Great Western Coffee Shop

Was at Taplow station last night helping the "Community Safety Officer" give out electric timeswirtches to arrivng commuters.

At about 18:45 a very sick HST came through on the Down Main obviously running on one powercar. I understand it expired completely at Didcot.

The interesting thing to observe was the subsequent delays to following trains and the effect ATP has on locking down train speed.  Each of the subsequent trains were very slow approaching Taplow as they had been locked down for a double  or single yellow and although the driver coming through the platform can see the signal had changed up he cannot accelerate as we don't have a signal wire back from the signal and you can't accelerate until you hit the ATP grid at the signal. Whereas without ATP the driver could have started to accelerate on sighting the higher aspect.

DB LZB high speed signalling system has continuous arials so the train is always running at optimum speed and accelerates and decelerates according to the signal received and not just the aspect of the conventional signals. Thus it alows suitably equiped trains to run faster on exisitng lines which have both LZB and conventional signalling rather than just the high speed lines for which it was designed.

 

the signal at Taplow has an infil grid mid section however it is only about 400 yards before so therfore when it has updated to a single yellow from a red a driver may only travel at that signals release speed which if memory serves me correct in this case is 25mph until his/her train passes over the grid. However if updating from a single yellow to a double yellow trains can aproach at 70mph or more with no ATP intrevention.


When European Railway Traffic Management System (ETRMS) is installed (which is currently being tested in Wales) on trains and at lineside in this country trains will run in a similar manner to that as mentioned above. Signalling will be in the cab instead of lineside. More and Faster trains would be able to run on our overcrowded railway system! Google ETRMS for more info!