What causes Siemens SINUMERIK alarm 104203?

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 104203?

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 104203 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 104203

Siemens 840D 104203 - Blank in tool identifier not allowed

Alarm 104203 occurs when the NC program contains a tool identifier (T-word) with a blank space or improper formatting. The SINUMERIK 840D control does not accept spaces within tool names or numbers, as this violates the syntax rules for tool identification in the part program.

Siemens SINUMERIKProgram/G-codeIntermediate30-120 minutes

104203

Siemens 840D 104203 - Blank in tool identifier not allowed

Blank in tool identifier not allowed

Root Cause Summary

Alarm 104203 occurs when the NC program contains a tool identifier (T-word) with a blank space or improper formatting. The SINUMERIK 840D control does not accept spaces within tool names or numbers, as this violates the syntax rules for tool identification in the part program.

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Causes and Fixes

1
Review the NC program at the line indicated in the alarm detail display to locate the offending tool identifier.
2
Remove any blank spaces from the tool identifier. Ensure the T-word follows format 'T' followed immediately by the tool number or name without spaces (e.g., change 'T 5' to 'T5').
3
If using alphanumeric tool names, replace spaces with underscores or remove them entirely (e.g., 'T_DRILL_10' instead of 'T DRILL 10').
4
Reset the alarm, reload the corrected program, and verify proper execution with a dry run or single block mode.

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