Signal Box Diagrams

[Ken.W]

On 22/08/2019 at 15:43, sem34090 said:

No.6 is to allow a movement from the Up Loop onto the Down Line in order to allow a unit (probably not a loco hauled train, though it could be) to reverse into the Down Loop and thus (if the train had previously been travelling in the up direction from Bogham Road) return from whence it came.

 

Sorry I'm a bit late to this having just seen it

 

If I can deal with the distant signals first.

Remember that when placed below stop signals as here, the distant applies to the signals of the next box ahead, not those of the same box.

Thus, the Down Distant under South's 2 would apply to North boxes's signals and wouldn't be South's distant 1. An Inner Distant for North would also be required under South's 3.

South's Down Distant, 1, which would still be slotted by North, would be a considerable distance off scene from the diagram, as would also be EC's, where also there'd be no distants under any of the stop signals as they're all now worked from the same box.

For the Up Distants, North 10 would be slotted by South, and a South's Inner Distant is required below North 9

How long's the layout? From the look of the track, with platform loops and through main lines, it appears to represent a fairly main line location with a reasonable line speed. So Up Distant EN10/EC25 would be say 3/4 mile on approach to EN9/EC29, ie well off scene.

 

Signal EN3/EC33 appears to be only a short distance beyond the tunnel, so, a Banner Repeater positioned at the tunnel entrance?

 

In the shunt move quoted above, a more prototypical practice, particularly with semaphore signaling would be rather than taking 6 from the Up Loop to shunt wrong direction onto the Down Line, the train would be drawn forward right direction onto the Up Line towards 4, and set back through crossover 8 (which would have a shunt signal for this) into the Down Loop, again in the right direction.

 

[The Stationmaster]

On 01/10/2019 at 23:32, Ken.W said:

 

 

If I can deal with the distant signals first.

Remember that when placed below stop signals as here, the distant applies to the signals of the next box ahead, not those of the same box.

 

Absolutely correct in this case but, of course that was not always the case in the real world although I'm pretty sure the Southern never went in for lower arm inner distant signals applying to stop signals in advance worked from the same signal box.  going way back the GWR did a bit of it.    But the classic example was the former GC mainline in later years when lower arm distants for the Starting Signal(s)were provided below the Home Signal at a number of 'boxes - commonly know as 'hurry up  distants' I believe - their purpose was to give an indication to the Drivers of the 'runner' coal trains that they had now got the road after being checked at the Distant Signal.

[Martin Shaw]

Mike

This was a practice introduced by the LNER, the E&G had a number of boxes with this function, Bo'ness Junction is one that springs to mind and there were no doubt many others. I can't bring to mind any Southern examples either.

Regards

Martin

[RailWest]

There was an example on the S&DJR at Highbridge once where a box had its distant on the same post as its home....but then they always did things differently there :-)

 

The Down Distant at Braunton was rather unusual in that it was not interlocked with its own Down Advanced Starting, on the basis that the latter was slotted by Georgeham Gates as its Down Home with the GG Down Distant being under the Braunton Down Starting.

[micknich2003]

Further to Mike's mention of "Hurry Up Distants, attached the earliest ref I have, Upton H&B Section, LNERly 1931.