26016

Navigate to Siemens HMI > Diagnostic > Machine Data. Filter by axis (e.g., 'X Axis') and locate MD 36000 (Lower soft limit) and MD 36010 (Upper soft limit).

Do not edit while machine is in AUTO mode or axes are enabled.

Verify MD 36000 < MD 36010 and both values are within physical machine limits (compare against MD 32010 Maximum rapid traverse and mechanical travel documentation).

Check MD 32000 (Axis type: 0=linear, 1=rotary) and MD 32010 (Max rapid traverse) for consistency with soft limit span; rotary axes typically allow ±360 or ±180 degree spans.

If values are incorrect, correct them in HMI machine data editor, then execute 'Save Parameters' (Ctrl+S) and perform a warm restart (Ctrl+Alt+Delete on control or cycle power to NCK module).

Restarting the control will reinitialize all axes; ensure machine is in safe position.

In HMI Diagnostic menu, select 'Machine Data' > filter axis > locate the machine data number referenced in alarm message ('%2' parameter). Note the current value and expected data type (usually DINT, REAL, or BOOL).

Cross-reference the MD number against SINUMERIK 840D parameter documentation. Verify the value matches allowed range: e.g., MD 32010 (rapid traverse) must be positive REAL > 0; MD 32000 (axis type) must be 0 or 1 (integer only).

Do not assume decimal places are acceptable in integer machine data fields.

If the value appears corrupted (NaN, extremely large negative, or fractional in integer field), manually re-enter the correct default value from machine documentation or contact OEM for factory defaults.

Save parameters and perform a Power Cycle Reset (turn off main contactor, wait 10 seconds, then power up NCK). Monitor for alarm recurrence; if alarm repeats on identical axis/MD, escalate to Siemens field service (possible EEPROM hardware fault).

Power cycle will clear transient EEPROM cache; if alarm returns after power cycle, EEPROM replacement may be necessary.

Check HMI Diagnostic > Machine Data > filter by affected axis name (e.g., 'X1' or 'GANTRY'). Locate coupling-related MD: MD 33000 (Slave axis assignment), MD 33010 (Offset), MD 33020 (Scale factor), or MD 33030 (Tolerance).

Verify coupling scale factors (MD 33020) are non-zero positive values (typically 1.0 for equal motor sizing). Confirm offset (MD 33010) magnitude is less than or equal to mechanical play tolerance. Check that slave axis MD numbers are assigned to valid physical axes.

Negative scale factors or zero values will always trigger 26016; verify against machine kinematic schematic.

If using SCANMASTER or custom kinematic, validate transformation parameters (MD 24000-24100 range) are properly loaded and match the post-processor kinematic definition; contact OEM for kinematic reference data.