Result Of Logical Operation

HELLO EVERYBODY, I WANT TO KNOW ABOUT RESULT OF LOGICAL OPERTION
(RLO), HOW IT HELP US FOR FAULT FINDING IN SIEMENS PLCs.PLEASE EXPLAIN RLO WITH SUITABLE EXAMPLE.

Hello kambojrakesh;
The RLO is a status bit used to construct the validity state(TRUE or FALSE) of a network.
It can alsio be used to test program execution, as shown here (from the "Programming with S7, v. 5.4" pdf manual):

You can test your program by displaying the program status (RLO, status bit) or the contents of the corresponding registers for every instruction. You can define the scope of the information displayed in the "LAD/FBD" tab in the "Customize" dialogbox. You open this dialog box using the menu command​

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To read more, download the manual from Siemens' support website.

Hope this helps,
Daniel Chartier