User Manual

Major faults Chapter 1
The SSV instruction:
Begins during prescan with the bits of all OTE instructions off and this
instruction is true. When the controller begins to run the logic, this
instruction is always false.
Writes the new values to the MajorFaultRecord attribute of this program.
Writes the values contained in the major_fault_record tag. Because the
Type and Code member are set to zero, the fault clears and the logic starts
running again.
You can use a JSR instruction to test the fault routine of a program without
creating an error (simulate a fault).
1. Create a BOOL tag that you use to initiate the fault.
2. In the main routine or a subroutine of the program, enter the following
rung, where:
test_fault_routine is the tag that you use to initiate the fault.
Fault_Routine is the fault routine of the program.
When test_fault_routine is on, a major fault occurs and the controller
executes Fault_Routine.
If you want to suspend (shut down) the controller based on conditions in your
application, create a user-defined major fault. With a user-defined major fault:
The fault type = 4.
You define a value for the fault code. Choose a value between 990 and 999.
These codes are reserved for user-defined faults.
The controller handles the fault the same as other major faults:
The controller changes to the Program mode and stops running the
logic.
Outputs are set to their configured state or value for faulted mode.
Example:
When Tag_1.0 = 1, produce a major fault and generate a fault code of 999.
Test a fault routine
Create a user-defined major
fault
Rockwell Automation Publication 1756-PM014G-EN-P October 2014 27