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Great Western Signalling and ERTMS

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gwr4090

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In the original plans for the Great Western, I think the (obsolete) GW APT between Paddington and Bristol was due to be replaced by ERTMS (ETCS Level 2 ?) as an overlay to the existing signalling by the end of 2017. This has obviously not happened, so I guess that the Class 800s have been fitted with GW APT ? I believe that the Class 387 (like the 165/166) is not fitted with APT. But it appears that the Crossrail Class 345s now require ERTMS at least in the Heathrow tunnels, hance the imminent tests with a Class 345 to Heathrow. Presumably ERTMS will eventually be extended elsewhere on the GWML. WIll it be needed before the Class 387 use the main lines at 110mpm ?
 
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rebmcr

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Class 345 operation in the Heathrow tunnels will use TPWS+ until ERTMS is installed and comissioned.

I believe there is no space for ATP in the Class 80x equipment bays, I'm not sure what they will use in the interim — perhaps just AWS & TPWS.
 

swt_passenger

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It was the Crossrail stock that was reported to have no room for GW ATP, and the problem was that GW ATP was the only system in place on the Heathrow branch. So as an alternative option for Crossrail some sort of ERTMS has had to be fitted to that branch.
 

LNW-GW Joint

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The GWML is having ETCS fitted (by Alstom) as far as Reading (as well as to Heathrow).
There is no plan yet to roll it out further, so GW ATP will have to continue until it is.
 

Filton Bank

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Class 345 operation in the Heathrow tunnels will use TPWS+ until ERTMS is installed and comissioned.

I believe there is no space for ATP in the Class 80x equipment bays, I'm not sure what they will use in the interim — perhaps just AWS & TPWS.
GWR 800s are fitted with both ATP and ETCS, but only one is in use at a time. There's a selecton switch on the cab back wall.
 

rebmcr

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The GWML is having ETCS fitted (by Alstom) as far as Reading (as well as to Heathrow).
There is no plan yet to roll it out further, so GW ATP will have to continue until it is.

Is that going to be ready for the TfL Rail 345s to replace Connect?
 

100andthirty

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I might be wrong, but my understanding is that ETCS is fitted solely on the Heathrow branch and that TPWS has been enhanced out to Reading - basically fitting it at more signals and a few more speed traps. ETCS to Reading was the original plan but that plan ran out of time (and possibly cost). And class 800 does have GW ATP as the photo on this thread and photos from other places clearly show
 

coppercapped

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I might be wrong, but my understanding is that ETCS is fitted solely on the Heathrow branch and that TPWS has been enhanced out to Reading - basically fitting it at more signals and a few more speed traps. ETCS to Reading was the original plan but that plan ran out of time (and possibly cost). And class 800 does have GW ATP as the photo on this thread and photos from other places clearly show
That is also my understanding of the current situation.
 

jdxn

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Class 345 operation in the Heathrow tunnels will use TPWS+ until ERTMS is installed and comissioned.

I believe there is no space for ATP in the Class 80x equipment bays, I'm not sure what they will use in the interim — perhaps just AWS & TPWS.

The Class 345 will use ECTS Level2 as an overlay in Full Supervision mode from airport junction to the terminals. When on the mains or reliefs from Airport Jn to London ECTS will run as Level NTC (national train control) which means that it will use TPWS/AWS. The transition between levels will (should) take place automatically as the train passes balises on the approach to the transition point. This is already installed/being commissioned for the first tests of the Crossrail stock next year.
 

SpacePhoenix

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It was the Crossrail stock that was reported to have no room for GW ATP, and the problem was that GW ATP was the only system in place on the Heathrow branch. So as an alternative option for Crossrail some sort of ERTMS has had to be fitted to that branch.

Is there any good photos anywhere that show the relative sizes of the on-board kit (not the stuff mounted underneath to read balises/beacons/magnets) for ATP, TPWS and ECTS?
 
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MarkyT

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The Class 345 will use ECTS Level2 as an overlay in Full Supervision mode from airport junction to the terminals. When on the mains or reliefs from Airport Jn to London ECTS will run as Level NTC (national train control) which means that it will use TPWS/AWS.

That means that the main ETCS computer on board, the EVC (European Vital Computer), and the MMI (Man Machine Interface) will emulate the traditional TPWS/AWS behaviour without the need for a separate controller and traction/braking interface. The equipment talks to the legacy track transponders by means of a UK-bespoke STM (Specific Transmission Module).
 

HowardGWR

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MarkyT good job we've got you and others on this board. My eyes glaze over on this stuff.
 

jdxn

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doh - sorry! ETCS not ECTS!

For those interested the following RSSB publication is a good introduction to the whole thing. Early on there are a couple of schematics, one for the 'system' and one for the on board train equipment that MarkyT mentioned. It also shows how the different driving modes FS, OS etc are used.

https://www.rssb.co.uk/rgs/casdocs/RSSB-ERTMS-OC Iss 2.pdf
 

D365

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Is there any good photos anywhere that show the relative sizes of the on-board kit (not the stuff mounted underneath to read balises/beacons/magnets) for ATP, TPWS and ECTS?

Do you mean cab equipment? Other than that I’m not sure how much of it is in the public domain.
 

SpacePhoenix

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The stuff that would go in equipment bays. I believe that on the Cambrian that the ETCS installed there is the size of a filing cabinet. Now that a few years have passed it's possible that the electronics tech might have improved possibly allowing the electronics behind it to be smaller
 

Railsigns

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This is a photo of the ERTMS equipment on board a Class 158. It is indeed the size of a filing cabinet.

ertms158.jpg
 

TwistedMentat

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This is a photo of the ERTMS equipment on board a Class 158. It is indeed the size of a filing cabinet.

ertms158.jpg

Damn that's a lot of space. I would have expected these days for it to be a box or two. But I guess as a relatively low run sort of thing and with the space available on a train there's no massive pressure to make it tiny. This from the perspective of a software developer.
 

rebmcr

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Damn that's a lot of space. I would have expected these days for it to be a box or two. But I guess as a relatively low run sort of thing and with the space available on a train there's no massive pressure to make it tiny. This from the perspective of a software developer.

Yeah, from my perspective (network administrator), there is a LOT of free space behind those blanking plates. It gives a ton of flexibility though, given that the Cambrian is the ERTMS testbed.
 
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