Deadlocking of Points

[arpan_singhania]

Can Anyone explain me the term "deadlocking of points"?

[PJW]

Can Anyone explain me the term "deadlocking of points"?

Generally applied to the track circuit(s) which other cover the immediate area of track within which the points are situated- starting prior to the tips of the switch rails and extending on both legs of the turnout sufficiently far that the extents are sufficient to prove clearance from a train on the "other" divergence beyond the junction.

It means that whenever this track section is occupied the points are ALWAYS locked; there is no condition applied; i.e.
1. the locking is not route locking" (it is not dependent on any route having been set),
2. neither does it depend on the lie of the points (it locks from Normal to Reverse and also locks from Reverse to Normal)
3. similarly the locking is not removed by any other condition, for example by the lie of another point end (as would be the case perhaps in a complicated junction area and there are other points within the distance the track circuiting needs to prove clear for the safety of moves over the point being considered- the other track is "conditionally foul".

Different people may use the term dead locking slightly different from each other, so beware. The bare minimumum would be 1. so "dead locking" definitely means "irrespective of route setting". Whereas I would include also 2 and 3 in the term, not everyone would, but some might include 2 not 3 and others 3 not 2.

Indeed in some contexts I myself might use the expression that a foul track locks the points dead (meaning 1) "both ways", but I wouldn't go so far as to say that this locking was "dead track locking", because I would separately categorise as "foul track locking". It is a nice (=fine) distinction I agree, but sometimes in language the use of a term does need to take into account the wider context in which it is being used and the distinction that is being conveyed within that context.

[arpan_singhania]

Thank you Peter.