320
Description
Process Alarm Buffers Full - controller can miss alarm transitions
Possible Cause
•
Multiple alarm variables changing state too quickly to transmit all transitions
•
Excessive alarms in queue (Plant-wide system failures)
Solution
During commissioning/maintenance:
•
Reduce the number of alarms that can change state at the same time (filter alarm variables in the application code).
During normal operation:
•
Eliminate the conditions causing excessive process alarms.
321
Description
Internal Runtime error - Process Alarms not being scanned
Possible Cause
Runtime malfunction: alarms not being scanned. Controller may restart on software watchdog timeout
due to processor overload.
Solution
•
Reload firmware and application, and restart.
•
If problem persists, replace the controller.
322
Description
Configuration Load error - Too many consumed EGD variables for Fault Tolerant EGD
Possible Cause
Number of relevant, consumed UDH EGD variables exceeds fault tolerant EGD limitation of 1400 bytes
of data.
Normal UDH EGD operation not affected; however, in the event of UDH EGD failure, some consumed variables may not be
transmitted to redundant controllers over the IONet (if applicable).
Solution
During commissioning/maintenance:
•
Reduce the amount of relevant, consumed UDH EGD data by removing the appropriate number of variables from EGD
pages.
323
Description
EGD Error - Fault Tolerant EGD activated
Possible Cause
EGD exchange timeout occurred on requesting controller. Redundant processor (if applicable) is unable
to receive UDH EGD inputs and requested that EGD data be transferred over the IONet.
Solution
•
Verify that all redundant controllers on the UDH network are receiving all expected EGD exchanges.
•
Verify that all relevant devices are powered on and producing data on the network.
48
GEH-6855_Vol_II
GEH-6855_Vol_II Mark VIeS Functional Safety Systems Volume II
Public Information