I'll add a scan of my comments on your layout and calculations tomorrow.
The calcs were quite well presented, but do concentrate on the question asked since having demonstrated that 3 aspects provided the headway then a waste of time to do so again for 4 aspects given the question actually asked. Similarly you need to take a view re what to do for the stopping headway, since the year's paper did not specifically give a requirement. Certainly the calculation showing that a stopping train takes another 3 minutes and thus effectively occupies two consecutive train paths was worth doing, but you needed to relate this to the level of traffic to be accommodated rather than coming up with a value for "stopping headway" which does not directly relate to the question paper.
The biggest defects on the layout were
a) Not explicitly stating anything re "Method of Working" as per the bottom of the end notes
b) missing out required trap points (not only the Goods Loop as it changes to the Passenger loop, but also the Up sidings)
c) Missing signals- need to protect 404 from Goods Loop, 409 from Up Main)
d) Some signals not well positioned re their overlap locking (106 not ideal, 111 effectively unworkable),
e) Signal spacing etc. re the transition from 4 aspect to 3 aspect signalling
f) Interface to Stone Terminal
Overall though it wasn't too bad and I think should have passed if you could do it in the time allowed; there were some mistales and omissions but did give the impression that you basically know what you are doing.
regards,
PJW
The calcs were quite well presented, but do concentrate on the question asked since having demonstrated that 3 aspects provided the headway then a waste of time to do so again for 4 aspects given the question actually asked. Similarly you need to take a view re what to do for the stopping headway, since the year's paper did not specifically give a requirement. Certainly the calculation showing that a stopping train takes another 3 minutes and thus effectively occupies two consecutive train paths was worth doing, but you needed to relate this to the level of traffic to be accommodated rather than coming up with a value for "stopping headway" which does not directly relate to the question paper.
The biggest defects on the layout were
a) Not explicitly stating anything re "Method of Working" as per the bottom of the end notes
b) missing out required trap points (not only the Goods Loop as it changes to the Passenger loop, but also the Up sidings)
c) Missing signals- need to protect 404 from Goods Loop, 409 from Up Main)
d) Some signals not well positioned re their overlap locking (106 not ideal, 111 effectively unworkable),
e) Signal spacing etc. re the transition from 4 aspect to 3 aspect signalling
f) Interface to Stone Terminal
Overall though it wasn't too bad and I think should have passed if you could do it in the time allowed; there were some mistales and omissions but did give the impression that you basically know what you are doing.
regards,
PJW
(21-08-2014, 03:28 AM)asrisaku Wrote: Dear PJW
Yesterday I reviewed my attempt and I agree with the signal 111. On the time I attempted I took so much time to consider how to protect the points and failed to understand the operation.
Points 404, Yes again. The train coming with the diverging route to the points 404 and the braking distance would be from 40Km/h(BD=125m).
I am rusty to attempt MOD2 and it took a lot of time to think and write.
Thanks for you initial comments and look forward to seeing the rest!
Arnut
PJW