Siemens SINAMICS G120 Operating Instructions Manual page 357

The acknowledgment has no effect as long as none of the causes for the faults in the buffer
have been removed. If at least one of the faults in the fault buffer has been removed (the
cause of the fault has been removed) and you acknowledge the faults, then the following
happens:
1. The inverter accepts all faults from the fault buffer in the first eight memory locations of
the fault history (indexes 8 ... 15).
2. The inverter deletes the faults that have been removed from the fault buffer.
3. The inverter writes the time of acknowledgment of the faults that have been removed into
parameters r2136 and r2109 (fault time removed).
Figure 9-8
After acknowledgment, the faults that have not been removed are located in the fault buffer
as well as in the fault history. For these faults, the "fault time coming" remains unchanged
and the "fault time removed" remains empty.
If less than eight faults were shifted or copied into the fault history, the memory locations with
the higher indexes remain empty.
The inverter shifts the values previously saved in the fault history by eight indexes. Faults,
which were saved in indexes 56 ... 63 before the acknowledgment, are deleted.
Deleting the fault history
If you wish to delete all faults from the fault history, set parameter p0952 to zero.
Converter with CU230P-2 Control Units
Operating Instructions, 04/2015, FW V4.7 SP3, A5E34257946B AB
Fault history after acknowledging the faults
Alarms, faults and system messages
9.4 Faults
357