Understand Temperature Monitoring and Fault Behavior

1756-RM3 redundancy modules monitor temperatures and act as the temperature reaches critical thresholds.
See the following table to understand temperature monitoring and fault behavior.
IMPORTANT:
If you follow the recommended limits for ambient temperature and apply the required clearances around the chassis, redundancy modules should not reach temperature limits.
For temperature specifications, see the ControlLogix and GuardLogix Controllers Technical Data, publication 1756-TD001.
1756-RM3 Temperature Monitoring
Status Message on Front Display
Fault
Result/Action
Over Temperature
Minor recoverable
Fault code 0x6
The fault does not impact the redundancy state. Once the temperature cools to normal, clear the minor recoverable fault.
Critical Temperature
Major recoverable
Fault code 0x5
The fault causes a disqualification and switchover. Once the temperature cools to normal, clear the major recoverable fault.
CPU Internal Thermal Fault
Major nonrecoverable
Fault code 0x2
The module shuts down and causes a disqualification and switchover. To recover from the fault, reset the module. If the module restarts sooner than it cools to normal temperature, the module logs additional faults according to its current temperature.
For information about how to view faults, see Redundancy Module Faults.
Provide Feedback
Have questions or feedback about this documentation? Please submit your feedback here.
Normal