"Ladder Logic" internal contact set-up

Hi Everyone,

I'm working on my first PLC program and I have gotten my hands on some ladder logic I'm trying to duplicate.

I'm using SoMachine 4.1 and have started a new Ladder Logic diagram POU.

I'm curious on how do I create internal contacts.

EXAMPLE:

24v--------l START BUTTON l----------------( COIL A)-----

--------------l COIL A CONTACT 1; attached to a real output, solenoid valvel-------------l COIL A INTERNAL CONTACT TO CLOSE l----------------

Are there standards for numbering and labeling?

I'm seeing L and U inside coil contacts. Does this have an underlying meaning according to standard?

Is there a RTO function inside SoMachine 4.1