130-006D

Access Boot and Software Information

Power cycle the control and observe the boot sequence carefully. Note at which stage the alarm occurs (during initial splash screen, after NC loading, or during PLC startup). Enter MOD function and select 'System Info' to check current software version and build date.

If the alarm occurs consistently at the same point during boot, it indicates corruption in specific system components loaded at that stage.

Boot into TNCdiag Service Mode

Restart the control while holding the CTRL key (TNC 320/iTNC 530) or access the boot menu by pressing ESC during startup (TNC 620/640). Select 'TNCdiag' to enter diagnostic mode and run 'File System Check' to verify SYS: partition integrity.

Do not interrupt file system checks once started - interruption can cause further corruption requiring factory recovery.

Restore from Recovery Partition

In TNCdiag mode, select 'System Recovery' and choose 'Restore Factory Software' or 'Restore from Backup' if available. This reinstalls the NC software without affecting machine parameters if you select the appropriate option.

Always backup TNC:\system\syspar.sys and machine.cfg files to external media before recovery operations.

Reload Software from External Media

If recovery partition is corrupted, obtain the correct software version on USB drive from Heidenhain. Boot from USB using the service boot menu and perform a complete software installation following the SIK-based installation procedure.

Ensure you have the correct SIK license file and machine-specific configuration files before proceeding - incorrect software versions may cause machine damage.

Check PLC Status and Cycle Time

In MOD function, navigate to 'PLC' → 'PLC Status' to view current PLC cycle time and maximum cycle time recorded. Check for cycle time overruns (typically should be <10ms for stable operation). Review the error protocol for PLC-specific messages preceding the 130 alarm.

PLC cycle times consistently above 20-30ms indicate poorly optimized code or excessive module loading that can cause watchdog timeouts.

Boot with PLC Disabled

Access Machine Parameter 7210 (PLC active) and set to 0, or boot into safe mode to disable PLC execution. If the system alarm does not occur without PLC running, the root cause is confirmed to be in the PLC program.

Operating with PLC disabled means all machine safety logic and auxiliary functions are inactive - only use for diagnostic purposes, never for production.

Analyze PLC Program for Errors

Open the PLC program in PlcEdit or TNCopt and search for unbounded loops, recursive function calls, or marker/counter overflows. Check for runtime errors in error handling sections and verify proper termination conditions exist for all loops.

Use the PLC debugger's online monitoring to identify which program sections are consuming excessive cycle time before the crash occurs.

Restore Known-Good PLC Program

Load a previously working version of the PLC program or the machine manufacturer's original PLC code. If no backup exists, create a minimal test PLC program with only essential I/O to verify the PLC runtime environment is functional.

Always maintain versioned backups of PLC programs in TNC:\plc\backup\ with date stamps after any modifications.

Run Hardware Diagnostics in TNCdiag

Boot into TNCdiag mode and execute 'Hardware Test' → 'Memory Test' (extended test). Allow the test to run completely (may take 30+ minutes). Also run 'CPU Test' and 'Board Communication Test' to verify processor and bus integrity.

Extended memory tests will completely occupy the control - schedule during maintenance windows only.

Check Environmental Conditions

Verify control cabinet temperature is within specification (typically 5-45°C). Inspect cooling fans on the processor unit for proper operation. Check for dust buildup on heat sinks. Excessive heat can cause intermittent CPU errors that appear as system alarms.

Thermal-related processor failures often occur after specific runtime periods - note if the alarm appears after consistent operation duration.