Fuji Electric AP270 Drive is a low‑voltage AC variable frequency drive used to control motor speed and torque in industrial processes. Common failure modes for this class of drives include rectifier diode failures, DC bus capacitor degradation, inverter MOSFET burnout, and overheating due to inadequate ventilation or excessive load. Initial diagnostics should verify the incoming 48 VDC supply voltage and current, inspect the heat sink and fan for proper operation, and review any fault codes displayed on the drive’s LCD or communicated via Modbus/Profibus. If power is stable, check the motor wiring continuity and confirm that the drive’s output impedance matches the connected motor specifications.[oss-gpt-20b]