Rockwell Automation 1775-MX_S4A,D17756.3.1 User Manual PLC-3 BACKUP CONC(OR.DU1 - Manual (Page 45)

Operating a Backup System
Chapter 3
3-5
To troubleshoot and/or repair a faulted processor, you may have to
disconnect it.
To disconnect a faulted processor, do the following:
1. Turn off the faulted processor.
2. Disconnect the following cables:
a. For the scanner backup configuration, disconnect the backup
cable from the number one scanner module in the faulted
processor.
b. For the MX backup configuration, disconnect the
communication cables from the RCVG and XMTG connectors
on the memory communication module in the faulted processor.
3. Remove the terminal swing arms from all scanner modules in the
faulted processor.
CAUTION: To guard against damage to equipment, be careful
not to short any of the field wiring while removing terminal
swing arms. If shorts occur in field wiring, equipment may be
damaged.
The procedure for restarting a repaired processor depends on the backup
system configuration and switchover method used.
To restart a repaired processor, find the appropriate restarting method to
use in Table 3.B, then follow that procedure.
Table 3.B
Restarting Procedure Selection
If You Have This Backup Configuration:
Use This
Restarting Procedure: Page
Scanner backup if using automatic switchover with no
switchback
Method 1 3Ć6
Scanner backup if using automatic switchover with
controllable switchback;
MX backup
Method 2 3Ć7
Scanner backup if using manual switchover Method 3 3Ć7
Disconnecting
a Faulted Processor
Restarting
a Repaired Processor