into the ELL, was originally 4th rail, but IIRC was converted to 3rd rail
before closure.

Peter

And all electrified parts of the current London Overground were four
rail at some point, weren't they? *Ah, maybe not Dalston to Stratford.

I believe the stretch from Queens Park to Harrow & Wealdstone is still
four rail, otherwise Bakerloo passengers would have to get out and
push!

It is 3rd rail with the 4th rail bonded to the running rail which
carries the traction return current. The LU 4-rail system does not
have a deliberate electrical connection between the 3rd/4th rails and
the running rails and is only loosely connected to earth/0v to enable
control equipment to detect earthing of either electric rail. A
further consequence of this arrangement is that trains running over
such sections require higher-rated insulation than is necessarily on
LU (660v to earth rather than 420v to earth) although IMU all current
LU stock
... has been so equipped since the 1960s.

I'm afraid all that technical theory stuff just goes over my head.
I'm a straightforward, practical sort of person, and as far as I'm
concerned, if you count the rails and there are four of them, then
there are four rails. *That's just common sense, and no amount of
fancy electrical theory is going to change that.- Hide quoted text -

- Show quoted text -

Now let's be nice to each other! I did not know the details Charles
kindly provided, but it does make sense. Interestingly, not only does
fourth rail (however wired) exist as far north as Harrow, but the last
time I looked there was quite a lot left further on, although some of
it was lying rather dismally in the four foot rather than perched on
insulators. It was never formally removed, in other words, although
doubtless disconnected.


And another poster has also rightly pointed out the existence of 25kV
in various places, which is why dual-voltage roilling stock is needed.
To add a little savour, parts of the 25kV NLL route (Camden Road
area?) have third rail as well as OHLE -- a rare combination, I would
suggest.


Although the amount of mixed track will be reduced once the current
works have finished, as the 3rd rail will be removed from the NLL
tracks through Camden and the 3rd rail will only reach Highbury &
Islington on the southern pair of tracks from the East London line.
There will be a short dual system connection between them.

If I came across such a compromise system in a foreign capital, I
would be intrigued.


There are some dual system units in use in Hamburg.

As it is, it's in London. Hooray!