Re: Derailment at Concort West - Reason

[Tony Gatt <kevchris@cybertune.com.au>]

McFergus@my-dejanews.com wrote:

> Let me change the conversation to NSW signals. If I trip up somewhere, someone
> please let me know!
>
> The normal sequence that a driver sees for an advance signal at danger
> assuming double light four aspect signalling is as follows:
>
> G            G            G            R
> G   ----->   Y   ----->   R   ----->   R
>
> And the sequence for a turnout (assuming that the line ahead through the
> turnout is clear) is:
>
> G            G            Y  [tn'out]  G
> G   ----->   Y   ----->   Y   ----->   G
>

I am confused by this method of Signalling in this Instance.
Several people have commented that the train at Concord was being put into a
"siding" for track circuit cleaning purposes. This is understandable. In
Melbourne, I believe if a track circuited rail is not used for 72 hrs, then it is
booked out of service and must be inspected and tested by the fitters.

Could someone please explain what form of signalling controls the entrance to this
rarely used "Holding Loop".

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"Indecision is the key to flexibility"

Tony Gatt.
Mailto:tony_g_1@hotmail.com

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