
RelayLike Instructions
Chapter 9
9-8
Use branching instructions when you want several parallel sets of
conditions to make an output action possible. A program with branching
says, “If this set of conditions is true, or if that set of conditions is true,
perform the following action.” Branching allows two or more paths to
reach the same output destination.
True
C2
C1
A
False
Here two conditions are parallel. As long as one of the conditions (C1 or
C2) is true, a continuous path to the action exists. Therefore, the action
is performed.
True
True
C3
C1
A
False
True
C4
C2
Here are two sets of parallel conditions. If either set of conditions are true,
the action is performed.
010
00
010
00
110
10
110
12
This illustration shows a program rung with branching, as it would
appear by the 1770-T3 terminal display. You create a branch by using
two different branch instructions. These are the Branch Start and
Branch End instructions.
Branching Instructions