Allen-Bradley 1756-RM2 - Page 72

72 Rockwell Automation Publication 1756-UM535D-EN-P - November 2012
Chapter 3 Install the Enhanced Redundancy System
Complete these steps to designate the primary and secondary chassis of a
redundant pair.
1. Verify that power is removed from both chassis.
2. Apply power to the chassis you want to designate as the primary chassis
and wait for the module’s status indicators to display PRIM.
3. Apply power to the chassis you want to designate as the secondary chassis.
4. Verify primary and secondary chassis designations by viewing the module
status display and the PRI indicator.
See Status Indicators on page 227
for specific redundancy module display
information.
IMPORTANT
If both modules have power applied to them simultaneously, the module with
the lowest IP address is designated as the primary chassis and displays PRIM on
the module’s four-character display. In addition, the PRI status indicator on the
primary redundancy module is green. The secondary chassis displays either
DISQ or SYNC, depending on the state of the secondary chassis. In addition, the
PRI status light on the secondary redundancy module is not illuminated.