61806

Access the machine data tree via HMI: Diagnostics > Machine Data > Search for MD20050. Verify the axis assignment sequence for the active channel matches the axis order in your NC program.

Do not modify MD20050 without understanding the complete machine kinematics and channel structure.

Review the alarm block number (%2) in the NC program. Cross-reference this block to identify which axes are being commanded and in what sequence.

Compare the axis identifiers in the flagged NC block against the configured axis names in MD20050 and verify no axis is being assigned to multiple channels simultaneously.

If axis order is incorrect in the program, rewrite the NC block to follow the machine's axis assignment sequence. If MD20050 is incorrect, contact machine builder or Siemens support before modification.

Check the NC program block (%2) for axis letter codes. Verify these letters are declared in the machine's axis nomenclature via HMI: Diagnostics > Machine Data > MD9000 (axis number table) or MD20060 (axis identification).

Navigate to NCK > Axis Data in the Siemens HMI and confirm the axis is configured as a linear or rotary axis with valid motor assignment and encoder feedback chain.

Verify the axis has been commissioned in the relevant channel by checking MD20070 (channel axis assignment) to ensure the undefined axis is not a typo or obsolete reference.

Correct the NC program to use only defined axis identifiers, or reconfigure the machine data to include the missing axis definition if it is intentional.

Identify the active channel number from the alarm context. Access HMI: Diagnostics > Channel > Overview to confirm which channel is executing the flagged block.

Navigate to Machine Data > MD20070 for the active channel and verify that all axes referenced in the NC block are listed in that channel's axis assignment linkage.

Multi-channel axis conflicts can cause unpredictable servo behavior if not resolved.

If the axis belongs to another channel, either move the axis reference to the correct channel program or reconfigure MD20070 to include the axis in the current channel (after verifying no hardware conflicts exist).

Reload the machine data (Utilities > Load Machine Data) and perform a soft reset (Ctrl+Reset) to synchronize the NCK interpreter with the updated channel-axis topology.