To ensure stable operation, perform regular maintenance: Inspect appearance for housing deformation and terminal oxidation; check mechanical components (e.g., operating mechanisms, springs) for wear; test protection devices (overload/short-circuit/undervoltage) accuracy and measure insulation resistance (≥1MΩ); clean residue from arc-extinguishing chambers, measure contact resistance (≤50μΩ) and wear; verify mechanical reliability via no-load operations (≥5 cycles), record key parameters versus historical data; adjust maintenance cycles: annually under normal conditions, shortened post short-circuit interruption.