Signalling question.

[The Stationmaster]

1 hour ago, simon b said:

I had another look around and I think I've found a similar prototype for the track layout at Banbury station. 

 

The down platform relief line had what appears to be an un-signaled trailing connection to a pair of sidings about half way along it's length, there was a 3 lever ground frame provided even though the signal box is only at the platform end. Am I correct in thinking thinking this would be worked in the same way 5BarVT describes a few post's ago?   https://www.roscalen.com/signals/Banbury/South.htm

Lattetday alteration - the GF is an LNWR pattern frame w so was installed when the area had gone under LMR control.

 

The connections were originally worked by Banbury South and signalled in the appropriate manner - ground discs etc..

[Grovenor]

11 hours ago, simon b said:

Just so I understand things fully a train cannot arrive directly into the siding as the ground frame must be locked to clear the signal into the platform, but a train can depart from the siding directly as the platform starter is not interlocked with the groundframe.

Exactly, for the inbound move with the loco pushing the consist should stop just before the points then the signaller replace the entry signal and release the ground frame to the shunter

[Michael Hodgson]

1 hour ago, Jeremy Cumberland said:

 

Lever 1 is half blue, implying an FPL, but I can't see one, and it's not on the lead. Perhaps blue has another meaning I am not aware of.

 

 

All blue is used for a FPL, also a clearance bar (if you can find any these days)

 

Blue over black is used where one lever combines the function of throwing the point and locking it - this woud be a power-worked point (point motors have point locking built-in) or an "economic FPL" (common MR mechanical practice, not much used elsewhere)

 

Blue over brown is the standard colour for a Release, a Bolt locking lever, a Direction lever or an Annets Key lever.

On the Banbury GF photo I can actually read the lever plate - it says "Release"

Lever 2 reads Down Relief Down Siding

As Jeremy says, there's no need for an FPL as it's only a trailijng connection on a Down Line.

The SB Diagram has a note that (GF)1 released by 10 lever in the box.

The horizontal bars secured to levers lock them such that you can't pull 3 without first pulling 2, which you can't pull until you pulled 1, although this is not shown on the lever pull plates.

[simon b]

2 hours ago, Michael Hodgson said:

 

All blue is used for a FPL, also a clearance bar (if you can find any these days)

 

Blue over black is used where one lever combines the function of throwing the point and locking it - this woud be a power-worked point (point motors have point locking built-in) or an "economic FPL" (common MR mechanical practice, not much used elsewhere)

 

Blue over brown is the standard colour for a Release, a Bolt locking lever, a Direction lever or an Annets Key lever.

On the Banbury GF photo I can actually read the lever plate - it says "Release"

Lever 2 reads Down Relief Down Siding

As Jeremy says, there's no need for an FPL as it's only a trailijng connection on a Down Line.

The SB Diagram has a note that (GF)1 released by 10 lever in the box.

The horizontal bars secured to levers lock them such that you can't pull 3 without first pulling 2, which you can't pull until you pulled 1, although this is not shown on the lever pull plates.

 

So for a ground frame on the SR, am I correct in thinking I need two blue levers and one black?

 

Lever 1 blue over brown - Release

Lever 2 blue - Facing point lock

Lever 3 black - Throw point

Edited April 20 by simon b
Wrong color!

[The Stationmaster]

23 hours ago, simon b said:

 

So for a ground frame on the SR, am I correct in thinking I need two blue levers and one black?

 

Lever 1 blue over brown - Release

Lever 2 blue - Facing point lock

Lever 3 black - Throw point

Not necessarily as it depends on how it was released.  Many ground frames did not havea release lever but were unlocked by an Annett's Key so only - at a facing connection - needed a blue lever and a black lever.  A lot depends on Company/Reh gional practice and the type opf equipment in use.

[Nick C]

On 20/04/2024 at 11:30, Grovenor said:

Exactly, for the inbound move with the loco pushing the consist should stop just before the points then the signaller replace the entry signal and release the ground frame to the shunter

This might be a "depends on the company" one, but I'd have thought it could be locked such that a shunt signal could be cleared into the platform - that only allows the driver to proceed as far as the line is clear, which would be to the toe of the points.