I have mentioned in passing that as the class 700 entered service new challenges would raise their heads and the next hurdle is getting our ‘ERTMS’ signalling system into passenger use. Now what is ERTMS?
ERTMS, if you did not know, stands for European Railway Traffic Management system and is made up of a few parts but the two fundamental parts are GSM-R and ETCS.
These two parts form the basis of a new signalling system that will control the trains in the UK in the future.
GSM-R is the radio system that trains in the UK have been converted to (or being converted to), it works on the same sort of frequencies as your mobile phone and is therefore capable of transferring data and voice communication. The data aspect is very important as through this link information is shared between the signalling system and the train and enables the whole system to function.
ETCS is made up of various levels, the most common and user friendly is ETCS Level 2.
Level 2 is what currently is being installed in the UK and for this blog post is the only level to talk about.
ETCS level 2 works with traditional track circuits but replaces the needs for line side signage and signals as it is transmitted to the cab through ‘balises’ and the GSM-R. A Balise is a piece of plastic in the track that contains information for the train, the train reads this through a ‘balise antenna’ fitted to the underside of the train that using radiation energises the balise – there is no power to the balise in the track. For those of you who travel through London on GTR services the little yellow balises are obvious in the 4 foot of the track.
Recently in the industry a lot has been mentioned of ETCS and Brexit but it bares remembering that more countries outside the European union (including a planned application in the USA) use ETCS than those inside and that is due to the fact that it is a proven system ready to run off the shelf. Why would a country develop a system from scratch when one exists? What Brexit may enable is the UK to avoid certain rules such as converting to KPH/Kilometres, however we will see.
There are two types of ETCS level 2 currently planned in the UK, they are called ‘Overlaid’ and ‘non overlaid’. GTR’s ETCS London section will be overlaid. All this means is the traditional signalling remains and ETCS is overlaid on top of it. This will mean the signals will change colour as they do today but with ETCS giving the commands.
Non overlaid is as you image and that is the complete removal of signals, exactly as the UK’s first application, on the Cambrian, was done.
So what does that mean for modelling? Well if your modelling an ETCS section it means you now have to model ‘marker boards’.
Looking below (ignoring the STOP board which is for a level crossing) imagine the yellow and blue board on the left is a signal, ETCS gives the train a ‘movement authority’ between these marker boards.
So if you passed one of these marker boards without an adequate movement authority you have committed an age old SPAD (signal passed at danger). The system however negates risks in SPADs by continually supervising the driver. So the system is fundamentally more safer than what we operate today.
In a nutshell that is how is works, using mobile data and track balises the system will plot the course between marker boards and send this information to the driver in the cab.
And what has that got to do with me being in Wales?
As I mentioned above the Cambrian line was the first implementation of ETCS level 2 in the UK. The national program delivering ETCS across the UK has designed a training course for the Operations ETCS project managers on various railways to go to the Cambrian and learn to drive the system to a level that they are then able to go back to their parent company and become competent to provide training etc on the system.
This course was the first one and was split into two segments, a week in the classroom and three days practical handling on the Cambrian – this is where still holding a full UK train driving licence comes in handy!
Here is the cab of a 158 showing the onboard ‘face’ of the equipment the DMI (driver machine interface) any ETCS train will have a DMI to show the information to driver.
The course was great and you will be pleased to know I passed with flying colours, driving under ETCS is a doddle. For example on the digital speedo curve, can you see the white ‘hook’ that tells me how fast I can go, if I go over it the train brakes for me, that is how the speed supervision works. As you come up to the end of an authority as mentioned above the hook starts to descend and if you do not brake in time again the train brakes for you.
The only issue with being in North Wales for the best part of two weeks was completely falling in love with the area and now my mind is running with 70s Cambrian layout plans and looking at house prices on Primelocation and wondering why on earth living in Kent costs so much.
The weekend in between gave me ample opportunity to explore the preserved railways and get my first true taste of narrow gauge. It was mega deviant and mega awesome.
I also bagged a visit to the Llangollen railway and what a place that was…
I leave you with a final photo of myself and 158 836 at Machynlleth, my first mainline diesel, another first was being signalled by GWR lower quadrants at Shewesbury, all in all not a bad work course for a change!
This was a very basic little bit of information on ETCS and I hope it gives someone some benefit and interest,
Thanks folks and modelling to resume soon,