Learn about the common symbols and conventions used in relay logic and ladder diagrams for electrical controls, and how they can help you read and understand control circuits.

Scope: This Standard sets forth principles governing the formation of graphical symbols for logic diagrams in which connections between symbols are generally shown with lines. Definitions of logic ...

I prefer not to use symbols when doing a logical diagram. I've seen diagrams with dozens of different symbols used, presumably because the author found the latest vendor stencil, all of which were ...