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Hi everybody,
Im not sure if i am posting this in the correct place.
i came across an Auto signal at the end of a platform today. I wanted to know how these are used in this situation.
given the headway, the trains approaching the signal / station would be running on green aspects and the signaller would have no control over trains that need to stop at the station.
some trains would stop others would run straight through.
the only way i could think of is if the driver has intructions to stop, via route knowledge or WON?
are these a common occurance?
can they be used on any lines, or just infrequent rural line?
(layout permitting of course.)
thanks
fil
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15-06-2011, 11:40 PM
(This post was last modified: 15-06-2011, 11:41 PM by Peter.)
Signals are not normally used to stop trains for their service pattern. They are there to ensure safe separation and correct routing. A train that is booked to stop at a station will only know that from the running pattern. If a starter signal can be cleared (and there is no detriment to this being done), there is no reason that it will not be by the signaller regardless whether the train is due to stop at the station. There are reasons that the signaller may not clear the signal before the train gets there and there is a reasonable certainty that the train is ready to go. An example of this is the up main signal on Didcot station which also protects the junction from Oxford. Automatic Route Setting used to clear this signal well ahead of time which then locked up the junction and several times there was a problem with the train completing station duties making the problem worse. These conditions are no different really from regulating any junction and the fact that the signal in question happens to be a starter signal as well is coincidence.
The simple answer is that there are plenty of auto starters and there is no reason for them not to be autos.
An issue that I came across with the driver having to deal with his stopping pattern with no help from the signals was related to me by a driver of the Swansea to London services. There was one train a day which stopped at Slough whereas everything else was fast from Reading to Paddington. This meant that the driver of that train had to remember the stop at Slough. There being no other obvious cue for this, it tended to create a distraction all the way from Swansea as the diver reminded himself at every opportunity that there was the additional stop. One can only wonder about how a report into a SPAD in the Bristol area would be received where the driver cites his concentration on the unusual stop a Slough as being the cause for distraction.....
