What is a Platform Switch?
 

Please excuse me if this is a simple question...

I've always wanted to know what is a Platform Switch for?

Lots of our local station platforms have them, underneath the platform edge at regular intervals, sort of a vertical sliding switch with various settings?

Thanks

Hello Vonsworld and welcome to the forum.
The "switches" that you refer to are actually track datum plates.
Another member of the forum asked a similar question to yours some time ago.
http://www.railwayforum.net/showthread.php?t=3237
This is what the Network Rail Code of Practice says track datum plates should show:
• design level of the nearest rail of the track concerned;
• design value of the cant on the track concerned;
• horizontal design dimension to the running edge of the nearest rail of the track concerned;
• the track to which the marker refers if it is not the nearest track.

Welcome to the Forum Vonsworld. Thanks for your question and to John for his answer.

Best wishes,

John H-T.