The Cincinnati Milacron PSR 452 507500 is a 230‑V/75‑A servo power supply used to feed spindle drives and motor controllers. Common failure modes for this unit include degraded electrolytic capacitors on the output side, overheating of the internal transformer or rectifier bridge, and wear or burnout of the main relay contacts; these often manifest as voltage sag, excessive heat, or intermittent operation. First‑check diagnostics should verify that the 230‑V input is stable and within spec, inspect the power supply for visible signs of burnt components or bulging capacitors, and test the output rails with a multimeter while the unit is powered to confirm proper DC levels and continuity of the relay contacts.[oss-gpt-20b]