Allen-Bradley 1756-CNB/E, User Manual

Page: 65 / 186

65 Publication 1756-UM523F-EN-P - December 2006
Chapter
5
Configure and Program the Controller
Introduction This chapter explains how to configure and program the controller for
redundancy.
To configure and program a controller, complete these tasks.
Plan for Online Edits
Before editing online
:
•
decide if you want to keep test edits after a switchover.
•
be aware that finalizing edits removes your original logic.
•
decide how you want to set aside unused memory.
IMPORTANT
Create and maintain only one RSLogix 5000 project for the pair
of redundant controllers. When you download the project to the
primary controller, the project automatically crossloads to the
secondary controller.
Topic Page
Plan for Online Edits 65
Configure a Controller for Redundancy 68
Configure Communications 70
Estimate the Crossload Time of a Program 74
Minimize Scan Time 76
Maintain Data Integrity During a Switchover 82
Determine the Status of Your Redundant System 87
Condition Logic to Run After a Switchover 89
Send a Message to the SRM 91
Download the Project to the Primary Controller 95
Schedule a ControlNet Network 97
Set Task Watchdog Times 100