What causes Siemens SINUMERIK alarm 104128?

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 104128?

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 104128 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 104128

Siemens 840D 104128 - PA: Error on reading number of add. axes

Alarm 104128 occurs when the control system encounters an error while attempting to read the configuration data for additional (supplementary) axes in the program or machine data. This typically indicates a mismatch between the NC program's axis specifications and the actual machine configuration, or corrupted machine data related to axis definitions.

Siemens SINUMERIKProgram/G-codeIntermediate30-120 minutes

104128

Siemens 840D 104128 - PA: Error on reading number of add. axes

PA: Error on reading number of add. axes

Root Cause Summary

Alarm 104128 occurs when the control system encounters an error while attempting to read the configuration data for additional (supplementary) axes in the program or machine data. This typically indicates a mismatch between the NC program's axis specifications and the actual machine configuration, or corrupted machine data related to axis definitions.

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Causes and Fixes

1
Access machine data and check MD10000 $MN_AXCONF_MACHAX_USED (number of machine axes) and MD10010 $MN_AXCONF_LOGIC_MACHAX_TAB (logical machine axis assignment).
2
Verify MD20070 $MC_AXCONF_MACHAX_USED for the specific channel matches the actual number of axes configured including any additional/auxiliary axes.
3
Compare the machine data settings with the physical machine configuration and ensure all additional axes (rotary, positioning, etc.) are properly defined.
Incorrect machine data can cause unexpected machine behavior or axis movement
4
If discrepancies are found, correct the machine data values, save the configuration, and perform a complete control restart (power cycle).
Always backup machine data before making changes

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