Proceedings 2002/2003 - IRSE

68
MIGRATION TO ERTMS ON EXISTING LINES
reasons for fitting ERTMS/ETCS on a high-speed
line as against a conventional line, or on a new line
as against an existing one undergoing refurbishment.
He will have to consider opening his network
to other operators and then possibly collecting
revenue from new sources. He will also have to look
at possible extra train paths, because ERTMS/ETCS
brings extra line capacity. ERTMS/ETCS will be a
very interesting “alternative to concrete” (being
much cheaper).
A railway operator has various requirements:
• he may want to run faster trains;
• he may want a simpler, more reliable and available
ATP than the juxtaposition that was the only
way before ERTMS/ETCS;
• he may want to reduce ATP costs, space
requirements, etc.
As operators tend to have different requirements
depending on their background and on the lines and
infrastructure they plan to operate, they will
consider Specific Transmission Modules (STMs).
The “pure” STM concept as defined by the
ERTMS/ETCS specifications will not necessarily be
the optimum solution for a given operator. Other
possibilities exist, and must be analysed and priced
to enable an adequate decision to be taken (see
Figure 5). They include, for example, use of a
gateway device between an existing national ATP
architecture and the on-board ERTMS/ETCS.
Another solution planned in a number of cases is the
“bi-mode” (or “bi-standard”) EVC concept. This
saves hardware and software, especially for the
main computer, as well as improving technical
issues such as management of reaction times and
design convenience.
money for it, the space to fit the equipment and
whatever else may be involved, with the risk of
having to do a major refurbishment not otherwise
required, especially in the driver’s cab.
• Operation costs, including signalling costs
transferred from ground to train. There are also
responsibility issues when infrastructure and
operator are separate, such as who is responsible
and who has to pay when trains are
delayed.
• Maintenance and training relating to ERTMS/
ETCS system and its new technologies, such
as radio, will also involve new costs not
encountered before.
There may be other points against ERTMS/ETCS
that should be discussed. These questions should
certainly be asked, and they must be weighed with
the points for the system in order to arrive at a
correct decision.
WHERE ARE WE GOING?
Following the phases of specification development
and extensive testing, work on ERTMS/ETCS
is now very active. Many commercial projects have
already been commissioned or are being designed
and implemented, and many more are in the
pipeline.
Figure 6 – Current Commercial Projects
with ERTMS/ETCS
Figure 5 – Volume of Trainborne Equipment –
Decision Square
As to whether ERTMS/ETCS is not simply "one more
trainborne ATP system", the problem is, of course,
concentrated on board the train, so that it affects
train operators and integrated railways.
Nevertheless infrastructure owners have a similar
concern because they also face problems of
installation of dual equipment and compatibility
issues.
There are a number of cost issues, as follows:
• Installation costs: for ERTMS/ETCS, being a
new system, there is the issue of finding the
There are, however, a number of different trends,
arising from railways' different priorities and reasons
for choosing ERTMS/ETCS.
Countries in the centre of Europe, and smaller
countries generally, tend to emphasise interoperability
because they have a lot of international traffic,
with many trains in transit or at least starting or
finishing their journeys outside the borders.
In other countries where there is currently no ATP,
or where the local system is becoming obsolete, the
main requirement to go to ERTMS/ETCS arises from
safety.
In places where rail faces strong air or road
competition, or where time-keeping is considered to
be of paramount importance, the main requirements
are for availability and reliability. This is especially the
case in Switzerland, as most people might imagine,
but it is also true in Spain, where the rule on the
high-speed line network is that the passenger will