Re: Level Crossing (Vic)

["Notagunzel" <notagunzel@bigfoot.com>]

Christopher_Martin GORDON <cmgord@ecr.mu.oz.au> wrote in
message 7o2s86$b0t$1@mulga.cs.mu.OZ.AU">news:7o2s86$b0t$1@mulga.cs.mu.OZ.AU...

> I think he is talking about signal L665 which is controled
by lever 2 at
> Mitcham, the lever would have been at Normal while the
train in the siding
> was shunted out and to Ringwood.  Once lever 2 was put
back to reverse then
> the crossing should have started and the signal cleared
once the boom gates
> were horozintal.  I can't explain why the signal was at
proceed with out the
> crossing operating, the only time this signal should be at
proceed without
> the corssing operating is when express selection is made
at Blackburn
> (either by pushing the express button when switched in, or
by the train
> not stopping at Blackburn when switched out).

Methinks that the Express Stopping control on that
particular auto is slightly different, in that the auto
clears for a stopper when the train arrives in Nunawading
platform, but the approach section (not the holding section)
for Rooks Rd commences just off the end of the platform.

> If you are all confused with the layout/operation of
Mitcham have a look
> at my web page.

I already have, all very good :o)

> http://www.ecr.mu.oz.au/~cmgord/trains/signalling/mitcham/

> : > Whilst on the RTA's L class / Hitachi tour yesterday,
we were heading out
> : > to Belgrave when we were stopped at Rooks Rd level
Crossing, Mitcham.
> : > (Singal is about 20 metres from crossing)  There was a
spark in the siding
> : > at Mitcham, which was to form a Ringwood to Belgrave
shuttle before us.
> : >
> : > After the spark departed the tour train was able to
proceed, but the level
> : > crossing booms were not down.  Having the stick but no
booms, the train
> : > crawled at no more than 3 kmh, when the booms finally
decided to operate.
> : > The train reached the roadway just the booms finished
lowering.

Taken at face value, a Wrong Side Fault.  This is somewhat
serious.  It suggests that there is an undiscovered design
fault (bit hard to believe, the installation was done ages
ago, any fault should have come to light by now, or could
possibly be a defective relay.  There is a known problem,
that if a signal relay is energised permanently, without
dropping or picking, for months (years?) on end, that it can
freeze in the picked position.

But this is all purely speculation.

> : > What's going on here?
> : > Is this the same problem/situation as at Dandenong a
while back (discussed
> : > thoroughly on Aus.Rail)?

AFAIK the definitive answer to the 'incident' at Dandenong
never came to light yet.

--
Mr Notagunzel.
Rail Transportation Connoisseur.
notagunzel@bigfoot.com
(Waiting for the next move at
http://www.bigfoot.com/~notagunzel)