The Yaskawa SGDA‑02AS is a single‑phase AC servo drive from the Sigma II series, rated at 200 W (≈0.27 HP) and designed to control SGM servomotors with incremental or absolute encoder feedback. Common failure points for this class of drives include power supply voltage drops, capacitor degradation on the input filtering board, overheating of the MOSFET output stage, and loss of encoder signal integrity due to cable insulation breakdown or connector corrosion. First‑check diagnostics: verify 200 V AC input is within spec and stable; inspect all capacitors for bulging or leakage and replace if necessary; confirm motor/encoder wiring continuity and proper grounding; review the drive’s diagnostic LEDs or error codes for indications of overcurrent, overtemperature, or encoder fault.[oss-gpt-20b]