Bakerloo Line beyond Harrow & Wealdstone
In article , Charles Ellson
writes
In other words, the resistors keep the rails at the +420V/-210V position
*unless* something else happens to alter this. Hence "loosely tied". But
at all times (absent a major short) the two rails are 630V apart.
They can be both at the same potential if there is a break between one
conductor rail feed and the substation (or only one of the pair of
switches feeding from the next section is closed) and you have a train
in section.
Or if the feed is broken upstream of the resistors.
Good point that I'd overlooked. Thanks.
--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:
|