Rockwell Automation 1772-L8_LW_LWP_LX_LXP,D17726.5.8 User Manual - Manual (Page 136)

RelayĆLike Instructions
Chapter 9
9-10
Important: Once you press the Branch End instruction, the statement
BRANCH END OMITTED disappears.
While inserting a Branch Start instruction to an existing rung during online
programming, the actual output status (on or off) may not be the logically
expected state of the rung. This condition exists until you enter the Branch
End instruction and complete the rung.
To avoid this condition, do the following:
1. Immediately below the rung to be changed, create a new rung with
the same input logic (duplicate the rung), but do not put the output
in yet.
00
010
00
110
01
110 110
02
00
110
01
110 110
02
added rung
with no output
2. Move the cursor to the point where you want to change the logic and
insert the Branch Start instruction.
3. Insert the desired parallel logic.
4. Insert the Branch End instruction.
00
110
01
110 110
02
110
03
5. Insert the output instruction
00
010
00
110
01
110 110
02
110
03
6. Delete the original rung