Siemens SINUMERIK 840C - Manual (Page 760)

12.93 11 Data Backup/CPU Replacement
11.1 Data area
11 Data Backup/CPU Replacement
11.1 Data area
The following data areas are backed up by a battery on the CSB module:
NC data:
• NC machine data
• Cycle machine data
• Setting data
• Tool offsets
• Zero offset
• R parameters
PLC machine data
PLC data (RAM to PLC CPU, ...):
• Data blocks
• User program
The following might cause data loss:
• Failure or replacement of the battery while the control is switched off
• NC CPU defective or removed (NC data)
• MMC CPU defective or removed (PLC MD)
• PLC CPU defective or removed (PLC data)
• Main programs and subroutines are not battery-backed. If you edit part programs in the
NCK memory (parameter area), you must save them to hard disk when you have finished
editing them. Otherwise they will be lost when you switch off the control. The operating
system offers you a workpiece called STANDARD. All data associated with the workpiece
STANDARD are automatically loaded into the NCK memory when the control is powered
up.
With SW 2 and higher, you can use MD 5025 bit 7 to set whether the last active
workpiece is to be loaded in the NCK at Power On.
With SW 3 and higher, data (e.g. IKA data) can be loaded automatically in the NCK at
Power On (similar to UMS) (see General Reset Section).
• When you have completed start-up you should save the data in the memory of the hard
disk (MMC CPU).
• The SINUMERIK 840C provides the option of storing various data sets of the same type.
To facilitate management of these files, the SINUMERIK 840C allows the use of directories
like those used on PCs. If the MMC CPU is defective all data is lost even on the hard disk.
So, it is advisable to back up user data on an external storage medium.
© Siemens AG 1992 All Rights Reserved 6FC5197- AA50 11–1
SINUMERIK 840C (IA)