'Cattle grid' in the 4ft?

[rockford]

Probably quite a basic question, but what are the small (12" x 24") grids for in the middle of the track?
They look like small cattle grids and the rails run parallel to the track.
Can't really describe them any better than that unfortunately. They don't seem to be protecting anything underneath and their locations don't correspond to any other equipment.
Thanks.

 

[Hydro]

Sounds like TPWS antennae. They are small antennae that act as transmitters and receivers for the Train Protection and Warning System. You'll find them on the approach to signals , some speed restrictions, and junctions, and at some (most now?) signals. They can stop a train if the train is approaching too fast to a red aspect, or if a train passes a red aspect.

 

[A-driver]

They arent TPWS grids are they? Are they located on the approach to signals, PSR's or buffer stops? Or if on the south central region they may be PIBs (platform information beacons) which are to give the train instructions on SDO.

 

[rockford]

Sounds like TPWS antennae. They are small antennae that act as transmitters and receivers for the Train Protection and Warning System. You'll find them on the approach to signals and junctions, and at some (most now?) signals. They can stop a train if the train is approaching too fast to a red aspect, or if a train passes a red aspect.

That would make sense.
Are those different to the large yellow railway sleeper-sized 'things' which I always understood were for AWS? (sorry, don't know correct term).
Thanks for the response.

 

[A-driver]

Beat me to it by a second or so! There are normally 2 (an arming loop and a trigger loop) on approach to speeds, signals and buffer stops and the speed is defined by the distance apart they are. Once you pass the arming loop you must not hit the trigger within a second or the emergency brake comes on and you are taken off track for many, many weeks whilst they tell you what a naughty boy you have been!

 

[Hydro]

Yes, they are AWS (automatic warning system) magnets, which give indications to a driver as to the aspect of the signal that he must acknowledge else the brakes apply. That system is there for the driver to show he is reading and understanding the signals, and to bring the train to a halt if the driver is unable to acknowledge restrictive aspects. You can also find them warning drivers of upcoming speed restrictions.

TPWS is an extra layer of protection over the top of AWS to prevent Signals Passed At Danger (SPAD's).

 

[rockford]

Yes, they are AWS (automatic warning system) magnets, which give indications to a driver as to the aspect of the signal that he must acknowledge else the brakes apply. That system is there for the driver to show he is reading and understanding the signals, and to bring the train to a halt if the driver is unable to acknowledge restrictive aspects. You can also find them warning drivers of upcoming speed restrictions.

TPWS is an extra layer of protection over the top of AWS to prevent Signals Passed At Danger (SPAD's).

Excellent. Thanks for the comprehensive reply one and all.

 

[The Snap]

TPWS is an extra layer of protection over the top of AWS to prevent Signals Passed At Danger (SPAD's).

Which I believe came into mainstream use after Ladbroke Grove?

 

[GB]

Beat me to it by a second or so! There are normally 2 (an arming loop and a trigger loop) on approach to speeds, signals and buffer stops and the speed is defined by the distance apart they are. Once you pass the arming loop you must not hit the trigger within a second or the emergency brake comes on and you are taken off track for many, many weeks whilst they tell you what a naughty boy you have been!

Don't know who you work for or if your post was said in jest or not, but its not common practice (not round here anyway) to be taken off after a TPWS overspeed activation let alone taken off for weeks.

 

[pendolino]

TPWS is an extra layer of protection over the top of AWS to prevent Signals Passed At Danger (SPAD's).

I know I might be being a bit pedantic, but TPWS generally doesn't prevent a SPAD, but it does mitigate the effects. If the TSS (at the signal at danger) or OSS (on the approach to a red) activates the TPWS resulting in an Emergency Brake Application, the train is still likely to pass the signal, but hopefully will be brought to a stand before proceeding far enough to cause a collision.

Don't know who you work for or if your post was said in jest or not, but its not common practice (not round here anyway) to be taken off after a TPWS overspeed activation let alone taken off for weeks.

Southern drivers having a TPWS OSS activation are taken off track; the length of time varies, some have been off for weeks but that tends to be where there is a history of incidents. I realise other TOCs/FOCs do things differently.

 

[causton]

I was in the first coach of a Gatwick Express train today from Brighton-Victoria and I heard the sounds of the safety systems from the cab that play to the driver. I know there was the two tones based on what the signal was, but there was also a constant beeping which would go on for a couple of seconds then stop, and then the 'ding' for the signal would come. Was this vigilance or something else?

 

[GB]

Was this vigilance or something else?

Certainly sounds like it.

 

[A-driver]

I am with southern and we are off track for TPWS. Even 1mph above trigger speed approaching a PSR where the download shows you would have been way under speed by the board can mean off track for 6 weeks or so!

 

[GB]

Man that sounds harsh! At my place if you have a TPWS OSS activation, its talk to the signaller, reset and off you go with a quick chat to your manager to explain things the next time you book on. I have not known anyone to be taken off purely for an OSS activation not least for weeks!

 

[LE Greys]

Would you ever see a real cattle grid in other countries. I know that all lines in Britain have to be fenced to prevent animals straying into the path of trains. Still, there are other countries with unfenced lines, and accommodation crossings back home, so any genuine cattle grids?

 

[OxtedL]

In the middle of the tracks would be an unfortunate place to have a cattle grid...

This clip here is heart breaking... http://www.youtube.com/watch?v=nieK4GHov-Y

 

[lewisf]

Would you ever see a real cattle grid in other countries. I know that all lines in Britain have to be fenced to prevent animals straying into the path of trains. Still, there are other countries with unfenced lines, and accommodation crossings back home, so any genuine cattle grids?

What about here?

 

[LE Greys]

What about here?

I forgot about those.
--- old post above --- --- new post below ---

In the middle of the tracks would be an unfortunate place to have a cattle grid...

This clip here is heart breaking... http://www.youtube.com/watch?v=nieK4GHov-Y

That's horrible. Looks like the cowcatcher didn't work.

 

[GearJammer]

That's horrible. Looks like the cowcatcher didn't work.

Its not a cow catcher.... its a snow plough!
--- old post above --- --- new post below ---

This clip here is heart breaking... http://www.youtube.com/watch?v=nieK4GHov-Y

I don't think it was just his heart that got broke.... but probably every bone in its body, had to laugh at the ground beef comment under the clip, lol

 

[Crossover]

I was in the first coach of a Gatwick Express train today from Brighton-Victoria and I heard the sounds of the safety systems from the cab that play to the driver. I know there was the two tones based on what the signal was, but there was also a constant beeping which would go on for a couple of seconds then stop, and then the 'ding' for the signal would come. Was this vigilance or something else?

As someone else mentioned, it sounds vigilence. I think this is activated after 60 seconds when the train is not in neutral and the main controls (power or brake) haven't been moved for 60 seconds. Even with the train stopped and the DRA active I think the vigilence will still go. No response means application of emergency brakes.

What about here?

They have those in quite a few places - I think its equally a deterrent to keep people off the line as well as animals - they have them on quite a few platform ramps as well