27202

Navigate to Diagnostics > Machine Data in the HMI and search for the specific MD parameter referenced in the alarm message (check the %1 and %3 values in the alarm text).

Verify the current value is not 0 or negative. Cross-reference against the machine safety documentation and PROFIsafe device configuration to confirm the correct positive address range (typically 1–2047 depending on PROFIsafe slot assignment).

Do not modify safety-critical parameters without authorization; consult machine safety validation documentation first.

Edit the parameter to the correct positive value using Siemens Automation Tool (SAT) or direct HMI parameter entry, then perform a 'Save and Compile' operation from the NCK parameter menu.

Perform a warm restart (Ctrl+Shift+Del or equivalent) or full NCK reboot to reload machine data and clear the alarm.

Open SIMATIC Automation Tool (SAT) or TIA Portal and access the HWCONFIG section to confirm the actual slot number and address range assigned to the PROFIsafe I/O module (e.g., 'PN/PN Coupler' or 'Safety Terminal').

Cross-check the slot address base (typically shown as 'Address' or 'Slot ID') in HWCONFIG against the corresponding machine data parameters (MD10100–MD10199 range or axis-specific safety MD block) referenced in the alarm.

If a mismatch is found, update the machine data address parameter to match the HWCONFIG slot assignment, or reconfigure HWCONFIG to match the intended address range in machine data.

Ensure all changes are coordinated with the safety system architect; mismatched addresses can disable safety functions.

Regenerate and download the updated HWCONFIG and machine data to the controller, then perform a warm restart.

Check the recent backup or restore history in the HMI system log (Diagnostics > System Information > Service or equivalent) to confirm whether a machine data restore or upload occurred before the alarm appeared.

If a restore is suspected, verify the source backup file by opening it in SAT or a text editor and inspecting the PROFIsafe-related MD parameters to confirm they contain valid positive values.

If the backup source is corrupted or unknown, manually re-enter all PROFIsafe address parameters based on the machine safety commissioning documentation, or restore from a known-good backup file from an earlier revision.

Do not guess at safety parameter values; always refer to the original machine design or Siemens commissioning records.

After correcting all PROFIsafe address values, save, compile, and perform a full NCK restart to validate the corrected machine data.