Signalling Quiz 11

[Tomnick]

I did promise to put something together a little while ago, so here goes. It's handy proof-reading of the wording of a couple of questions if nothing else . All questions refer to an Absolute Block in this case.

1. The Signalman at B has accepted a train under AB Reg 3.4 from box A. A shunt movement requires to occupy the clearing point at B - when can this movement next be allowed to do so? (4 possible answers)

2. The Signalman at B has obstructed the clearing point from box A with a shunt movement, sending (and receiving acknowledgement for) 'blocking back inside home signal' to A. Describe the actions of the Signalman at B, if the shunt movement is to be allowed to move outside the home signal.

3. With which bell signal would you acknowledge the 'obstruction danger' bell signal from the box in advance, if a train was closely approaching your section signal at speed?

4. A train, failed in section between A and B, has cleared the section by being assisted back to A. What position would the block indicator be at, and how would the next train be signalled?

5. A train, failed in section between A and B, has cleared the section by being assisted (from the rear) forward to A. What position would the block indicator be at, and how would the next train be signalled?

 

[Zoe]

1. The Signalman at B has accepted a train under AB Reg 3.4 from box A. A shunt movement requires to occupy the clearing point at B - when can this movement next be allowed to do so? (4 possible answers)

When train has stopped at the home signal.

*When there are points within the clearing point and the shunt is not going to occupy clearing point for the route set.

The train has passed beyond points in the clearing point that you need to use.

If you have received cancelling.

When the train has failed.

When the line is to be examined.

*This is the interpretation of "General Signalling Regulation 4.13.2 applies" as stated in regulation 3.4.2.

2. The Signalman at B has obstructed the clearing point from box A with a shunt movement, sending (and receiving acknowledgement for) 'blocking back inside home signal' to A. Describe the actions of the Signalman at B, if the shunt movement is to be allowed to move outside the home signal.

The signalman at box B must send blocking back outside home signal (3-3) and not allow the train to move outside the home signal until this has been acknowledged. The block instrument will remain at Train On Line.

3. With which bell signal would you acknowledge the 'obstruction danger' bell signal from the box in advance, if a train was closely approaching your section signal at speed?

You would send 4-5-5, train or vehicles proceeding without authority in the right direction.

4. A train, failed in section between A and B, has cleared the section by being assisted back to A. What position would the block indicator be at, and how would the next train be signalled?

The block instrument would be at Train On Line. The next train would be signalled by informing the signalman at Box B of the details of the next train and then send Train Entering Section. The signalman at Box B will only acknowledge this though if the line is clear up to and including the clearing point. The driver of the train must then be told the details and to pass the section signal at danger and to pass through the block section with catuion and be prepared to stop in the event of an obstruction.

5. A train, failed in section between A and B, has cleared the section by being assisted (from the rear) forward to A. What position would the block indicator be at, and how would the next train be signalled?

The block instrument would be returned to Normal once the failed and assisting trains have passed beyond the clearing point and been observed complete with tail lamp. The next train would be signalled normally.

 

[Tomnick]

Had hoped for just a couple more responses at least .

When train has stopped at the home signal.

*When there are points within the clearing point and the shunt is not going to occupy clearing point for the route set.

The train has passed beyond points in the clearing point that you need to use.

If you have received cancelling.

When the train has failed.

When the line is to be examined.

*This is the interpretation of "General Signalling Regulation 4.13.2 applies" as stated in regulation 3.4.2.

Can't pick many holes in Zoe's answers though. Just the first one - obviously the Rule Book doesn't lie, but I didn't have your second (SGI 4.13.2) and last (SGI 20) in mind; not sure whether these are a fairly recent addition to this regulation, but I've always 'known' the other four as the main ones, thinking from basic principles.

Not sure about your interpretation of 4.13.2 - I'd understood it (not clearly, to be fair) to refer to moving facing points within the clearing point before the train had come to a stand: the subject to endless debates in the past, I know. If the shunt movement wasn't going to occupy the clearing point (because facing points within the clearing point were set for another route), then it wouldn't be relevant to this question or the regulation (as long as the facing points weren't moved, thus obviously bringing the obstruction within the 'revised' clearing point). Discuss!

 

[Zoe]

If the shunt movement wasn't going to occupy the clearing point (because facing points within the clearing point were set for another route), then it wouldn't be relevant to this question or the regulation (as long as the facing points weren't moved, thus obviously bringing the obstruction within the 'revised' clearing point). Discuss!

Indeed but if it wasn't relevent then why would it be in TS3/3.4.2? It would seem that this regulation considers the clearing point to be as booked but that you can allow its obstruction by setting the points for another route.