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Navigate to Siemens HMI > Maintenance > Machine Data > Axis-specific parameters. Locate MD 36020 POSITIONING_TIME for the affected axis (typically 0.5-2.0 seconds standard).

Increase MD 36020 incrementally by 0.2-0.5 second steps. Start with value of 1.5 seconds if currently under 1.0 second.

Do not exceed 5.0 seconds as this degrades cycle time significantly.

Run a G09 exact stop block and monitor actual axis settling time via Diagnostics > Axis > Position error display. Confirm settling occurs within new MD 36020 value.

Test full production program with new timing. If alarm clears on all G09 blocks, parameter adjustment resolved the issue.

Physically jog the axis to check for grinding, stuttering, or stiction. Listen for unusual servo motor noise indicating mechanical resistance.

Disable automatic tool changers and spindle rotation before manual axis jog.

If mechanical binding suspected: Clean lubrication paths, inspect ballnut preload, and verify axis encoders read smoothly during manual jog. Replace worn components if detected.

Access MD 36110 KPROP and MD 36111 KSUP in Maintenance > Machine Data > Axis parameters. Compare to commissioning baseline or Siemens reference values for machine type. If values are below 50% of reference, increase by 10-15% increments.

Excessive gain increase (>120% baseline) causes axis oscillation and servo faults.

Execute axis servo tuning diagnostic via HMI Diagnostics > Axis > Tuning function. Observe step response settling time and verify alignment with MD 36020 POSITIONING_TIME.

Review MD 36010 STOP_LIMIT_FINE value in Maintenance > Machine Data > Axis parameters. Verify it is ≥ 0.01mm (linear axis) or ≥ 0.1° (rotary). Values <0.005mm are typically unrealistic for standard SINUMERIK servo systems.

Cross-reference machine encoder resolution (MD 32010 ENC_RESOLUTION or MD 32020 for feedback). Calculate minimum achievable tolerance: tolerance should be 5-10× encoder resolution minimum.

If MD 36010 is tighter than encoder resolution × 10, relax the tolerance incrementally (e.g., 0.01mm → 0.02mm for linear axes). Re-run exact stop blocks to verify alarm clears.

Coordinate tolerance change with process requirements; do not loosen below part drawing specifications.

Monitor NCK trace via HMI Diagnostics > Measuring > Position deviation during G09 moves. Confirm actual position error stays within relaxed MD 36010 window before MD 36020 timer expiration.