Siemens SINAMICS G120 CU230P-2 HVAC Operating Instructions Manual page 291

Figure 9-3
Emptying the alarm buffer: Alarm history
The alarm history traces up to 56 alarms.
The alarm history only takes alarms that have been removed from the alarm buffer. If the
alarm buffer is completely filled - and an additional alarm occurs - then the inverter shifts all
alarms that have been removed from the alarm buffer into the alarm history. In the alarm
history, alarms are also sorted according to the "alarm time received", however, when
compared to the alarm buffer, in the inverse sequence:
● the youngest alarm is in index 8
● the second youngest alarm is in index 9
● etc.
The alarms that have still not been removed remain in the alarm buffer and are resorted so
that gaps between the alarms are filled.
Frequency inverters with Control Units CU230P-2 HVAC, CU230P-2 DP, CU230P-2 CAN
Operating Instructions, 01/2011, FW 4.4, A5E02430659B AD
Complete alarm buffer
Figure 9-4 Shifting alarms that have been removed into the alarm history
Alarms, faults and system messages
9.2 Alarms
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