Allen-Bradley 1756-CNB/E, Руководство пользователя

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Publication 1756-UM523F-EN-P - December 2006
Configure and Program the Controller 67
Be Aware That Finalizing Edits Removes Your Original Logic
The controller removes the original logic when you finalize all edits in
a program. If your changes cause a major fault and a switchover, the
new primary controller also faults. That is because there is no original
logic to go back to. For example, the new primary controller cannot
untest the edits.
Decide How You Want to Set Aside Unused Memory
When the secondary controller receives crossload data, it first buffers
tag data in a quarantine section of memory. When it has all of the data
and knows it is valid, it moves the data into the main memory area.
That is why a redundant controller requires twice as much memory
for tags as a nonredundant controller.
Finalize all edits in program.
This happens even if you set the
controller to untest edits on a
switchover.
IMPORTANT
We recommend that you leave the Memory Usage slider in the
middle, default position.