On my way to Nevada Bob's today, so was heading across the Dock St level 
crossing (full barrier CCTV) and had a strange show. (all lights are traffic 
lights)

- Amber light shows, yodalarms on, red lights start flashing and nearside 
barriers lower, so far so good. Now wait about 20 seconds for the offside 
barriers to lower, and nothing happens.

- Yodalarms go off, nearside barriers start to rise, when they get to about 
30 degrees from horizontal, yodalarms start again (red lights have been 
flashing throughout) and nearside barriers drop, another twenty seconds (or 
so) pass and offside barriers don't drop.

- Now the red lights go out, yodalarms go off and the near side barriers 
rise to fully vertical, and immediately the whole crossing sequence starts 
afresh (amber lights, yodalarms, flashing red lights, nearside barriers 
down, then offside barriers down, yodalarms off)

- Wait a few minutes and the 170 to Aberdeen comes through and the barriers 
don't rise. No sign of another train for a few minutes and I'm thinking I'll 
just walk round since the crossing is borked. eventually, a DRS 66 (395?) 
trundles up from the tunnel and over the crossing with the ASDA/Malcolm's 
containers in tow, the barriers go up and the lights go out. I'm guessing 
the 66 was sitting in the loop beside platform 4 and allowing the 170 
through.

Now, is this the crossing trying to correct itself because it didn't work, 
or would it have been the signaller trying to cancel the sequence and 
restart it?

And just to satisfy my curiosity, is there a signal in the tunnel between 
platform 4 and the signal on the gantry as you exit the tunnel (heading 
towards Aberdeen from Dundee)? Since I often get off the train at Dundee and 
the signal at the end of the platform is green, which would mean the signal 
on the gantry is at least yellow and the crossing must be closed.

If so, it explains the wait at the crossing as the train has to start from 
the platform and get up the climb to the crossing all while the barriers are 
closed to road traffic.

Thanks for listening to me ramble!

-- 
Doug
"Doug's cool. He's metal ;)" - Fnook
Ignore the old spamtrap work address; mail me on: doug at fruitloaf dot net
http://suicidegirls.com/?hungrydoug

If its a full barrier CCTV crossing, the signaller would be manually
trying to coax the barriers into life by lifting the barriers and
getting them to go down again. No signals can clear until the barriers
are all proved down and the signaller has observed the crossing is
clear on the camera and pressed the Crossing Clear button.

regards
HN28

Doug Farnan wrote:


> And just to satisfy my curiosity, is there a signal in the tunnel between 
> platform 4 and the signal on the gantry as you exit the tunnel (heading 
> towards Aberdeen from Dundee)? Since I often get off the train at Dundee and 
> the signal at the end of the platform is green, which would mean the signal 
> on the gantry is at least yellow and the crossing must be closed.


So far as I recall, no. Admittedly, that's from when I worked on the 
commissioning of the new signalling in 1985!

wrote in message 
news:1122755253.625392.222460@f14g2000cwb.googlegroups.com...

> If its a full barrier CCTV crossing, the signaller would be manually
> trying to coax the barriers into life by lifting the barriers and
> getting them to go down again. No signals can clear until the barriers
> are all proved down and the signaller has observed the crossing is
> clear on the camera and pressed the Crossing Clear button.
>
> regards
> HN28
>


It is a full barrier CCTV crossing.

Thanks for that, I didn't know if it was the barrier controls doing it or 
the signaller raising and lowering the barriers. I guess the signal at the 
end of the platform would have been held at red (or yellow since there is 
another before the crossing) until it was sorted out?

-- 
Doug
"Doug's cool. He's metal ;)" - Fnook
Ignore the old spamtrap work address; mail me on: doug at fruitloaf dot net
http://suicidegirls.com/?hungrydoug