How are level crossings signalled in 2022? Should a Green aspect show when the main road is still open?

[The Stationmaster]

4 hours ago, RailWest said:

As a level-crossing with its gates across the rails was not normally regarded as an obstruction of the Clearing Point, then IMHO a Warning Acceptance would neither be necessary nor appropriate as de facto the CP was not fouled and so normal Reg 4 acceptance would be feasible (assuming all other requirements had been satisfied).

 

Of more importance was the fact that normally not only would the stop signal immediately in rear of the gates require the gates to be locked across the road before it could be cleared, but also the next stop in rear worked from the same box also have the same requirement. Sometimes the latter had a subsidiary arm which could be lowered to permit a train to enter a platform without the need to close the gates, in some cases the locking simply did not exist anyway.

 

If you go to Blue Anchor station you will often see instances where, if a Down train arrives early and/or the Up train is late, then the gates are closed against the road, the Down Inner Home (3) is held 'on', the Down train rolls into the the platform and stops, whereupon the gates are opened to road traffic again. This apparent 'unnecessary' closing of the gates puzzles/annoys some car drivers who are not aware that, out of sight around the corner towards Taunton, is the Down Home (2) which can not be cleared to admit a train into the platform unless the gates are shut.

But as the GWR normally 'locked (stop signals) two back' did they extend that principle to level crossing gates while other companies/BR Regions didn't necessarily do the same?   In very many cases - in fact probably the majority - level crossings were only protected by a single stop signal which might only be a few feet in rear of the crossing stop signal.    And of course on secondary lines level crossings worked by a Crossing Keepr might not havea ny separate protecting semaphore signals at all. 

 

And as the level crossing was not taken into account in the Clearing Point a train could be accepted under a full Line Clear towards that signal which could be at danger with the crossing gates open to road traffic.

[RailWest]

6 minutes ago, The Stationmaster said:

.......  In very many cases - in fact probably the majority - level crossings were only protected by a single stop signal which might only be a few feet in rear of the crossing stop signal.    And of course on secondary lines level crossings worked by a Crossing Keepr might not havea ny separate protecting semaphore signals at all. 

 

And as the level crossing was not taken into account in the Clearing Point a train could be accepted under a full Line Clear towards that signal which could be at danger with the crossing gates open to road traffic.

>>>......  In very many cases - in fact probably the majority - level crossings were only protected by a single stop signal which might only be a few feet in rear of the crossing stop signal....

 

From what I can recall, most examples that I have seen of L&SWR/SR locking tables for such locations had the 'lock 2 back' applied.

 

>>>....on secondary lines level crossings worked by a Crossing Keeper might not have any separate protecting semaphore signals at all...

Indeed. Most odd in my mind, given that trains running at 'fast' speeds might pass thru' other crossings just a few miles away which had Distant and Home signals. Even more odd IMHO when the latter was found on single-track 'minor branch lines' yet the former persisted on double-track 'main lines'

 

[phil-b259]

On 12/08/2022 at 21:15, SM42 said:

 

That requires the automatic crossing to be controlled in some way and as such if one forgot to operate the stopping sequence, would the crossing time out and show up as failed?  

 

 

It would - however the key thing is the barriers would be down and road users therefore protected (assuming they don't zig-zag round them). When the train has passed over the crossing the correct operation of the final treadle will cause the crossing to rise and no longer show 'failed'

 

(When a crossing is indicated as 'failed' then the signaller can tell drivers they may proceed over it as long as they stop on the approach and satisfy themselves the road lights are flashing and the barriers are down)

[phil-b259]

13 hours ago, Pandora said:

Operationally needs to be a Controlled Signal,  the signaller replaces the controlled signal to red  when a train is to held or delayed at the platform,  with the train safely at a stand behind the red, the signaller can open the crossing to road traffic, otherwise long unnecessary delays and traffic jams for motorists

 

The crossing is an AHB - the signaller has NO INVOLVEMENT in the crossing operation.

 

What the signaller does have is the ability to re-place the signals either side of said crossing to red should a person phone up with a long / slow vehicle / animals / etc and the signaller needs to prevent trains passing over the crossing. As such the aforementioned signals may be replaced to danger they must be plated as 'controlled' signals - because they are exactly that.

 

The other thing the signaller may have is a 'stopping' / 'non stopping' selection - this will alter the stage at which the crossing gets triggered and will also have some interaction with signals so that if 'stopping' is accidentally selected then a 'non stopping' train gets slowed down and is forced to behave like a stopping train thus preserving crossing timings.

 

Note the RULES for AHB crossings MANDATE:-

 

(i) No more than 3 tracks

 

(ii) 85% of trains arriving at the crossing MUST pass over it within 36 seconds of the sequence starting. If the 85% figure cannot be met then the line speed must be reduced till it is or selective controls (e.g. stopping / non stopping) be employed. If the latter are fitted then it must be impossible for an accidental selection to result in trains arriving at the crossing without it having been triggered and be in a safe condition for road users.

 

(iii) The signals either side MUST be able to be replaced to danger by the signaller.

 

(iV) The supervising signaller MUST have a 'barrier failed, 'barriers up' and 'power failure' indications for (plus telephone communication with) said crossing

 

Edited August 14, 2022 by phil-b259

[Neal Ball]

Thanks guys.

 

We had an interesting conversation at Didcot today about this. I now understand that the crossing is treadle operated - further up the line, possibly where the emus whistle.

 

Thanks to the Mikes @The Stationmaster & @Mike_Walker for going through it again. The latter Mike spoke about in respect of 3 crossings on the Swindon panel. (Well worth a look).

[phil-b259]

15 minutes ago, Neal Ball said:

Thanks guys.

 

We had an interesting conversation at Didcot today about this. I now understand that the crossing is treadle operated - further up the line, possibly where the emus whistle.

 

Thanks to the Mikes @The Stationmaster & @Mike_Walker for going through it again. The latter Mike spoke about in respect of 3 crossings on the Swindon panel. (Well worth a look).

 

It may be 'treadle operated' but different treadles come into play for 'stopping' and 'non stopping' trains plus there will be a set of 'run by' treadles in case a train SPADs the signal.

 

The controlling circuitry can get pretty complicated and very different from a bog standard AHB where 85% of trains will all be travelling at full linespeed