Spellman SL600 is a compact high‑voltage DC power supply (10–1200 W range) that uses a resonant high‑frequency inverter for efficient, fault‑free operation in harsh transient and arcing environments. Common failure points on this class of units include the input rectifier bridge, output transformer winding insulation, and the resonant inverter control ICs; overheating or arcing can also damage the internal capacitors. First‑check diagnostics: verify mains voltage and polarity at the inlet, measure output voltage/current under no load, inspect for burn marks or swollen electrolytics on the PCB, and review any diagnostic LEDs or error codes indicated by the unit’s status panel.[oss-gpt-20b]