What causes Siemens SINUMERIK alarm 6691?

Insufficient free space on NC memory card due to accumulated cycle files or backups. Corrupted or fragmented file system on the NC card reducing usable storage capacity. $PCMCIA_FUNCTION_MASK configuration pointing to multiple directories consuming excessive card space. Large diagnostic logs or trace files not being cleaned up regularly on the memory card. Defective or failing NC memory card with degraded storage capacity.

How do I fix Siemens SINUMERIK alarm 6691?

1. Connect to the machine via HMI and check available free space on the NC card through Diagnostics > Memory > Storage or equivalent menu path 2. Backup all critical cycle files and user data to external storage, then delete unnecessary or duplicate cycle files from the passive file system directories 3. Review $PCMCIA_FUNCTION_MASK parameter settings to verify only required directories are being saved; adjust if multiple redundant save locations are configured 4. Clear temporary files, old log files, and diagnostic traces from the NC card to free additional space 5. If space issue persists after cleanup, replace the NC memory card with a known good unit and restore backed-up cycle files

Siemens SINUMERIK codes

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Siemens SINUMERIK Controller

Servo/Axis · Intermediate · 30-60 minutes

Alarm 6691

Siemens 840D 6691 - Cycles from the passive file system cannot be saved on the NC card

There is not enough space on the NC card that the directories specified in the $PCMCIA_FUNCTION_MASK can be saved. It is possible that cycles are lost during the next booting.

Siemens SINUMERIKServo/AxisIntermediate30-60 minutes

6691

Siemens 840D 6691 - Cycles from the passive file system cannot be saved on the NC card

Cycles from the passive file system cannot be saved on the NC card

There is not enough space on the NC card that the directories specified in the $PCMCIA_FUNCTION_MASK can be saved. It is possible that cycles are lost during the next booting.

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Common Causes

Insufficient free space on NC memory card due to accumulated cycle files or backups
Corrupted or fragmented file system on the NC card reducing usable storage capacity
$PCMCIA_FUNCTION_MASK configuration pointing to multiple directories consuming excessive card space
Large diagnostic logs or trace files not being cleaned up regularly on the memory card
Defective or failing NC memory card with degraded storage capacity

Troubleshooting Steps

1Connect to the machine via HMI and check available free space on the NC card through Diagnostics > Memory > Storage or equivalent menu path
2Backup all critical cycle files and user data to external storage, then delete unnecessary or duplicate cycle files from the passive file system directories
3Review $PCMCIA_FUNCTION_MASK parameter settings to verify only required directories are being saved; adjust if multiple redundant save locations are configured
4Clear temporary files, old log files, and diagnostic traces from the NC card to free additional space
5If space issue persists after cleanup, replace the NC memory card with a known good unit and restore backed-up cycle files

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