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Module 1 2012 paper. Q1 attempt
#1
Question 
Hi All,
I will be taking the module 1 exam in October for the first time. I have given a go at answering a question from 2012 module 1 exam. I would appreciate any feedback at all. I just need to know if im on the right track, and where I need to scratch up on. There will be plenty more posts leading up to the exam date on past questions attempted.

Thanks for your patience Big Grin


Attached Files
.docx   MOD1 2012 question paper. Answers 1.docx (Size: 215.7 KB / Downloads: 12)
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#2
A quick reply. First comments is I do not feel there is enough of an answer for parts B and C. A technique is spend on minute per mark.

Overall, the response does not really deal with safety. For example, the length of possession does not necessarily affect the risk of overrun. The workload planned does and having a suitable reversion strategy with spare slots to recover is a suitable mitigation.

It could be considered that small stages is a riskier strategy based. With a prolonged closure, the new equipment, if it is being replaced, can be built/installed and tested before the track changes take place. There would be no changes to the equipment, just connecting and testing. Small changes require more effort (manpower, logistics) and frequent modifications to the existing. There is a higher risk of unintended consequences (wire deg, old kit), errors (not to modern standards) etc.

The questions asks for the two approaches to be directly compared. WOuld expect a three column table, rahter than five,
* Risk
* Big Bang
* Stages.

For example,
Risk - complexity
Big Bang - Easier to manage as one team and continuous work over a short period, domain knowledge.
Stages - Duration likely to be far longer, loss of critical staff, domain knowledge lost.

Feel free to PM me but am not sure the question has been answered sufficiently and from a Mod 1 perspective.

Jerry
Cyclisme24
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#3
I had something like this on a project last year.
The P-way contractor wanted the equipment cases out the way in good time so they could use nights for pre-work before the main commissioning. The TOCs would not accept even weekend blockades to do the migration. We were left with 10 overnights (3 blocks of fri/sat/sun) each just a few hours. These are some points from my experience related to the stageworks approach:
*There is a risk that any one of those nights might overrun - many stages higher risk;
*There is a greater risk with short possessions that they could be lost altogether - we lost one because late running trains at the end of the evening meant that handover was to late to start work. Once this happens the whole sequence is at risk.
* The new equipment room needs to be able to run all the existing railway and all the new layout - it may be costly to provide any additional space, equipment and power to run today's railway from the new location, and then abolish it a few weeks later.
* there is greater complexity in the design; all the stage states have to be fully considered and planned before the first design starts.
* Potentially the existing railway is to legacy standards and if you're doing stageworks you have to resolve how to have a new equipment room to new standards running legacy railway equipment safely.
* sequential design stages take longer to design, check and approve. Both in hours spent and in timescale. It cannot be done in a shorter time by putting more designers on the job. If you can't keep the same designer(s) on every stage of the design then there could be a mis-understanding and significant incompatibility somewhere.
* There is usually a necessity for overlapping design i.e. the next stage's design is begun before the previous had been commissioned. Overlapping design means there is a risk changes to one stage are not correctly carried forward.
* if the new equipment room is relocatable (portacabin style, not brick-built) it would be possible to build and wire everything internally and fully pre-test off site. This significantly reduces the workload on commissioning for testers. This is easier if the location only has the final state to test, hard to impossible to use this method to pre-test significant stageworks.
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#4
Thank you for your replies,
I will give this question another go, with the comments taken on board.
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#5
HI,
I have given this another go. If anyone could review this and give me feedback again I would be grateful. I have concentrated more on answering the question based on the marks available, whilst taking in the comments previously made. Hopefully this comes across.

Thanks
T


Attached Files
.docx   2012 Q1 mod1. TF.docx (Size: 26.52 KB / Downloads: 11)
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#6
Sections B and C are better but would be more so with a greater safety focus. I would add, soak is not the same as testing.

The first section, A, is far too long. It does not compare and contrast (that is what is asks you to do). Read the question carefully, use the planning time to your advantage and ensure the answer you write is to what the examiners are asking for.

For example:
A single closure means a single set of design whereas stageworks requires many layers of design. This means errors or deferred works can affect design rework potentially meaning changes don't get incorporated or on-site changes are not captured leading to errors or further cancelled work on site.

Stages are not always small, "big bang" not always big. Quoted risks need to be apt for the subject. Arc welding may be an occupational risk but not really appropriate for this question in Mod 1.

Jerry
Cyclisme24
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#7
(21-08-2017, 10:13 AM)Jerry1237 Wrote: Sections B and C are better but would be more so with a greater safety focus. I would add, soak is not the same as testing.

The first section, A, is far too long. It does not compare and contrast (that is what is asks you to do). Read the question carefully, use the planning time to your advantage and ensure the answer you write is to what the examiners are asking for.

For example:
A single closure means a single set of design whereas stageworks requires many layers of design. This means errors or deferred works can affect design rework potentially meaning changes don't get incorporated or on-site changes are not captured leading to errors or further cancelled work on site.

Stages are not always small, "big bang" not always big. Quoted risks need to be apt for the subject. Arc welding may be an occupational risk but not really appropriate for this question in Mod 1.

Jerry


Talking from (very) recent experience, if you are going to replace part of a large complex RRI interlocking by putting a new RRI in an adjacent REB and therefore need to test routes, point calling and locking and approach locking lookback from the one to the other, do make sure that you have arranged an adequate possession to enable this to be achieved.

Do design the changeover in the old relay room so as to minimise the number of changes, rather than design it with the focus that it is so important that the contacts of relays are arranged in alphabetical order of routes.   
Where a circuit is spread over many sheets from fuse to relay coil, do provide all of the relevant sheets even if they are unaffected so that those on site can actually know what any particular cut-in is likely to affect

Also if expecting the testers to cope with doing the task piecemeal in white periods of a few hours each night, do plan it well ahead and produce the design that enables this and clearly shows what is to be booked back into service having been changed and fully tested so that trains can be run safely the next day.  If it is all too complicated to have sorted it out well prior, how is it reasonable to expect those working nights at the coal face to  do it against the deadline of the next day's service..........
PJW
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#8
(21-08-2017, 10:13 AM)Jerry1237 Wrote: Sections B and C are better but would be more so with a greater safety focus. I would add, soak is not the same as testing.

The first section, A, is far too long. It does not compare and contrast (that is what is asks you to do). Read the question carefully, use the planning time to your advantage and ensure the answer you write is to what the examiners are asking for.

For example:
A single closure means a single set of design whereas stageworks requires many layers of design. This means errors or deferred works can affect design rework potentially meaning changes don't get incorporated or on-site changes are not captured leading to errors or further cancelled work on site.

Stages are not always small, "big bang" not always big. Quoted risks need to be apt for the subject. Arc welding may be an occupational risk but not really appropriate for this question in Mod 1.

Jerry

Talking from (very) recent experience, if you are going to replace part of a large complex RRI interlocking by putting a new RRI in an adjacent REB and therefore need to test routes, point calling and locking and approach locking lookback from the one to the other, do make sure that you have arranged an adequate possession to enable this to be achieved.
   
Also if expecting the testers to cope with doing the task piecemeal in white periods of a few hours each night, do plan it well ahead and produce the design that enables this and clearly shows what is to be booked back into service having been changed and fully tested so that trains can be run safely the next day.  If it is all too complicated to have sorted it out well prior, how is it reasonable to expect those working nights at the coal face to  do it against the deadline of the next day's service..........

Where a circuit is spread over many sheets from fuse to relay coil, do provide all of the relevant sheets even if they are unaffected so that those on site can actually know what any particular cut-in is likely to affect.

Do design the changeover in the old relay room so as to minimise the number of changes, rather than design it with the focus that it is so important that the contacts of relays are arranged in alphabetical order of routes.

..and do fully correlate the job before you start if you want to prevent getting one train into the side of another!
PJW
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