In-track Cabling query

[Chris Osment]

Seen in the Up line at Sherborne, can someone please tell me what this 'white' cabling is for?
There was a similar set alongside it in the Down line, but without the white paint.

[Nicko]

Cross track signalling cables sprayed white to highlight position to tamper drivers

[Mike Stone]

Not sure that's what he was asking? If it was I'll ask what I think he meant - why so many cables and in that form, rather than collected together.

[Nicko]

I think the latest standard is to clip cables to sleeper rather than using orange pipes or concrete troughs

[Chris Osment]

Not sure that's what he was asking? If it was I'll ask what I think he meant - why so many cables and in that form, rather than collected together.

Indeed Why so many cables, and why arranged in this 'wriggly' format? I wondered if it was some form of induction loop/transponder for something?

[Nicko]

From angle photo is taken it is not possible to see where cables go but most appear to be connections for track circuits

[colin1501]

Not sure they are for track circuits. Aren't axle counters used on this route?

Colin

[Mike Hodgson]

It certainly looks like a form of induction loop. Perhaps to do with initiating the crossing ?

[Richard Pike]

They look like track circuit single cores. Two per rail each side of the block joint. Probably not best practice but there must be a reason for not using two cores and dis boxes.

[Frank]

Hello Mike,

that

It certainly looks like a form of induction loop. Perhaps to do with initiating the crossing ?

i`ll think, too.

So that the Engine Driver can activate the AHB with "his" Train over the induction.

A Similar Device with induction loop is here with AHB`s in use, called Automatic-HET.

[Nicko]

Sherborne is a manned cctv crossing http://abcrailwayguide.uk/sherborne-pub ... Bi-iVcgGrU

[Chris Osment]

The 'Up' line at Sherborne (the one with the white cabling) is bidirectional, whereas the Down is not. Given that there was similar cabling (but not white) immediately alongside in the Down line, then I am wondering whether it was simply part of the start/end of a 'track circuit' immediately past the crossing?

[Sharpey]

As has been mentioned before the white is just marking up to highlight the cables to tamper drivers so they are aware of them to be that little more careful around them (some would suggest that it just gives them something to aim at!)

As for the quantity of cables it does appear to be a rather ungainly way of managing track circuit tail cables. Given that there is another Insulated Rail Joint adjacent in the Down line it is not possible to cross the cables directly over at that point as that would mean having too many cables on one sleeper. It appears that they have been run to the platform face and then away from the crossing to cross them over one pair at a time at the next available clear sleeper.

With track circuit leads being doubled up (i.e. two per rail for one end of a track) it would suggest that at least the nearest side of the UP line IRJ has a feed end relay fitted thus doubling the number of leads to 4 per rail.

[RobMorel]

sprayed white by the track quality supervisor (TQS) during a walkout prior to tamping or stoneblowing, marking something to watch out for 'on the night' of on track machine use.
Although revolutionary at the time orange pipes actually prevent tamping and cause voids despite being originally used to stop cut cables, hollow bearers are now preferred or snagging- secured to sleepers themselves as shown in originl thread
http://www.unipartrail.com/assets/j2540 ... re-st1.pdf

[Danny252]

I noticed a similar set of cables past the North end of Wolverhampton platform 1 - clearly unrelated to level crossing operation in that location!