"Ken" wrote in message
...
On Thu, 17 Nov 2005 19:40:14 GMT, "d" wrote:



Only the ones with insulators under them are live - the train runs on on
the
other two, and simply rubs the other ones to get its juice. One is +630v
and the other is -210v (or the +/- the other way round )

Isn't it 420v and 210v, making a difference of 630v (and I don't know
the polarity, either)?

The one in the middle is the negative and carries the lower voltage of 220v,
the one furthest from the platform is the positive and carries the higher
voltage of 440v for a combined total of 660v. The other two rails (the ones
not on insulators) do in fact have a slight electrical current in them to
work the signals (somewhere between 5 and 10 volts IIRC).
--
Cheers, Steve.
Change from jealous to sad to reply.