FG Elektronik SNT5‑20 is a modular industrial power supply module designed for use in custom card frames and control panels; it typically delivers 5 V or 12 V DC output from a 230 VAC input with integrated protection circuitry. Common failure modes on this model include burned-out rectifier diodes, degraded filter capacitors, and failing MOSFETs due to thermal overload, as well as connector corrosion in the custom pin‑out used by Klotz Digital. Initial checks should verify the AC mains voltage and polarity, test output rails with a multimeter while the unit is powered, inspect for visible signs of overheating or component damage, and review any error codes logged on the host controller.[oss-gpt-20b]