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Full Version: Treadles and Track Circuits Occupied entry for Approach Control
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Hello Peter,

I believe you have clarified this before but need confirmation with respect to the following with respect to treadles:

For the entry for Approach Control it would be track circuit and time entry Or xx treadle operated w xx occ - in other words one entry or the other. Any entry under Remarks.

Thank you & Regards
Basically YES; one entry or the other.

If they have given you a treadle a suitable distance prior to the signal for approach release (i.e. under 100m for a PL, a distance similar to that of the ROL beyond next signal for a Warning, or a few hundred metres for a MAR route) then I'd take that as a hint that you are supposed to use it (but also see what is recorded in the route box).

Otherwise use the TC with a suitable time (and yes the timer is proved "not operated" in the signal in rear.....)

A treadle should generally be used in combination with the track circuit in which it is situated; the "treadle pressed" condition is stored (memorised) so that the signal does not get replaced if the treadle rises up between axles passing over it. There is no need to time the TC occupancy. If you want to look really smart then remember that the routes reading to the approached released signal as an exit should prove "treadle normal" i.e. not pressed; to ensure that any false approach released by it having become stuck is at least protected by the signal; in rear held to red.

If your CT has a specific column for the entry then use it; in th case of treadle then I think the track named in the appropriate columnwith a #note that is then explained to be "treadle operated, non replacing" in the Remarks column is the thing to do.

PJW
Hello Peter,

Thank you for your reply.

Regards