What causes Siemens SINUMERIK alarm 100620?

Part program contains an illegal or unsupported command for the current machine configuration. Parameter or machine data setting incompatible with the commanded operation. Required option or function not enabled on this SINUMERIK control. Incorrect axis assignment or configuration for the commanded function. Software version or compile cycle version mismatch.

How do I fix Siemens SINUMERIK alarm 100620?

1. Note the full alarm message including any parameter values shown (e.g., axis number, block number, channel). 2. Identify the program block or operation that triggered the alarm. 3. Review the SINUMERIK alarm manual for alarm 100620 to identify the specific cause and remedy. 4. Check the relevant machine data parameters referenced in the alarm. 5. If the alarm persists after correcting the program, contact Siemens technical support with the full alarm text and machine data backup.

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Siemens SINUMERIK Controller

Program/G-code · Intermediate · 30-120 minutes

Alarm 100620

Siemens 840D 100620 - Error on trying to open font file

SIEMENS alarm 100620 occurs when the SINUMERIK system cannot access or load required font files for the HMI display, typically during system startup or when switching between display modes. This alarm is commonly triggered by corrupted font files, incorrect file paths in system parameters, or insufficient memory allocation for font loading.

Siemens SINUMERIKProgram/G-codeIntermediate30-120 minutes

100620

Siemens 840D 100620 - Error on trying to open font file

Error on trying to open font file

Root Cause Summary

SIEMENS alarm 100620 occurs when the SINUMERIK system cannot access or load required font files for the HMI display, typically during system startup or when switching between display modes. This alarm is commonly triggered by corrupted font files, incorrect file paths in system parameters, or insufficient memory allocation for font loading.

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Causes and Fixes

1
Check Font Directory Structure
Navigate to /siemens/sinumerik/hmi/font on the NCU and verify all required .ttf and .fnt files are present.
Use WinSCP or similar tool to access the NCU file system safely
2
Verify File Integrity
Check file sizes and timestamps against a known good backup or factory installation to identify corrupted files.
Always backup current files before replacing
3
Restore Font Files
Copy missing or corrupted font files from SINUMERIK installation media or backup, ensuring proper file permissions are maintained.
Restart HMI service after file restoration using 'service hmi restart' command

DIY Feasiblehigh confidence

Call a technician if:

·Font files cannot be restored from backup
·System memory hardware failure suspected
·Multiple HMI-related alarms persist after font restoration

Prevention

Regular backup of HMI configuration and font files
Monitor system disk space and memory usage
Avoid manual modification of system font directories
Keep SINUMERIK software updated to latest stable version

Common Mistakes

Copying font files without preserving permissions
Modifying font paths without understanding system architecture
Deleting font files thinking they are unnecessary
Not restarting HMI services after font file changes

Related Alarms

100621 100610 100630 61000

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