Sanding system controls

[PJW]

You should not expect to pass the exam by memorising answers - you need to be able to demonstrate to the examiners that you HAVE READ, UNDERSTOOD AND ANSWERED the question. Not answered last year's question.

Sequential operation is where you put additional controls on a track section so that it does not go clear until after a time delay unless the next track is occupied. For Network Rail it is detailed in the SSI8003 set of standards, but I couldn't say where off the top of my head.

I would actually interpret the question (as presented here- I have not looked up the full wording) to be a sanding system on a particular locomotive or multiple unit train rather than a mass application of sandite generally, but I don't think it changes much.  Typically a freight loco might routinely apply sand when wanting good grip for particular acceleration, particularly if encountering slipping.

Dorothy certainly has included many things that are highly pertinent to answering the question, but her most valuable advice was certainly in her last post.  Every year's questions are unique; trying to pass the exam by going in with any pre-prepared answers is doomed to failure- the examiners have made clear on many occcasions that it annoys them intensely that they get answers that are clearly that to a previous year's question and they are very much on the lookout for candidates who try that approach!  There is no substitute for carefully considering the precise question asked and using your knowledge and experience to construct an answer to it.........