Outlook and meaning.
|Red light: Stop|
|Yellow light: Proceed|
These are very special signals because they can be big or small
signals (see shunting signals for GB big movement and KB small movement). They can't
change the mode. A train holds its mode when passing the signal.
These signals are mostly used in yards. They protect one track and are used together with a common main departure signal. The signal are never used for the wrong main signalling and so they never flash.
1) a train is leaving the yard
2) a train enters the yard
3a) a train enters the yard on a occupied track
3b) a train enters the yard on a occupied track
4) a train shunts in the yard
5) a train enters the yard
6) a train is leaving the yard