Attention

IronPLC supports IEC 61131-3 Structured Text excluding I/O mapping.

Ladder DiagramΒΆ

Ladder Diagram (LD) is a graphical programming language based on relay logic diagrams. It represents logic as a series of rungs connecting a left power rail to a right power rail, with contacts and coils that implement boolean logic.

Element

Description

Rungs

Horizontal logic lines

Contacts

Normally open and normally closed contacts

Coils

Output, set, and reset coils

Branches

Parallel and series connections

IEC 61131-3

Section 3.2