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IET (and other rolling stock?) can't transition from GWR ATP to ETCS on the move

Kentish RYS

Kentish RYS

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From the thread on GWML ETCS the fact IETs can't transition on the move from GWR ATP to ETCS came up and am curious but it isn't 100% relevant to that thread so I thought to make one to discuss here

JN114 said:
IETs can’t switch out of ATP on the move
Click to expand...

Does anyone know why this is the case?
The system is based on Belgian TBL and surely that can transition in and out on the move? Is it just that no one has bothered to produce the STM (Specific Transmission Module) that allows it to be integrated into ETCS for GWR ATP and it is different enough to no be a key to use the Belgian TBL one?
 
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JN114

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I perhaps over-simplified in the other thread, apologies

GWR 800/802 can’t have GW-ATP and ETCS enabled at the same time

With how the architecture is set up they’re like two faces of the same coin - GW-ATP has its own on train hardware; it isn’t emulated through ETCS like you might find with AWS/TPWS on a HEx 387

It may well be a specification shortfall - nobody asked for this capability so it wasn’t provided.

To switch between the different on train hardware, desk needs to be keyed out and drivers key used to operate a selector switch on back cab wall. This prevents you transitioning from one cab safety system to the other on the move.
 
C

class ep-09

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JN114 said:
I perhaps over-simplified in the other thread, apologies

GWR 800/802 can’t have GW-ATP and ETCS enabled at the same time

With how the architecture is set up they’re like two faces of the same coin - GW-ATP has its own on train hardware; it isn’t emulated through ETCS like you might find with AWS/TPWS on a HEx 387

It may well be a specification shortfall - nobody asked for this capability so it wasn’t provided.

To switch between the different on train hardware, desk needs to be keyed out and drivers key used to operate a selector switch on back cab wall. This prevents you transitioning from one cab safety system to the other on the move.
Click to expand...
At times , when ATP is faulty and cab from train hast to be driven from is where fault occurred, drivers are required to select ETCS on the back wall and run without ATP. Otherwise brakes won’t release.

There are speed limits and lines over which such train can run and in the cab the ATP speedo is “dead” but ETCS speedo (a display screen) is activated.

It happens sometimes on sets out-stabled away from Hitachi TMD’s, that were auxed off for the night and during morning prep ATP does not want to fully set itself up.
 
Kentish RYS

Kentish RYS

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JN114 said:
I perhaps over-simplified in the other thread, apologies

GWR 800/802 can’t have GW-ATP and ETCS enabled at the same time

With how the architecture is set up they’re like two faces of the same coin - GW-ATP has its own on train hardware; it isn’t emulated through ETCS like you might find with AWS/TPWS on a HEx 387

It may well be a specification shortfall - nobody asked for this capability so it wasn’t provided.

To switch between the different on train hardware, desk needs to be keyed out and drivers key used to operate a selector switch on back cab wall. This prevents you transitioning from one cab safety system to the other on the move.
Click to expand...
Thanks, so the HEx units have both through ETCS STM, what about the Crossrail/Elizabeth Line class 345?
 
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RandomTrainFan

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So this means
JN114 said:
I perhaps over-simplified in the other thread, apologies

GWR 800/802 can’t have GW-ATP and ETCS enabled at the same time

With how the architecture is set up they’re like two faces of the same coin - GW-ATP has its own on train hardware; it isn’t emulated through ETCS like you might find with AWS/TPWS on a HEx 387

It may well be a specification shortfall - nobody asked for this capability so it wasn’t provided.

To switch between the different on train hardware, desk needs to be keyed out and drivers key used to operate a selector switch on back cab wall. This prevents you transitioning from one cab safety system to the other on the move.
Click to expand...
So this means ETCS will need to go to reading before IETs can us it?
 
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JN114

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RandomTrainFan said:
So this means

So this means ETCS will need to go to reading before IETs can us it?
Click to expand...

No

I suspect removal of ATP from trackside would be the precursor to IETs using ETCS

That’s not likely to be until ETCS covers the entire former GW-ATP area
 
8

800301

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JN114 said:
No

I suspect removal of ATP from trackside would be the precursor to IETs using ETCS

That’s not likely to be until ETCS covers the entire former GW-ATP area
Click to expand...

With the amount of current AWS and ATP faults I wish they’d hurry up and get on with it
 
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