Siemens Sinamics S120 Function Manual page 729

When saving, all data are backed up from the NVRAM.
NOTICE
Backing up NVRAM data
The backup of the NVRAM data to the memory card is also possible when the pulses are
enabled. However, if the drive is operated when NVRAM data are being transferred, then it
is possible that the backed up data are not consistent with the NVRAM data.
Restoring NVRAM data
With p7775 = 2, the NVRAM data are transferred back from the memory card into the
Control Unit. When restoring you decide which data you require and want to copy.
There are two reasons that necessitate the NVRAM data to be restored.
1. Replacing the Control Unit
2. Specific restoration of the NVRAM data as it is possible that there are data errors.
When restoring, the Control Unit always searches first for the "PMEMORY.ACX" file. If the
file is available with a valid checksum, then it is loaded. If a "PMEMORY.ACX" file is not
found, the Control Unit searches for a "PMEMORY.BAK" file, and if the checksum is valid
then this is loaded.
Replacing the Control Unit:
If a Control Unit has to be replaced, then this is identified by SINAMICS as a result of the
modified Control Unit serial number. After the POWER ON, the NVRAM of the Control Unit is
first deleted. The new NVRAM data are then loaded.
NVRAM restoration:
A specific restoration of the saved NVRAM data is initiated by setting p7775 = 2. The original
file in the NVRAM is first deleted. If the file "PMEMORY.ACX" is available with a valid
checksum, it is loaded to the NVRAM.
The following data is not imported again:
● Control Unit operating hours counter,
● Control Unit temperature
● Safety logbook
● Crash diagnostics data
Drive functions
Function Manual, (FH1), 01/2012, 6SL3097-4AB00-0BP2
Basic information about the drive system
12.6 Backing up the non-volatile memory
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