28-09-2012, 05:21 PM
Dear Alex
I've had a quick look at 133 points - which reveal in some cases that my "model answer" was wrong and you were right!
it's inevitable in the exam that you will find lots of routes calling and locking each point - often in "groups" from one signal with similar characteristics. Although this would not be done in real work, i think it's an acceptable shorthand for the exam to write "34A(M/C)/ B(S)/C(M/C" as a single entry instead of putting each true route name on a separate line. this will save you both time and space, which are both in short supply!
You have indicated that routes 352A and 348A call the points reverse - this is not the route option required - see the notes next to the route boxes on the plan
you've missed calling reverse by routes from 212 signal
There are also possible swinging overlap conditions associate with routes from 327 & 343 signals, but these start to get very difficult to spot, let alone express!
Overall, you have well captured the main conditions calling and locking the points. Take care to look for information on the plan regarding the "alternative route" which is intended.
I've started to look at the routes and remembered how my head hurt last time I looked at these - so will defer comment until later.
best wishes
Reuben
I've had a quick look at 133 points - which reveal in some cases that my "model answer" was wrong and you were right!
it's inevitable in the exam that you will find lots of routes calling and locking each point - often in "groups" from one signal with similar characteristics. Although this would not be done in real work, i think it's an acceptable shorthand for the exam to write "34A(M/C)/ B(S)/C(M/C" as a single entry instead of putting each true route name on a separate line. this will save you both time and space, which are both in short supply!
You have indicated that routes 352A and 348A call the points reverse - this is not the route option required - see the notes next to the route boxes on the plan
you've missed calling reverse by routes from 212 signal
There are also possible swinging overlap conditions associate with routes from 327 & 343 signals, but these start to get very difficult to spot, let alone express!
Overall, you have well captured the main conditions calling and locking the points. Take care to look for information on the plan regarding the "alternative route" which is intended.
I've started to look at the routes and remembered how my head hurt last time I looked at these - so will defer comment until later.
best wishes
Reuben