The Lambda PVA‑4000‑14 HB‑SPS1 is an industrial 4 kW power supply used to deliver regulated DC output for motor drives and control systems. Common failure modes include degraded output regulation due to failing filter capacitors or rectifier diodes, overheating from fan blockage or thermal overload, and transformer winding insulation breakdown that can cause shorted secondary windings. First‑check diagnostics: verify input voltage and polarity with a multimeter; inspect the unit for obvious signs of overheating (burnt smells, swollen electrolytic caps) and ensure the cooling fan is operating; then measure output voltage under no load and with a representative load to confirm regulation within spec.[oss-gpt-20b]