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[email protected] March 31st 07 03:26 PM

London Bridge signals question
 
Was at London Bridge the other day platform 6 waiting for a Bedford
train watching trains pass through the platform and noticed that
signal L100 which appears as a 2 aspect but actually capable of
showing double yellow had a indicator box at side which was showing CD
this then changed to RA the signal was showing the same aspects during
the time the sign changed. anyone explain what this was etc.


Jack Taylor March 31st 07 03:45 PM

London Bridge signals question
 
wrote:
Was at London Bridge the other day platform 6 waiting for a Bedford
train watching trains pass through the platform and noticed that
signal L100 which appears as a 2 aspect but actually capable of
showing double yellow had a indicator box at side which was showing CD
this then changed to RA the signal was showing the same aspects during
the time the sign changed. anyone explain what this was etc.


The signal in question is one of the new style that uses light emitting
diodes (LEDs) for display, rather than individual lenses and bulbs.
Therefore a three-aspect traditional colour light signal can be replaced
with a single lens using LEDs. A four-aspect requires two LED displays, in
order to accommodate the two yellow aspects.

CD = close doors. Instruction to the driver of single-manned trains,
initiated by a plunger pressed by platform staff, that they are ready to
commence the departure procedure.

RA = right away. Instruction to the driver of single-manned trains,
initiated by a plunger pressed by platform staff, that the doors are closed,
all of the door open lights are extinguished and the train is clear to
depart.



Peter Masson March 31st 07 03:46 PM

London Bridge signals question
 

wrote in message
oups.com...
Was at London Bridge the other day platform 6 waiting for a Bedford
train watching trains pass through the platform and noticed that
signal L100 which appears as a 2 aspect but actually capable of
showing double yellow had a indicator box at side which was showing CD
this then changed to RA the signal was showing the same aspects during
the time the sign changed. anyone explain what this was etc.

Most of ther trains which use this platform are Driver Only Operated, so
platform staff have to assist in dispatching trains (see other thread). When
station work is complete, the dispatcher turns a switch which turns the 'CD'
display on, telling the driver to 'Close Doors'. When the doors are closed
and the orange indicator lights on the train have akll gone out, the
dispatcher will turn the switch, to extinguish the 'CD' display and
illuminate the 'RA', telling the driver 'Right Away'.

Is the 'RA' indicator interlocked with the signal, so that it cannot be
displayed if the signal is at red?

Presumably the signal itself uses an LED display, so that the upper head can
display green or yellow, and the lower head yellow or red, and the signal as
a whole can display all four aspects R, Y, YY, and G.

Peter



[email protected] March 31st 07 03:57 PM

London Bridge signals question
 
On 31 Mar, 16:46, "Peter Masson" wrote:
wrote in message

oups.com... Was at London Bridge the other day platform 6 waiting for a Bedford
train watching trains pass through the platform and noticed that
signal L100 which appears as a 2 aspect but actually capable of
showing double yellow had a indicator box at side which was showing CD
this then changed to RA the signal was showing the same aspects during
the time the sign changed. anyone explain what this was etc.


Most of ther trains which use this platform are Driver Only Operated, so
platform staff have to assist in dispatching trains (see other thread). When
station work is complete, the dispatcher turns a switch which turns the 'CD'
display on, telling the driver to 'Close Doors'. When the doors are closed
and the orange indicator lights on the train have akll gone out, the
dispatcher will turn the switch, to extinguish the 'CD' display and
illuminate the 'RA', telling the driver 'Right Away'.

Is the 'RA' indicator interlocked with the signal, so that it cannot be
displayed if the signal is at red?

Presumably the signal itself uses an LED display, so that the upper head can
display green or yellow, and the lower head yellow or red, and the signal as
a whole can display all four aspects R, Y, YY, and G.

Peter


Thanks must go to the back of the class should have worked it out.


Jonathan Morton March 31st 07 04:59 PM

London Bridge signals question
 
"Peter Masson" wrote in message
...

Presumably the signal itself uses an LED display, so that the upper head
can
display green or yellow, and the lower head yellow or red, and the signal
as
a whole can display all four aspects R, Y, YY, and G.


I think I read somewhere that both heads can display red, but that normally
the lower one is used for red. The upper head can be used in emergency to
display red if the lower one has failed for any reason. BICBW.

Regards

Jonathan



G March 31st 07 09:59 PM

London Bridge signals question
 
On Sat, 31 Mar 2007 15:45:52 GMT, "Jack Taylor"
wrote:

RA = right away. Instruction to the driver of single-manned trains,
initiated by a plunger pressed by platform staff, that the doors are closed,
all of the door open lights are extinguished and the train is clear to
depart.


I've seen RA indicators at Manchester Victoria, where there are no
single manned trains. Are they serving the same purpose?

And, while I'm in obvious (but not to me) question mode, above the
signals are larger ones that occasionally display U B in two boxes.
Why?

Clive D. W. Feather March 31st 07 10:27 PM

London Bridge signals question
 
In article , G
writes
I've seen RA indicators at Manchester Victoria, where there are no
single manned trains. Are they serving the same purpose?

And, while I'm in obvious (but not to me) question mode, above the
signals are larger ones that occasionally display U B in two boxes.
Why?


They are telling the driver which route he's going to take (so he knows
which speed restrictions apply and which is the next signal to obey).
Normally I would suggest it's short for "Up Bolton", but Quail tells me
that all directions from Man Vic are Down, and there's no Bolton line
leaving the station.

["U" is normally "Up". Going "wrong road" is normally shown with an
"X".]

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:

G March 31st 07 10:41 PM

London Bridge signals question
 
On Sat, 31 Mar 2007 23:27:41 +0100, "Clive D. W. Feather"
wrote:

And, while I'm in obvious (but not to me) question mode, above the
signals are larger ones that occasionally display U B in two boxes.
Why?


They are telling the driver which route he's going to take (so he knows
which speed restrictions apply and which is the next signal to obey).
Normally I would suggest it's short for "Up Bolton", but Quail tells me
that all directions from Man Vic are Down, and there's no Bolton line
leaving the station.

["U" is normally "Up". Going "wrong road" is normally shown with an
"X".]


No, it's definitely not Bolton. The indicators are on the eastbound
signals.

Jack Taylor March 31st 07 11:14 PM

London Bridge signals question
 
G wrote:
On Sat, 31 Mar 2007 23:27:41 +0100, "Clive D. W. Feather"
wrote:

And, while I'm in obvious (but not to me) question mode, above the
signals are larger ones that occasionally display U B in two boxes.
Why?


They are telling the driver which route he's going to take (so he
knows which speed restrictions apply and which is the next signal to
obey). Normally I would suggest it's short for "Up Bolton", but
Quail tells me that all directions from Man Vic are Down, and
there's no Bolton line leaving the station.

["U" is normally "Up". Going "wrong road" is normally shown with an
"X".]


No, it's definitely not Bolton. The indicators are on the eastbound
signals.


I can't help you on that one, either. According to Quail, the eastbound
lines are Up/Down Rochdale Fast/Slow. I haven't got an old Quail to hand
but, pre-Metrolink, the Bury lines might have been Up/Down Bury - these days
they are simply known as Inbound and Outbound and are not governed by the
same signalling system, in any case.



[email protected] April 1st 07 02:44 AM

London Bridge signals question
 
On 31 Mar, 23:27, "Clive D. W. Feather" c...@on-the-
train.demon.co.uk wrote:

They are telling the driver which route he's going to take (so he knows
which speed restrictions apply and which is the next signal to obey).


And normally known as 'theatre type route indicators'. Except that in
the report into an accident at Euston in 1949, the inspecting officer
describes them as 'a route indicator of the music hall type'.

Was this a generally used term at one time, or is the inspecting
officer simply confused?

The report is available on the Railways Archive site, at:

http://tinyurl.com/3xkk2n

The reference is in paragraph 2.


Clive D. W. Feather April 1st 07 09:08 AM

London Bridge signals question
 
In article .com,
writes
And normally known as 'theatre type route indicators'. Except that in
the report into an accident at Euston in 1949, the inspecting officer
describes them as 'a route indicator of the music hall type'.

Was this a generally used term at one time, or is the inspecting
officer simply confused?


This kind of indicator was originally used in music halls or theatres to
indicate which act was being shown; the railway then appropriated them.
So both "music hall type" and "theatre" are reasonable names, though the
former probably went out of use as the music halls did.

Technically they are "alphanumeric indicators meeting sighting
requirement class 2", if I recall correctly. Stencil indicators meet
sighting requirement class 3.

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:

Neil Williams April 1st 07 09:30 AM

London Bridge signals question
 
On Sat, 31 Mar 2007 22:59:14 +0100, G
wrote:

I've seen RA indicators at Manchester Victoria, where there are no
single manned trains. Are they serving the same purpose?


Yes. For whatever reason (perhaps repeated "ding-ding-and-away" SPADs
or something), it's been decided that the traditional approach of the
guard giving the RA isn't appropriate at that station, so instead the
guard closes the doors then shows a green flag to the platform staff,
who then activate the RA and the train departs.

I think Manc Picc has it as well.

Neil

--
Neil Williams
Put my first name before the at to reply.

Jonathan Morton April 1st 07 12:11 PM

London Bridge signals question
 
"Clive D. W. Feather" wrote in message
...
In article .com,
writes
And normally known as 'theatre type route indicators'. Except that in
the report into an accident at Euston in 1949, the inspecting officer
describes them as 'a route indicator of the music hall type'.

Was this a generally used term at one time, or is the inspecting
officer simply confused?


This kind of indicator was originally used in music halls or theatres to
indicate which act was being shown; the railway then appropriated them. So
both "music hall type" and "theatre" are reasonable names, though the
former probably went out of use as the music halls did.


That's interesting. I'd always assumed that the name came from the fact that
the usual shape of the display (rectangular, and shaded) looked vaguely like
a stage as it appears in theatre when the house lights are down - I always
wanted the ones at Waterloo to have curtains which would dramatically part
to reveal... "ta-da...MT" or whatever.

Another illusion shattered.

Technically they are "alphanumeric indicators meeting sighting requirement
class 2", if I recall correctly. Stencil indicators meet sighting
requirement class 3.


Linking in with the other current thread on signal visibility, I presume
that class 1 is "8 seconds at line speed on the road", class 2 is less
strict than that (but still used in cases where they need to be visible from
a moving train), and class 3 is only for cases where the view will be from a
train standing at a platform waiting for the RA. Is that right?

Regards

Jonathan



[email protected] April 1st 07 12:50 PM

London Bridge signals question
 
On 1 Apr, 13:11, "Jonathan Morton"

That's interesting. I'd always assumed that the name came from the fact that
the usual shape of the display (rectangular, and shaded) looked vaguely like
a stage as it appears in theatre when the house lights are down - I always
wanted the ones at Waterloo to have curtains which would dramatically part
to reveal... "ta-da...MT" or whatever.


I thought it was something to do with the etymology of 'theatre',
which is from the Greek "to behold". We live and learn...

On the subject of theatre type indicators, was there anywhere else,
other than Liverpool Street, that used them with non-alphanumeric
indications? At the ends of the Liverpool Street platforms they used
to display a horizontal line of lights, each light representing a
route from left to right, with a light above and below the route set.
So you had a single horizontal line of lights, except for the set
route which had a vertical line of three.


Clive D. W. Feather April 1st 07 04:42 PM

London Bridge signals question
 
In article , Jonathan Morton
writes
Linking in with the other current thread on signal visibility, I presume
that class 1 is "8 seconds at line speed on the road", class 2 is less
strict than that (but still used in cases where they need to be visible from
a moving train), and class 3 is only for cases where the view will be from a
train standing at a platform waiting for the RA. Is that right?


GK/RT0031 says:

B27.5.1 Performance category 1 equipment
All equipment meeting the requirements of performance category 1 shall
be designed to be readable at speeds up to 125 mph.

B27.5.2 Performance category 2 equipment
With the exception of the banner repeating signal, equipment which meets
the requirements of performance category 2 shall be designed to be used
only where the approach speed of trains requiring to read the indication
does not exceed 60 mph.

B27.5.3 Performance category 3 equipment
With the exception of independent position light signals which are
pre-set by a main route, equipment which does not exceed the
requirements of performance category 3 shall be designed to be used only
where there is no requirement for the aspect / indication to be read at
a speed exceeding 15 mph. For this purpose, it is assumed that 15 mph
will not be exceeded by:
a) movements contained within the confines of a yard or siding
b) movements starting from rest, or virtually at a stand at a main stop
aspect
c) movements proceeding under the authority of a position light aspect.

B27.5.4 Performance category 4 equipment
Semaphore main signals shall be designed to be readable at speeds up to
100 mph.

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:

Clive D. W. Feather April 1st 07 05:12 PM

London Bridge signals question
 
In article . com,
writes
On the subject of theatre type indicators, was there anywhere else,
other than Liverpool Street, that used them with non-alphanumeric
indications? At the ends of the Liverpool Street platforms they used
to display a horizontal line of lights, each light representing a
route from left to right, with a light above and below the route set.
So you had a single horizontal line of lights, except for the set
route which had a vertical line of three.


I think you're misremembering. There were platforms with two routes out,
either left over a crossover and to the starting signal of the next
platform on the left, or ahead and then over a crossover beyond that
signal. These were shown with theatre indicators displaying:

o o
o o o o o o o o o o
o o
o
o
o
o

As for other places, signal P423 on the Down Fast approaching
Peterborough used to have two theatre indicators that were used to
simulate "feathers" - they showed a diagonal line or a horizontal line
for the two routes to the left and the three to the right. This was an
experiment, and they've now been replaced by four normal feathers plus a
theatre to one side that shows (IIRC) "B" for "bay" instead of the third
route to the right.

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:

WZR April 1st 07 06:47 PM

London Bridge signals question
 
On Sun, 1 Apr 2007 10:08:13 +0100, Clive D. W. Feather wrote:

In article .com,
writes
And normally known as 'theatre type route indicators'. Except that in
the report into an accident at Euston in 1949, the inspecting officer
describes them as 'a route indicator of the music hall type'.

Was this a generally used term at one time, or is the inspecting
officer simply confused?


This kind of indicator was originally used in music halls or theatres to
indicate which act was being shown; the railway then appropriated them.
So both "music hall type" and "theatre" are reasonable names, though the
former probably went out of use as the music halls did.

Technically they are "alphanumeric indicators meeting sighting
requirement class 2", if I recall correctly. Stencil indicators meet
sighting requirement class 3.


That is the current terminology, which is intended to be technology-independent.

These indicators are now made in fibre-optic form with a single lamp
illuminating many dots via a bundle of fibres, but earlier versions had a
(usually 7 x 7) matrix of "Pygmy" lamps. Depending upon the particular
requirements of each one, each lamp could be used in several indications and the
wiring arrangements could be rather complex and difficult to set up if lamp
proving was required. As well as the semi-colloquial "Theatre", these were also
known officially as "Multi-lamp Route Indicators".

Stencils were different again, with a lamp showing through a mask, behind a
piece of frosted glass, so the indication is hidden until illuminated. Most
people will probably have seen something similar at pedestrian crossings, the
illuminated "WAIT" signs operate on the same principle.

As with MLRIs, Stencils are now (usually) newly provided in FO form, the only
difference between these two types is now their size (physical and indication),
and the number of indications which can be accomodated within a single box.

--
WZR

GMac April 2nd 07 12:03 PM

London Bridge signals question
 
On 1 Apr, 18:12, "Clive D. W. Feather"
wrote:
In article . com,
writes

On the subject of theatre type indicators, was there anywhere else,
other than Liverpool Street, that used them with non-alphanumeric
indications? At the ends of the Liverpool Street platforms they used
to display a horizontal line of lights, each light representing a
route from left to right, with a light above and below the route set.
So you had a single horizontal line of lights, except for the set
route which had a vertical line of three.


I think you're misremembering. There were platforms with two routes out,
either left over a crossover and to the starting signal of the next
platform on the left, or ahead and then over a crossover beyond that
signal. These were shown with theatre indicators displaying:

o o
o o o o o o o o o o
o o
o
o
o
o

As for other places, signal P423 on the Down Fast approaching
Peterborough used to have two theatre indicators that were used to
simulate "feathers" - they showed a diagonal line or a horizontal line
for the two routes to the left and the three to the right. This was an
experiment, and they've now been replaced by four normal feathers plus a
theatre to one side that shows (IIRC) "B" for "bay" instead of the third
route to the right.

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:


Something similar was in place at Lancaster (up station home signal,
just to the north of the Carlisle bridge) for quite a while, as there
are 6 possible routes available from that - bays 1&2, down platform
loop (3, turnback only), up fast, up main platform (4) and up platform
loop (5). That replaced a pair of theatre indicators, one of which
only lit if the route was towards either of the bays.

GM



Railsigns.co.uk April 9th 07 02:24 PM

London Bridge signals question
 
On Mar 31, 10:59 pm, G wrote:
I've seen RA indicators at Manchester Victoria, where there are no
single manned trains. Are they serving the same purpose?

And, while I'm in obvious (but not to me) question mode, above the
signals are larger ones that occasionally display U B in two boxes.
Why?


According to the 1998 resignalling notice, there is no route
indication "UB" at Manchester Victoria. The indications used there
a

"UF" - Up Rochdale Fast
"DS" - Down Rochdale Slow

"UB" is used on a shunting signal at Philips Park South Junction to
denote "Up Baguley".

--------------------------------------------------------------------
Railway Signs and Signals of Great Britain: http://
www.railsigns.co.uk/
Mileposts: http://www.railsigns.co.uk/other/milepost1/milepost1.html


Railsigns.co.uk April 9th 07 02:34 PM

London Bridge signals question
 
On Mar 31, 5:59 pm, "Jonathan Morton"
wrote:

"Peter Masson" wrote in message


Presumably the signal itself uses an LED display, so that
the upper head can display green or yellow, and the lower
head yellow or red, and the signal as a whole can display
all four aspects R, Y, YY, and G.


I think I read somewhere that both heads can display red,
but that normally the lower one is used for red. The upper
head can be used in emergency to display red if the lower
one has failed for any reason. BICBW.


That is wrong. The signals used on the Manchester South scheme can do
that, but they aren't LED type.

--------------------------------------------------------------------
Railway Signs and Signals of Great Britain: http://
www.railsigns.co.uk/
Mileposts: http://www.railsigns.co.uk/other/milepost1/milepost1.html



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