Alternative paths provided by vertical paths from the main rung of a ladder diagram, that is, paths in parallel, represent

Concept:

Alternative paths provided by vertical paths from the main rung of a ladder diagram, that is, paths in parallel, represent logical OR operations.

Below figure shows an OR logic gate system on a ladder diagram

The ladder diagram starts with ||, normally open contacts labeled input A, to represent switch A, and in parallel with it ||, normally open contacts labeled input B, to represent switch B.

Either input A or input B must be closed for the output to be energized. The line then terminates with ( ) to represent the output.

Additional information:

On a ladder diagram, contacts in a horizontal rung, that is, contacts in series, represent the logical AND operations.