Re: Ringwood

[cmgord@ecr.mu.oz.au (Christopher_Martin GORDON)]

: > I won't go through the moves you can now do, that a frame
: would never let
: > you do.  Like getting the signal 302 to procees, then run
: points 204 (just
: > after 304)  There are no speed trips, and no overlap past
: 304.  You
: > could never do that with the frame.

: So if I could please clarify, with the frame 302 locked 204
: both ways, but with the panel you can 'swing' 302's overlap
: with 204?  I assume 204 is only free in these circumstances
: when the alterative route is also free?


Look at http://cmgord.alphalink.com.au/trains/ringwood/rwd_dia3.jpg

If you cleared signal 2 for a move into No.3 it would lock points:
17,18,35,24,25,49,50.  It is the locking of 49,50 because of no
overlap.  So say a Belgrave train came in, the points would be approch
locked for about 120 seconds.  Then (provided lever 2 was restored) you
could reverse 51,50,49,46 then signal 3 (usually 63 was reverse, unless
shunting)

With the panel you can clear signal 302 (was 2) and the line is set
up to 304 (was 3) there are no speed trips in the down direction, so 
a Train could get to 304 at speed and pass it.  With the points 204 (was
49,50) free to move. (But is the track is down ie train there, then the 
points will lock)

The panel now is: (FSS to LIL via 3) 302,225,204,304,328
The frame would be (using same numbers) 204,302,225,304,328

Basically, you can run points 204 with no overlap protection.
(there is about 2-3 sleepers between signal 304 and points 204,
not like about 30 metres between signal 302 and points 202)

If there were speed trips for the down direction on the down platform
then it would be better.  (speed trips for up direction, and both
directions on the middle platform)
--
Chris Gordon
http://www.ecr.mu.oz.au/~cmgord