How should pan rotation concentricity be evaluated when buying an automatic cooking machine?

Judge wok concentricity under real cooking conditions, not from a brochure figure. Watch the tossing trajectory with product inside, frame vibration, and how precisely the pan re-indexes after each stop. Run several no-load and batch-loaded rotations, then measure rim runout with a dial gauge or displacement sensor, comparing the peak reading against the maker's promise. If the wok lifts out for cleaning, refit and relock it repeatedly to confirm concentricity holds every time; otherwise expect scraping, scorched spots, or uneven stir-frying on site.