Re: Overhead

["Chris Downs" <cvdowns@ozemail.com.au>]

Tezza <tezza2000@dingoblue.net.au> wrote in message
3a2af0a4$0$19429$7f31c96c@news01.syd.optusnet.com.au">news:3a2af0a4$0$19429$7f31c96c@news01.syd.optusnet.com.au...
>
> "David Johnson" <trainman@ozemail.com.au> wrote in message
> 1103_975855188@retard1">news:1103_975855188@retard1...
> > On Mon, 4 Dec 2000 00:25:52 +1100, "Tezza" <tezza2000@dingoblue.net.au>
> wrote:
> > > This may put me in the dumb question brigade, but.......
> > >
> > > I've been running out Penrith way for years, but musta had the
blinkers
> on.
> > > Today I noticed, on both the up and down between Penrith and St Marys,
an
> > > extra wire running alongside the overhead. It would have a wire
joining to
> the
> > > overhead at infrequent intervals, anywhere from about 30 metres to
over
> 100
> > > metres. Does anyone know what it is/what it's for? I can email a
couple of
> > > photos if it will help.
> >
> > It is a feeder wire.  It runs in parallel to the catenary to supply
extra
> current with lower voltage drop.
>
> Thanks, how long has it been there?

According to Dornan's & Henderson's "The Electric Railways of New South
Wales":

".......Due to the shortage of funds the scheme (sic western
quadruplication) was cutback
in scale so that the planned quadruplication through to Doonside did not
eventuate, but
provision for quadruplication along the entire route from Blacktown to
Penrith was made
by B.I.C.C. by the installation of portal structures above the two existing
running lines
with cantilever extensions added to either side, beneath which could be
built the
additional two tracks.  B.I.C.C. installed a catenary wire from the
cantilever extensions
to give sufficient copper area for current supply to the existing two tracks
and to be in
position for the future additional two lines."

That's the origin of the extra wire, the 1950s.  When the overhead and
stanchions were
replaced in the early '90s (St Marys to Penrith) the extra wire was kept but
attached to
the new stanchions but not in such a way as to be pre-strung for
quadruplication. It more
closely resembles the Loftus Bank feeder.

Chris