In message , Clive D. W. Feather
writes
There are a lot of complex electrical issues with dual-electrified
track. It isn't just a matter of sticking down some third rail,
particularly since in this case you'd be extending those issues to the
main ECML tracks as well. I'd expect fixing them to cost at least 5
million pounds based on current signalling prices. If this sort of
problem is rare, it's not going to be economically justifiable.
Surely the equipment already exists that can cope with signalling in
dual (25kV & 750V) areas, why so expensive? Or are there other issues?
--
Clive