Bi-directional signalling

[Revolution Ben]

Hello all,

 

A quick signalling question....

 

The other day I was at Souldrop on the Midland main line where there are up and down fast lines, and a freight relief line that takes a slightly less steep route over Sharnbrook.

 

When I took this photograph I noticed that the southbound signal is at yellow, and remained yellow even as a northbound freight came through. Should it not have been at red, since proceeding past this signal would have resulted in a head-on collision...?

 

 

 

cheers

 

Ben A.

[meld]

Hi Ben,

 

The Signal 'WH 37x R' is a modern day 'Distant signal' as 'WH 37x is the ( next ) Stop signal further down the line,

 

The Signal shown can only show 1 yellow, 2 yellow & Green aspects.

 

Also as it is a 'Single line' the signal box would set a set of switches to the direction preference to allow correct signalling in the direction of travel required - all Controlled Signals allowing movement onto and off from the single line in the oposite direction would automatically be set to Danger

 

HTH

 

Mike

 

Edit - better explanation added

[Revolution Ben]

Hi Mike

 

Thanks for the explanation - now I know!!

 

cheers

 

 

Ben A.

[beast66606]

Also as it is a 'Single line' the signal box would set a set of switches to the direction preference to allow correct signalling in the direction of travel required - all Controlled Signals allowing movement onto and off from the single line in the oposite direction would automatically be set to Danger

 

Mike,

 

It's controlled from West Hampstead PSB so it's probably all done through locking with no manual intervention required, the signals only clear for right direction movements, as appropriate as you say.