St Pancras International
 

"Roland Perry" wrote in message
...
In message , at 11:12:46 on Mon,
30 Jul 2007, BH Williams remarked:
Access to the northern end of HS1 is fairly limited, that to and from the
WCML being by the NLL, which presents pathing problems, from the MML being
by a single route from the Down Slow, and that from the ECML also being
single track.

Isn't the line to/from the NLL also a single track to/from the
westbound[1] NLL, so an eastbound movement would cause even more problems.

[1] shared most of the way with the route from NLL to ECML
--
Roland Perry
Yes.
Brian

St Pancras International
 

In message , at 11:26:21 on
Mon, 30 Jul 2007, Paul Scott remarked:
Which reminds me, in the more general sense, what plans might there be for
MML capacity improvement in the medium term.

The best chance for capacity improvement in the medium term (which I
would say was 5-10 years) would be extending the electrification of FCC
in stages, eventually all the way to Leicester, and run maybe an
additional 2tph of the formerly Bedford-terminating trains through the
Thameslink2015 tunnels. And this might require a slight re-balancing of
Leicester/Bedford versus Cambridge/KingsLynn and Peterborough trains
according to the demand on those lines.
--
Roland Perry

St Pancras International
 

"BH Williams" wrote in message
...
Yes, it does. Currently, both TVM signalling and OCS start just east of
Fawkham Junction, somewhat to the north of Ashford.


Do you mean to say that the entire line from St. Pancras will run this type
of signalling and power source? What will happen to the contact shoes,
interestingly enough?

Also, what is TVM and OCS?

St Pancras International
 

In article ,
writes

"BH Williams" wrote in message
...
Yes, it does. Currently, both TVM signalling and OCS start just east of
Fawkham Junction, somewhat to the north of Ashford.


Do you mean to say that the entire line from St. Pancras will run this type
of signalling and power source? What will happen to the contact shoes,
interestingly enough?

Also, what is TVM and OCS?


OCS - Overhead Contact System - 25kV wires in the air. Three feeder
stations between London and Folkestone - the same as UK main lines
except that it can supply a higher current.

TVM - can't remember the French - basically a transmission system using
the rails and track circuits to send a speed code to the train. Train
picks it up and displays maximum speed, slow down, etc. to driver and
also controls the ATP (Automatic Train Protection) system.

OCS goes all the way to St Pancras International buffer stops, but the
last section has a lower current capacity (about 2km from tunnel portal
is the neutral section IIRC).

TVM stops at the tunnel portal and lineside signals are provided from
there backed by KVB (a balise based ATP system).

--
John Alexander,

Remove NOSPAM if replying by e-mail

St Pancras International
 

On Jul 30, 9:15 pm, John wrote:

TVM stops at the tunnel portal and lineside signals are provided from
there backed by KVB (a balise based ATP system).

Will E* remove AWS equipment as well as third rail contact gear at
some point?

It's interesting that the trains will continue to require separate
British, French and Belgian safety systems solely to approach the
respective termini (and French classic lines for certain sets of
course). Plenty of complexity there to add to running costs - I
wonder how quickly E* will remove the shoe gear...

St Pancras International
 

"John" wrote in message
...
In article ,
writes

"BH Williams" wrote in message
...
Yes, it does. Currently, both TVM signalling and OCS start just east of
Fawkham Junction, somewhat to the north of Ashford.


Do you mean to say that the entire line from St. Pancras will run this
type
of signalling and power source? What will happen to the contact shoes,
interestingly enough?
They'll be removed, there being no further use for them

Also, what is TVM and OCS?


OCS - Overhead Contact System - 25kV wires in the air. Three feeder
stations between London and Folkestone - the same as UK main lines
except that it can supply a higher current.
I thought it was 'Overhead Catenary System', but I could be wrong-
affectionately (at least until it comes down) referred to as 'the knitting'

TVM - can't remember the French - basically a transmission system using
the rails and track circuits to send a speed code to the train. Train
picks it up and displays maximum speed, slow down, etc. to driver and
also controls the ATP (Automatic Train Protection) system.
Transmission Voie Machine

OCS goes all the way to St Pancras International buffer stops, but the
last section has a lower current capacity (about 2km from tunnel portal
is the neutral section IIRC).

TVM stops at the tunnel portal and lineside signals are provided from
there backed by KVB (a balise based ATP system).

--
John Alexander,

Remove NOSPAM if replying by e-mail
What are you working on now, John?
Brian

St Pancras International
 

"EE507" wrote in message
ps.com...
On Jul 30, 9:15 pm, John wrote:

TVM stops at the tunnel portal and lineside signals are provided from
there backed by KVB (a balise based ATP system).

Will E* remove AWS equipment as well as third rail contact gear at
some point?

It's interesting that the trains will continue to require separate
British, French and Belgian safety systems solely to approach the
respective termini (and French classic lines for certain sets of
course). Plenty of complexity there to add to running costs - I
wonder how quickly E* will remove the shoe gear...

Third-rail gear will be removed pretty sharpish, I imagine- it can be a real
pain if it decides to fail in the down position, as I discovered when one
took out some track-circuit- related equipment at the UK portal at the
beginning of a morning shift. They were still fixing it when I finished
eight hours later. There are some concrete blocks at the trackside some
distance before going into the tunnel, intended to knock off the offending
shoes, but this one managed to hang on long enough to spoil my morning.
Brian

St Pancras International
 

In article , BH Williams
writes

--
John Alexander,

Remove NOSPAM if replying by e-mail
What are you working on now, John?
Brian


I am at NR HQ working on standards, policies, scheme plan reviews, etc.
plus still doing some CTRL approvals.
--
John Alexander,

Remove NOSPAM if replying by e-mail

St Pancras International
 

BH Williams wrote:
Access to the northern end of HS1 is fairly limited, that to and from the
WCML being by the NLL, which presents pathing problems, from the MML being
by a single route from the Down Slow, and that from the ECML also being
single track. All these routes are provided with OCS.
Not entirely true - the MML-HS1 connection is not electrified.
I believe (though I'll have to check) that the station throat does have
lineside signals
That is true.

St Pancras International
 

On Mon, 30 Jul 2007, John wrote:

In article ,
writes

"BH Williams" wrote in message
...

Yes, it does. Currently, both TVM signalling and OCS start just east
of Fawkham Junction, somewhat to the north of Ashford.

Also, what is TVM and OCS?

OCS - Overhead Contact System - 25kV wires in the air. Three feeder
stations between London and Folkestone - the same as UK main lines
except that it can supply a higher current.

OCS goes all the way to St Pancras International buffer stops, but the
last section has a lower current capacity (about 2km from tunnel portal
is the neutral section IIRC).

Is it identical to standard British OHLE apart from the current capacity?
Presumably, the higher current is only needed for high-speed running, so
having less current near the terminals, where speeds are lower, is
presumably not a big deal.

tom

--
I KNOW WAHT IM TALKING ABOUT SO LISTAN UP AND LISTEN GOOD BECUASE ITS
TIEM TO DROP SOME SCIENTISTS ON YUO!!! -- Jeff K