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Wire height standards
Author: Ernest H. Robl
Date: 08-17-2009 - 18:37
As someone has already mentioned the Chunnel: The Chunnel
vehicle shuttle trains have unusually high equipment -- at
least for European standards -- so the wire the Chunnel is
actually substantially higher than the normal European
standards.
Electric locomotives (and of course the Eurostar passenger
trains) have to have special dual heigh pantographs, which
allow them to operate on both the normal height European
wire and the extra high Chunnel catenary (also used in the
terminal areas on both sides of the Chunnel).
The dampening equipment that keeps the pantographs in contact
with the wire has two different modes, which are automatically
set by wayside transponders, as the trains transition to and
from the higher catenary. The electric locomotives -- even
those used to pull the dedicated vehicle shuttle trains -- are
of standard height, so that they can also operate outside the
special Chunnel domain under lower wires.
For future U.S. electrification, there will need to be at least
two catenary height standards -- one for lines with only
passenger service and normal height freight equipment and
one for lines on which tall equipment, such as double-stacks
operates. Again, the multiple wire height problem has already
been solved on the Chunnel line.
The higher wire standard would be somewhat more expensive -- but
would only be needed in some areas. For a true high-speed line,
the lower catenary standard would work fine. It would only be
on some sections of existing tracks in and around cities that
you would need the higher standard -- in the beginning. Of
course, if you electrify cross-country freight main lines, some
of these would need the higher catenary to handle double-stack
trains.
Electrification (to modern global standards) has many benefits
beyond high-speed rail. Not only can the power come from many
different sources, but you can operate through long tunnels
which cannot be used by any types of motive power that produces
emissions. The longest U.S. tunnels (Cascade, Moffat, Flathead)
are essentially at the limits of length that can be ventilated
between trains. All of them are major choke points (no pun
intended) on their respective lines, because of the time needed
to vent the exhaust fumes after each train.
Electrification also provides much better accelleration for all
types of trains.
-- Ernest
vehicle shuttle trains have unusually high equipment -- at
least for European standards -- so the wire the Chunnel is
actually substantially higher than the normal European
standards.
Electric locomotives (and of course the Eurostar passenger
trains) have to have special dual heigh pantographs, which
allow them to operate on both the normal height European
wire and the extra high Chunnel catenary (also used in the
terminal areas on both sides of the Chunnel).
The dampening equipment that keeps the pantographs in contact
with the wire has two different modes, which are automatically
set by wayside transponders, as the trains transition to and
from the higher catenary. The electric locomotives -- even
those used to pull the dedicated vehicle shuttle trains -- are
of standard height, so that they can also operate outside the
special Chunnel domain under lower wires.
For future U.S. electrification, there will need to be at least
two catenary height standards -- one for lines with only
passenger service and normal height freight equipment and
one for lines on which tall equipment, such as double-stacks
operates. Again, the multiple wire height problem has already
been solved on the Chunnel line.
The higher wire standard would be somewhat more expensive -- but
would only be needed in some areas. For a true high-speed line,
the lower catenary standard would work fine. It would only be
on some sections of existing tracks in and around cities that
you would need the higher standard -- in the beginning. Of
course, if you electrify cross-country freight main lines, some
of these would need the higher catenary to handle double-stack
trains.
Electrification (to modern global standards) has many benefits
beyond high-speed rail. Not only can the power come from many
different sources, but you can operate through long tunnels
which cannot be used by any types of motive power that produces
emissions. The longest U.S. tunnels (Cascade, Moffat, Flathead)
are essentially at the limits of length that can be ventilated
between trains. All of them are major choke points (no pun
intended) on their respective lines, because of the time needed
to vent the exhaust fumes after each train.
Electrification also provides much better accelleration for all
types of trains.
-- Ernest
