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Access Siemens SINUMERIK HMI and navigate to Diagnostics > Parameter > Machine Data > Axis-specific parameters for the affected axis. Locate MD20110 (MeasuringSystemType) and MD20120 (EncoderType).

Verify that MD20110 is set to '3' (linear measuring system) or appropriate linear SSI value, NOT a rotary/multiturn encoder type (typically values 1-2 or manufacturer-specific rotary codes).

Do not set multiturn capability flags in MD20120 for linear systems; multiturn data is invalid for linear feedback.

Check MD20121 (EncoderResolution) and MD20122 (EncoderOffsetCorrection) - confirm these reflect linear measurement units (mm or inches per SSI count) not rotational turns.

Save corrected machine data via HMI > Parameter > Save or use SINUMERIK Operate interface; perform axis reference run (SRAM > Axis > Reference) to reinitialize encoder feedback path.

Physically verify the installed encoder model on the linear axis actuator; check nameplate and documentation for encoder type (confirm it is a linear SSI encoder, not a rotary/absolute multiturn encoder).

Cross-reference the physical encoder model (e.g., Siemens LMS511, Heidenhain LIP series) against the configured machine data parameters MD20120 and MD20130 (EncoderType and related fields) in the NCK configuration file.

If mismatch is confirmed, update machine data to match physical hardware: set MD20110=3 (linear) and remove any multiturn-specific parameters (e.g., MD20131 RevolutionResolution must not contain turn counts for linear systems).

Ensure the updated configuration file is compiled and downloaded to the control (Startup > Load Configuration or use SINUMERIK Operate download function).

Perform a cold restart (power cycle) of the NCK to reinitialize axis parameter validation and clear cached encoder configuration state.

In SINUMERIK Operate, navigate to System > Backup/Restore or use HMI > Service > Restart Options. Perform a 'Clear All Machine Data' or factory reset of the specific axis group to remove corrupted parameter shadows.

This operation will reset all machine data to defaults; maintain backup of valid configuration before proceeding.

Reload the current machine data configuration file (typically *_MD.def or equivalent) via HMI > Parameter > Load or NCK Editor. Ensure the file is the latest validated version for your linear SSI hardware setup.

Verify in the loaded configuration that no legacy parameter entries reference multiturn data (e.g., search MD20131, MD20132 in the parameter file for any non-zero turn-count or revolution values) and remove if present.

Save and apply the corrected configuration, then perform a full NCK restart (power cycle or HMI > Startup > Restart NCK) to validate encoder configuration against the cleaned parameter set.