2009 Signal Control Table

[NJK]

Dear Members,

I have attempted 2009 Signal control table. I have tried the following Routes 416B(M/C), 365A(M/W/C), 371D.

Layout and solution is attached for your reference. Kindly have a look and give your comments for my further enhancement.

Assumption : In the layout Clearance Point (CP) details are not given so unable to consider the fouling track for signal aspect control.

Thanks in advance.

Regards,
NJK

[Peter]

Dear Members,

I have attempted 2009 Signal control table. I have tried the following Routes 416B(M/C), 365A(M/W/C), 371D.

Layout and solution is attached for your reference. Kindly have a look and give your comments for my further enhancement.

Assumption : In the layout Clearance Point (CP) details are not given so unable to consider the fouling track for signal aspect control.

Thanks in advance.

Regards,
NJK

Wow, the first time in ages I have got the kids to bed and then been able to sit down and look at some signalling before I have fallen asleep! That said, I have only had the chance to look at one.

I must admit, I had mostly the same as you when I did this first, but then realised that a lot of what was there was probably not required.

Points first.

I think you missed 246N, just because it would be odd to have them out of step with the switch diamonds. (That said, I cannot see a way that you could have a train anywhere to go through them R after this route is set!)

For the opposing routes, bear in mind that anything going up to 406 will require the overlap for 406 to be set and locked. Given that this would require 243N and 416B(M) requires 243R, 351B(M), 365B(M) would not be opposing as they fail on the point condition. Depending whether you have overlaps for shunt routes, the same could be true of several of the shunt moves up to here.

You also have 373A(S) and B(S) in there which cannot be right as they go to different places.

That point aside, if they were opposing, you have largely got the tracks clear part right with a couple of exceptions:
For opposing locking, the tracks only go up to the exit signal of the opposing route. The tracks between the exit signal and the signal the control table are for would be listed for the exit signal.

For the call on routes, you have put that the platforms tracks will have to be clear to release the locking. This would not be the only way - them being occupied for time. So you should have something like
AC, AD, AE, BV, BU, BT, [BS, BR ----- BS or BR for t]. The bit before the dashes being in the Tracks clear col and the bit after being in the Tracks Occ for T col. This would have been the case for the main and shunt routes too (if they had been opposing).

In the Points called locked and detected section, you are right up to a point. you have noted that 237 is the hinge point for the swinging overlap, but that means that you should have put the other point conditions beyond 237 with the relevant conditions:
(235N, 234N with 237N) (232N, 236R with 237R) and the same is true of the tracks clear. the overlap includes (BU, BV w 237R) (DR, DS w 237N).

Hope that is helpful. I'll try to have a look at some of the others (children, work and wife permitting) unless someone else gets there first!

If there is anything that is not clear in this, please let me know and I'll try to answer.

Peter

[NJK]

Dear Peter,
Thank you very much for your comments. I have few clarifications. Kindly clarify it
1. Overlap is not consider for shunt routes leading to exit signal 405 (overlap is consider for shunt routes only if the exit of the shunt signal is either limit of shunt signal or independent position light signal). So for 416B(M) movements I considered opposing routes as 353B(S), 371B(S), 373A(S).
2. I considered opposing route as 371B(S), 373B(S) also because if the movement is overrun it makes head on collision with 416B(M) movements.
Kindly correct me if I am wrong.
Regards,
NJK

Dear Members,

I have attempted 2009 Signal control table. I have tried the following Routes 416B(M/C), 365A(M/W/C), 371D.

Layout and solution is attached for your reference. Kindly have a look and give your comments for my further enhancement.

Assumption : In the layout Clearance Point (CP) details are not given so unable to consider the fouling track for signal aspect control.

Thanks in advance.

Regards,
NJK

Wow, the first time in ages I have got the kids to bed and then been able to sit down and look at some signalling before I have fallen asleep! That said, I have only had the chance to look at one.

I must admit, I had mostly the same as you when I did this first, but then realised that a lot of what was there was probably not required.

Points first.

I think you missed 246N, just because it would be odd to have them out of step with the switch diamonds. (That said, I cannot see a way that you could have a train anywhere to go through them R after this route is set!)

For the opposing routes, bear in mind that anything going up to 406 will require the overlap for 406 to be set and locked. Given that this would require 243N and 416B(M) requires 243R, 351B(M), 365B(M) would not be opposing as they fail on the point condition. Depending whether you have overlaps for shunt routes, the same could be true of several of the shunt moves up to here.

You also have 373A(S) and B(S) in there which cannot be right as they go to different places.

That point aside, if they were opposing, you have largely got the tracks clear part right with a couple of exceptions:
For opposing locking, the tracks only go up to the exit signal of the opposing route. The tracks between the exit signal and the signal the control table are for would be listed for the exit signal.

For the call on routes, you have put that the platforms tracks will have to be clear to release the locking. This would not be the only way - them being occupied for time. So you should have something like
AC, AD, AE, BV, BU, BT, [BS, BR ----- BS or BR for t]. The bit before the dashes being in the Tracks clear col and the bit after being in the Tracks Occ for T col. This would have been the case for the main and shunt routes too (if they had been opposing).

In the Points called locked and detected section, you are right up to a point. you have noted that 237 is the hinge point for the swinging overlap, but that means that you should have put the other point conditions beyond 237 with the relevant conditions:
(235N, 234N with 237N) (232N, 236R with 237R) and the same is true of the tracks clear. the overlap includes (BU, BV w 237R) (DR, DS w 237N).

Hope that is helpful. I'll try to have a look at some of the others (children, work and wife permitting) unless someone else gets there first!

If there is anything that is not clear in this, please let me know and I'll try to answer.

Peter

[Peter]

Dear Peter,
Thank you very much for your comments. I have few clarifications. Kindly clarify it
1. Overlap is not consider for shunt routes leading to exit signal 405 (overlap is consider for shunt routes only if the exit of the shunt signal is either limit of shunt signal or independent position light signal). So for 416B(M) movements I considered opposing routes as 353B(S), 371B(S), 373A(S).

It depends what principles you are following (and you will have declared this on your answer in the exam). For UK mainline, the requirement is given in NR/L2/SIG/30009/E440 and talks about overlaps beinn requried where there is a shunt move up to a "destination signal". This term is defined in section 5.5 as "The destination signal may be a shunt signal, a main signal or a limit of shunt." You would of course have to determine the length of that overlap and hence what points it would need to lock so possibly affecting what is required as opposing locking.

2. I considered opposing route as 371B(S), 373B(S) also because if the movement is overrun it makes head on collision with 416B(M) movements.
Kindly correct me if I am wrong.
Regards,
NJK

I assume you mean 371C(S) and 373B(S). The destination for these is the Up Main platform. Opposing locking does not consider the effect of signal overrun. In this case would render the layout very restrictive. If it were the case that moves into the UM were not desirable with the route from 416 into the Up Branch platform, you would need to include 365C(M) and you would effectively be saying that the overlap for 407 should be longer.

Hope that helps.

Peter