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ABCLs operating in degraded mode

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ABCLs operating in degraded mode

Unread postby Suffolk Lad » Mon Jun 6, 2016 9:13 am

Hi All,

I have a fairly specific question which I am hoping that someone on here may be able so answer.

As far as I am aware, ABCLs are provided with driver's plungers in case the crossing fails to activate. Also, I am aware of some ABCLs where a running signal is located inside the strike-in point so that the DCI is positioned on the same post, e.g. Minehead (but maybe some on the mainline network also?).

If the running signal cannot be cleared for whatever reason:

(a) What is the procedure for the driver operating the driver's plunger?
(b) If the driver's plunger is operated, does this still call the crossing? If so, what signal is displayed to the driver?

Any feedback would be most welcome.

Many thanks.

SL
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Re: ABCLs operating in degraded mode

Unread postby Stuart Johnson » Mon Jun 6, 2016 11:17 am

The drivers instructions for ABCLs are in rule book module TW8 section 4:

http://www.rssb.co.uk/rgs/rulebooks/GER ... ss%207.pdf
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Re: ABCLs operating in degraded mode

Unread postby Suffolk Lad » Mon Jun 6, 2016 12:28 pm

Stuart Johnson wrote:The drivers instructions for ABCLs are in rule book module TW8 section 4:

http://www.rssb.co.uk/rgs/rulebooks/GER ... ss%207.pdf


Many thanks.

That implies that a DCI provided on the same post as a running signal will never have an emergency plunger. Please correct me if I am wrong.
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Re: ABCLs operating in degraded mode

Unread postby Mark Lamb » Mon Jun 6, 2016 6:31 pm

If I remember correctly, Hunmanby Station ABCL, for movements on the single-line towards Bridlington, doesn't have a DCI. Instead it has a two-aspect c/l section signal that incorporates the function of the DCI. In other words, the signal will only clear after the route has been set, the conditions in the route have been met, the ABCL has been called and barriers proved down, etc., for 30 seconds. If there is a failure of the route, but not the level crossing, then an emergency plunger is available for use under the instruction of the signaller, who (I assume) can authorise its use and permission to pass the signal at danger.

So there's one instance of an emergency plunger associated with a signal, but I would guess they're as rare as hen's teeth, as my old supervisor used to say!
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Re: ABCLs operating in degraded mode

Unread postby Mike Hodgson » Mon Jun 6, 2016 8:28 pm

Surely you should be overriding the crossing but still need the route, especially as it's onto a single line?
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Re: ABCLs operating in degraded mode

Unread postby JRB » Mon Jun 6, 2016 8:50 pm

Instructions from the signal box override anything.
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Re: ABCLs operating in degraded mode

Unread postby Suffolk Lad » Mon Jun 6, 2016 9:11 pm

That is interesting re. Hunmanby, thanks. So, when a driver uses the emergency plunger, he has no indication that the crossing is operating correctly (i.e. road lights flashing)?
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Re: ABCLs operating in degraded mode

Unread postby Mark Lamb » Tue Jun 7, 2016 10:15 am

Mike - the crossing is inhibited unless the route has been set, therefore the emergency plunger is to activate the crossing only. Permission to proceed is given by the signaller / pilotperson. Perhaps I would have been better to say 'failure to obtain proceed aspect', rather than 'failure of the route'.

SL - there is, again if I remember correctly, a miniature Driver's White Light (rather than DCI, as there is no red light associated with it). On the cabinet that contains the emergency plunger, and the SPT - or perhaps the SPT is close to it - there is an externally mounted miniature DWL. This operates exactly as if it were a full size one, with the same conditions needing to be met, but only illuminates in conjunction with the emergency plunger.

Regards,

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Re: ABCLs operating in degraded mode

Unread postby Suffolk Lad » Tue Jun 7, 2016 10:42 am

Many thanks Mark. That is great, and just what I was looking for.

I found a picture of it on the web:

http://www.oldwaitingrooms.co.uk/images/home1.jpg
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