Allen-Bradley 1756-CNB User Manual page 143

Action
11. Change the project revisions.
Details
A. Go offline.
B. Click the Controller Properties button.
C. Change the controller to the newer revision.
Example: Change the controller from revision 13 to revision 15.
D. Change the Revision of each local communication module to match what its revision
will be after you update its firmware.
Example: Suppose you plan to update the firmware of each CNB/D module in the
redundant chassis to revision 7.12. In that case, open the properties for each CNB/D
module in the chassis and set the revision to 7.12.
If you cannot select the new revision, then change the electronic keying to either
compatible keying or disable keying.
Update Modules and Redundant Systems
Publication 1756-UM523F-EN-P - December 2006
143