24.3 DESIGN TECHNIQUES

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24.3.1 State Diagrams

We can implement state diagrams seen in earlier sections using many of the advanced function discussed in this section.

Most PLCs allow multiple programs that may be used as subroutines. We could implement a block logic method using subroutine programs.

Consider the state diagram below and implement it in ladder logic. You should anticipate what will happen if both A and C are pushed at the same time.