What causes Siemens SINUMERIK alarm 104129?

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 104129?

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 104129 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 104129

Siemens 840D 104129 - PA: Error on reading number of mach. axes

Alarm 104129 indicates the NCK cannot correctly read the number of configured machine axes from the machine data. This typically occurs due to corrupted or inconsistent machine data settings, incorrect MD configuration during startup, or file system errors affecting the machine data storage.

Siemens SINUMERIKProgram/G-codeIntermediate30-120 minutes

104129

Siemens 840D 104129 - PA: Error on reading number of mach. axes

PA: Error on reading number of mach. axes

Root Cause Summary

Alarm 104129 indicates the NCK cannot correctly read the number of configured machine axes from the machine data. This typically occurs due to corrupted or inconsistent machine data settings, incorrect MD configuration during startup, or file system errors affecting the machine data storage.

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Causes and Fixes

1
Enter Service Mode and navigate to Commissioning > Machine Data > General MD.
2
Check MD10000 $MN_NUM_MACHAX - verify it matches the actual number of axes configured (typically 3-5 for mills, varies for lathes/multi-channel machines).
3
If value is incorrect or shows '0', set correct value (e.g., 3 for X/Y/Z mill), save, and perform NCK Reset.
Changing this value affects entire axis configuration - verify all axis-specific MD are properly configured before restart.
4
If unable to modify, restore machine data from backup or reload OEM default machine data and reconfigure.
Restoring defaults will erase all custom machine parameters including compensation tables.

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