Fanuc · Series 20 CNC
This alarm indicates a Non-Maskable Interrupt (NMI) originating from the Base Board Controller (BOC) within the Fanuc Series 20 CNC. An NMI is a critical, high-priority interrupt that usually signals a serious hardware malfunction that the CPU cannot ignore, often leading to a system halt.
Click steps to track your progress.
Power cycle the CNC system to attempt a reset of the BOC and clear the NMI.
Verify stable and clean power supply to the CNC main board, checking for voltage drops or spikes.
Inspect the CNC main board for any visible damage, such as burn marks or damaged components in the BOC area.
Ensure adequate cooling inside the CNC cabinet and check for proper fan operation and clear airflow.
If the alarm persists, it indicates a hardware fault on the CNC main board related to the BOC, requiring replacement of the main board.