Rockwell Automation 1761-HHP-B30 MicroLogix 1000 with Hand-Held Programmer (HHP) - Manual (Page 110)

Chapter 6
Programming Overview
6–13
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. The output is not energized.
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.
d
a
b
e
c
In the above example, either A or B provides a true logical path to all three
output instructions.
Additional input logic instructions (conditions) can be programmed in the
output branches to further control the outputs. When there is a true logic
path, including extra input conditions on an output branch, that branch
becomes true. For instruction list programming, MPS, MRD, and MPP
instructions are sometimes needed for this connection. (See page 8–10.)
Example — Parallel Output Branching with Conditions
a
b
c
d e
In the above example, either A and D or B and D provide a true logic path
to E.