What causes Siemens SINUMERIK alarm 109009?

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 109009?

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 109009 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 109009

Siemens 840D 109009 - Switchover: error in internal state

This alarm typically occurs due to an internal state error during a switchover, often caused by incorrect program syntax or unsupported functions. Correcting the program or verifying control options usually resolves it.

Siemens SINUMERIKProgram/G-codeIntermediate30-120 minutes

109009

Siemens 840D 109009 - Switchover: error in internal state

Switchover: error in internal state

Root Cause Summary

This alarm typically occurs due to an internal state error during a switchover, often caused by incorrect program syntax or unsupported functions. Correcting the program or verifying control options usually resolves it.

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Causes and Fixes

1
SAFETY: Stop machine and enter safe state
Press emergency stop, ensure machine is in safe position, and lock out power before investigating program issues.
2
Locate error block
Check the alarm message for the specific line or block number in the program.
3
Fix syntax
Review and correct any syntax errors or invalid commands in the identified block.
4
Test program in simulation mode
Use dry run or simulation mode first to verify corrections before actual machining.

DIY Feasiblehigh confidence

Call a technician if:

·If the alarm persists after program corrections
·If the required option cannot be enabled without assistance

Prevention

Always validate programs using simulation before execution
Ensure compatibility of G-code with the control version
Maintain proper machine safety protocols during troubleshooting
Keep backup copies of known-good programs

Common Mistakes

Overlooking the specific block number in the alarm
Failing to check subprograms for errors

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