Rockwell Automation 1785-CHBM ControlNet PLC-5 Hot Backup System User Manual - Manual (Page 83)

Publication 1785-UM024B-EN-P - January 2003
Backup States B-3
– Maximum program scan time (invalid if greater than (128 x
NUT) and synchronous operational mode)
– Crossload File 1, Crossload File 2, Crossload File Low, and
Crossload File High (invalid if greater than or equal to 1000)
– Crossload over DH+ (invalid if not equal to 0 or 1)
– Requalification of dual primary PLC-5s (invalid if not equal to
0 or 1)
While in the Invalid backup state, you can set default parameters for
the optional configuration parameters by intentionally entering an
incorrect configuration value for one of the first 3 words in the
ControlNet Backup Configuration and Status File. This will force all
parameters to be set to their default values. For example, by setting
Word 0 to be equal to 0, the following optional configuration
parameters are defaulted:
• Operational Mode = Asynchronous Mode
• Equivalence Checks = All Disabled
• Designated Primary = Disabled
• Maximum Program Scan Time = 0
• Qualification Delay = 0
• Crossload File 1 = 0
• Crossload File 2 = 0
• Crossload File Low = 0
• Crossload File High = 0
• Crossload over DH+ = 0
• Requalification of dual primary PLC-5s = 0
No Control Backup State
When a valid backup configuration exists, but the PLC-5 processor is
not in Run mode, the PLC-5 ControlNet backup system is in the No
Control backup state. Both the Primary and Secondary LED’s on the
1785-CHBM cartridge are off when in this state. While in the No
Control backup state, you can switch the PLC-5 processor to Run
mode; once in Run mode, however, the processor is no longer in this
state.