Rockwell Automation 1772-LV Mini-PLC - 2/15 Programmable Controller (Series B) Programming and Operations User Manual
Page 44

Fundamental Instruction Set
Chapter 5
5Ć7
The rung below uses parallel logic:
C1
False
C2
True
A
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.
C1
False
C3
True
A
C2
True
C4
True
Figure 5.2 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.
Nested Branching
The rung below shows a nested branch.
110
00
010
00
110
10
110
11
110
12
110
13
Creating nested branches is not possible because the branch end instruction
completes a branch group. But the above rung shows a single branch group
with two branch end instructions. Above, the examine-on instruction with the
address 11011 is actually a branch group within a branch group.