The MBE3‑50 is a 100 VA magnetic‑bearing driver/controller used in laser cutting systems such as the Trumpf L3030‑S, providing 400–500 VAC input and 400–800 VDC output to a 2 A/50 V load. Common failure modes for this class include power‑stage overheating (MOSFET or IGBT burn‑out), capacitor degradation in the DC bus, and loss of magnetic bearing alignment due to bearing wear; firmware corruption can also trigger “drive fault” codes. First‑check diagnostics: verify that the 400–500 VAC supply is within spec and that the DC bus voltage is stable; inspect all heat‑sink fins and MOSFETs for discoloration or burn marks; review any error logs on the controller’s LCD or serial interface for specific fault codes.[oss-gpt-20b]