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Input branching, Output branching – Rockwell Automation 1747-PT1, D1747NP002 Hand-Held Terminal User Manual

Page 89

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Chapter 5
Ladder Program Basics

5–5

Input Branching

Use an input branch in your application program to allow more than one
combination of input conditions to form parallel branches (OR–logic
conditions.) If at least one of these parallel branches forms a true logic path,
the rung logic is enabled. If none of the parallel branches forms a true logic
path, rung logic is not enabled and the output instruction logic will not be
true. (Output is not energized.)

Example – Parallel Input Branching

A

B

D

C

In the above example, either A and B, or C provides a true logical path.

Output Branching

You can program parallel outputs on a rung to allow a true logic path to
control multiple outputs. When there is a true logic path, all parallel outputs
become true.

Example – Parallel Output Branching

MOV

U

A

B

C

E

In the above example, either A or B provides a true logic path to all three
output instructions.