Program Fault Routine; Controller Fault Handler; Use Gsv/Ssv Instructions - Allen-Bradley Compact GuardLogix 5370 User Manual

Chapter 12 Monitor Status and Handle Faults
184

Program Fault Routine

Each program can have its own fault routine. The controller executes the
program's fault routine when an instruction fault occurs. If the program's fault
routine does not clear the fault, or if a program fault routine does not exist, the
controller proceeds to execute the controller fault handler, if one exists.

Controller Fault Handler

The controller fault handler is an optional component that executes when the
program fault routine could not clear the fault or does not exist.
You can create only one program for the controller fault handler. After you
create that program, you must configure a routine as the main routine.
The Logix 5000 Controllers Major and Minor Faults Programming Manual,
publication 1756-PM014, provides details on creating and testing a fault routine.

Use GSV/SSV Instructions

Logix controllers store system data in objects rather than in status files. You can
use the Get System Value (GSV) and Set System Value (SSV) instructions to
retrieve and set controller data.
The GSV instruction retrieves the specified information and places it in the
specified destination. The SSV instruction changes the specified attribute with
data from the source of the instruction. When you enter a GSV or SSV
instruction, the programming software displays the object classes, object
names, and attribute names for each instruction.
For standard tasks, you can use the GSV instruction to get values for the
available attributes. When using the SSV instruction, the software displays only
those attributes you are allowed to set.
For the safety task, the GSV and SSV instructions are more restricted. Note
that SSV instructions in safety and standard tasks cannot set bit 0 (major fault
on error) in the mode attribute of a safety I/O module.
For safety objects, Table 36
using the GSV instruction, and which attributes you are allowed to set by using
the SSV instruction, in the safety and standard tasks.
ATTENTION: Use the GSV/SSV instructions carefully. Making changes to
objects can cause unexpected controller operation or injury to personnel.
Rockwell Automation Publication 1769-UM022C-EN-P - June 2018
shows which attributes you can get values for by