FPLs for crossovers - are they always present, and how are they shown?

[Annetts key]

So, to clarify, before the standard changed (under BR sometime between 1988 and 1994 I think, but I can’t remember the actual year), FPL (facing point lock) equipment was only required for points that were facing for booked passenger train movements (as in trains actually advertised as passenger trains for passenger use).

All other points did not require FPL equipment. However, some point operating equipment (POE) (such as clamp locks - RCPL rail clamp point lock, have FPL equivalent equipment as standard).

So for points that were used in the facing direction, that were not FPL fitted, light locos, freight trains, engineering trains, inspection trains and empty passenger trains running as ECS (empty coaching stock), as well as on track machines could all use these points.

If an in service passenger train had to use points not provided with a FPL, then as described above, they would have to be fitted with a clip and a scotch. The same applies if a FPL or the POE has failed and detection cannot be given.

Why was this done? Because it was cheaper. Less equipment, less complexity equals less cost.

Since then, things have changed. Firstly there are less staff available to carry out point clipping and scotching, secondly the relative cost has changed (the cost of providing a FPL with current POE is insignificant as all modern power operated POE comes with a FPL as standard) and it’s operationally more flexible to have all points on main running lines provided with FPLs.

Different railway companies used different symbols on their various diagrams, some BR regions continued their own thing. For Western, normally on S&T diagrams (not signallers) an FPL is shown as below:


For signal box diagrams, either “FPL” and then the lever number was put on the diagram, or just the lever number for the FPL.

 

[Railsigns]

It may be worth mentioning that the FPL shown in the previous post is drawn in a non-preferred way. For the points depicted in that example, the FPL symbol would normally be flipped horizontally so that the cross is below the track.

 

[Annetts key]

It may be worth mentioning that the FPL shown in the previous post is drawn in a non-preferred way. For the points depicted in that example, the FPL symbol would normally be flipped horizontally so that the cross is below the track.

Sorry, it was the first one I found! I did think it looked slightly different.

 

[Saj8]

I drive this route, and this question piqued my interest, so I had a look at our route maps to see what they showed.

This is the map of Henwick, which shows FPLs in all the right places, which interestingly shows 12A, 10A and 10B points as being fitted with an FPL, so presumably a train can use the turnback with passengers on? I did not know that.


Then here is Newland East, with no points locks shown, as expected. I vaguely remember using the crossover in 2016 as described in post #29, with the pilotman verifying with the signaller at Great Malvern that the points had been clipped and scotched before authority was given to proceed back towards Worcester. I haven't used them since.


Then at Malvern Wells, our map shows a points lock fitted to #6 points on the single line, again as expected.


But according to our map, there is no points lock fitted to #31B points, that would send a train into the loop, which I would expect to be there. Could that be an error on the map, or is there really no FPL fitted there?

 

[Gloster]

I would think that there must be a FPL on 31B as it is facing to passenger trains heading for Ledbury and Hereford. It is either a mistake or the diagrams do not show motor points that have an FPL as part of the unit, rather than on a separate lever. A look at a picture of the interior of the box suggests that it is a motor point with FPL as the lever is half blue and half black.

 

[zwk500]

I drive this route, and this question piqued my interest, so I had a look at our route maps to see what they showed.

This is the map of Henwick, which shows FPLs in all the right places, which interestingly shows 12A, 10A and 10B points as being fitted with an FPL, so presumably a train can use the turnback with passengers on? I did not know that.

I believe the turnback is utilised by Charter services turning round the triangle at Worcester.

Then here is Newland East, with no points locks shown, as expected. I vaguely remember using the crossover in 2016 as described in post #29, with the pilotman verifying with the signaller at Great Malvern that the points had been clipped and scotched before authority was given to proceed back towards Worcester. I haven't used them since.

Wasn't there a recent thread on this box?

But according to our map, there is no points lock fitted to #31B points, that would send a train into the loop, which I would expect to be there. Could that be an error on the map, or is there really no FPL fitted there?

I agree with @Gloster, this looks like an omission due to motor worked/same lever locked points. 31B would certainly need an FPL.

 

[MarkyT]

This is the map of Henwick, which shows FPLs in all the right places, which interestingly shows 12A, 10A and 10B points as being fitted with an FPL, so presumably a train can use the turnback with passengers on? I did not know that.
View attachment 118500

This facility was upgraded quite recently so might have adopted the modern standard of fpls for all affected moves. I think there's a typo on 10A points in that the fpl shows no number. Reckon it might be 7A.

But according to our map, there is no points lock fitted to #31B points, that would send a train into the loop, which I would expect to be there. Could that be an error on the map, or is there really no FPL fitted there?
View attachment 118503

Odds are it's an electric point mechanism with a built in fpl or equivalent operated by the same lever as suggested above.

 

[Efini92]

I would think that there must be a FPL on 31B as it is facing to passenger trains heading for Ledbury and Hereford. It is either a mistake or the diagrams do not show motor points that have an FPL as part of the unit, rather than on a separate lever. A look at a picture of the interior of the box suggests that it is a motor point with FPL as the lever is half blue and half black.

Does it need FPL if there’s detection on the points?

 

[Gloster]

Does it need FPL if there’s detection on the points?

Most definitely it does: detection is not in itself proof that the point is fully and safely over.

EDIT: I could also add that the FPL is fully interlocked with other points and signals.

 

[Efini92]

Most definitely it does: detection is not in itself proof that the point is fully and safely over.

Ah I guess it’s not because of that then. Cheers.

 

[Railsigns]

Most definitely it does: detection is not in itself proof that the point is fully and safely over.

Detection of the points is proof that they are fully and safely over. The purpose of the FPL is to physically hold them in that position, which detection alone cannot do.

The FPL is also detected, to prove that the lock is engaged.

 

[Annetts key]

If a point has detection, but no FPL, it’s only the point operating mechanism that holds the switch rails in the correct position. Detection if provided, is tested with a 5mm gauge, if the closed switch rail is open 5mm or more, detection should not be given.

The purpose of an FPL is to prevent signals from being cleared if the FPL cannot be engaged (“bolted”) (complete it’s travel if a mechanical lever), hence proving that the closed switch rail is indeed closed. And to hold the switch rails in place independently of the point operating mechanism. Thus ensuring that the closed switch rail cannot move open under or with the passage of a train. Hence the word ‘lock’, because the point is locked in position.

For mechanical points and traditional point machines, the FPL includes it’s own independent point stretcher which is fitted in addition to the normal P.Way point stretchers.

A FPL must not be able to engage (“bolt”) if the closed switch rail is open by 3.5mm or more (we use a 3.5mm gauge).

Where a FPL is fitted, detection is only given if the closed switch rail is detected and the FPL is engaged (“bolted”).

All new power operated points have both detection and a FPL (or equivalent).

The provision of FPLs has significantly increased the safety of the railways.

It’s the job of the interlocking (be it mechanical, electrical or computerised) to confirm that a point has been commanded to the correct position and is detected in the correct position.

 

[MarkyT]

Note FPLs for facing passenger movements were a Board of Trade requirement for new railways from the late 19th century. 'The First Requirements of the Inspecting Officers of Railways' in 1858 forbade facing points except on single lines and at double junctions, but by 1892 other facing points were allowed, albeit still discouraged, but had to be equipped with an FPL and locking bar mechanism.

The following document shows an 1892 copy with changes annotated for the 1902 edition.

Requirements, &c. of the Board of Trade in Regard to The Opening of Railways :: The Railways Archive

Archive of UK railways documents

www.railwaysarchive.co.uk

Edit: date of First Requirements corrected

 

[Annetts key]

Note FPLs for facing passenger movements were a Board of Trade requirement for new railways from the late 19th century. 'The First Requirements of the Inspecting Officers of Railways' in 1958 forbade facing points except on single lines and at double junctions, but by 1892 other facing points were allowed, albeit still discouraged, but had to be equipped with an FPL and locking bar mechanism.

The following document shows an 1892 copy with changes annotated for the 1902 edition.

Requirements, &c. of the Board of Trade in Regard to The Opening of Railways :: The Railways Archive

Archive of UK railways documents

www.railwaysarchive.co.uk

Is one of the above dates a typo?

 

[MarkyT]

Is one of the above dates a typo?

Indeed! lying in bed with COVID trying to type! It is of course 'The First Requirements of the Inspecting Officers of Railways' in 1858. I'll edit my previous post.

 

[Annetts key]

Thanks, I hope you quickly recover from COVID19. I know from experience that it’s not nice.

Do you happen to know when regular testing of FPLs became a requirement?

 

[MarkyT]

Thanks, I hope you quickly recover from COVID19. I know from experience that it’s not nice.

Cheers!

Do you happen to know when regular testing of FPLs became a requirement?

I don't I'm afraid. Maybe a recommendation after a particular accident?