Re: home signal

[Railway Rasputin II <bob@fastlink.com.au>]

Hmmm more fairy tails.


> 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. 

Ok how about a Home Signal protects and interlocking or risk area such
as a level xing?


The next 'stop' signal past the home
> signal is known as the 'second home', the next is 'third home' etc etc
> etc. 

And what about a starting signal?? It can be at stop an areas that only
need one home.

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. 

Hmm How about an Outer Home protects the "netural zone" ie sidings,
space for shunting movements to be carried out within the yard limits?


FYI there are a couple of other types of signals such as
> in single lines which are inherently bidirectional, a 'Distant' signal


Distant signals are also used on double lines as well including the main
south.

> 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). 

The landmark signal is in place where all trains must proceed with
caution to the home as opposed to a distant which has two postitions
full clear and caution.
There are 3 types of Landmark signal.
Non reflective with a light, non reflective yellow with cats eyes
reflectorand the retroreflective type that you have mentioned.


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 accept signal is the first controlled signal after an automatic
section. 
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).

Starting signals when cleared allow the train to proceed into the
section provided they have the correct authority/token.
> 
> 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

Source: Safeworking Signalling Manuual and Basic Safe Working Manual.

rgds

rgds