What causes FANUC alarm 5231?

Machine system or function indicated by the alarm name has detected a fault. Control parameter or configuration error related to the alarm condition. Hardware component fault on the CNC or machine. Part program error or illegal operation for the indicated function. Machine interlock or safety condition not satisfied.

How do I fix FANUC alarm 5231?

1. Note the alarm number and check the Fanuc alarm screen for any sub-code or additional details. 2. Identify the specific machine system or function from the alarm name. 3. Power cycle the machine to clear transient faults. 4. Consult the Fanuc parameter or operator manual for alarm 5231 specific remedy. 5. Contact Fanuc service if the alarm persists after basic troubleshooting.

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FANUC Controller

Program/G-code · Intermediate · 30-60 minutes

Alarm 5231

Fanuc Alarm 5231 - TOO MANY FILES

Alarm 5231 occurs when the CNC's file system has reached the maximum allowable number of program files or directory entries. This limit is defined by system parameters and varies by CNC model and memory configuration. The alarm prevents further file registration until existing files are deleted or consolidated.

FANUCProgram/G-codeIntermediate30-60 minutes

5231

Fanuc Alarm 5231 - TOO MANY FILES

SYSTEM ALARM 5231

Root Cause Summary

Alarm 5231 occurs when the CNC's file system has reached the maximum allowable number of program files or directory entries. This limit is defined by system parameters and varies by CNC model and memory configuration. The alarm prevents further file registration until existing files are deleted or consolidated.

Causes and Fixes

1
Press SYSTEM softkey, then navigate to PROGRAM > DIRECTORY to view total file count. Check how many programs are registered in CNC memory.
2
Access SYSTEM > PARAM and check parameter 3107 (maximum number of registrable programs). Compare current file count against this limit. Typical limits: 0i=400, 16i/18i=400-1000, 30i/31i/32i=1000-5000 depending on memory option.
3
Delete unnecessary programs via PROGRAM > DELETE or [OPRT] > DELETE function. Prioritize removing test programs, obsolete versions, and duplicate files.
Ensure programs to be deleted are backed up externally and are not referenced by subprogram calls or macro variables before deletion.
4
If legitimate program count approaches limit, consider upgrading CNC memory option or modifying parameter 3107 if hardware allows higher value. Consult Fanuc Connection Manual for memory expansion options.

DIY Feasiblehigh confidence

Call a technician if:

·Memory clear operations fail to resolve alarm
·File system diagnostics show hardware errors
·Alarm persists after all file cleanup attempts

Prevention

Regularly delete unused programs and test files
Monitor memory usage through SYSTEM diagnostics
Implement program naming conventions to identify temporary files
Schedule periodic memory cleanup maintenance

Common Mistakes

Deleting active production programs without backup
Modifying memory parameters without understanding impact
Ignoring file system diagnostic warnings
Attempting to increase program capacity beyond hardware limits

Related Alarms

5230 5232 5240 5241

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Always verify with your machine manual or a certified technician before performing service procedures.