Re: home signal

[signal_spotter@my-deja.com]

In article <390fba62$0$31504@news01.syd.optusnet.com.au>,
  "Tom" <hammerheads@optusnet.com.au> wrote:
> hi there again
> im still just learning some things.
>
> ok how does a home signal operate?
> tom
>
>

Tom,

A 'Home' signal is the first signal reached by a driver on approaching
an interlocking area, and which actually affords the protection for the
junction, crossing, or other risk. The next 'stop' signal past the home
signal is known as the 'second home', the next is 'third home' etc etc
etc. If the need arises (such as if there was a ground frame just
before the Home), an 'Outer Home' signal is placed before the 'Home' to
protect that. FYI there are a couple of other types of signals such as
in single lines which are inherently bidirectional, a 'Distant' signal
which is placed at braking distance in rear of the home and gives the
driver advanced warning of the state of the home. In little used lines
the 'distant' is replaced by a 'landmark' (a retro-reflective yellow
triangle). In Automatic signalled areas (unidirectional lines) the last
signal approaching the 'home' is called the 'Accept' and it too is
placed at braking distance to the home. The signals reading from an
interlocking into a single line (bidirectional line) are
called 'Starting' signals and they give the driver authority to proceed
into the block (providing there are no other safeworking procedures to
adhere to such as train staff).

Anyway I hope this explains it. As to 'what operates a home signal',
well a lever or push button does. But I guess you're not really after
that type of answer :-)

cheers

Ian Hayes
Railway Signal Design Engineer


Sent via Deja.com http://www.deja.com/
Before you buy.