Bulb working status (PRX6000 and 8000). Methods: A piece of white paper in the work area, such as the appearance of Arc shadow, change the corresponding light bulb. -Disinfection handle in place. Method: Two clicks were installed.More than 40 hours later, the cotton filament was still glowing, and Edison knew he had solved the problem. Light bulb sales began in 1880, and the first full introduction of Edison's lighting system in London was Holburn Viaduct in 1882. Cleaning: Wash the appearance with weak alkaline solvents (soapy water), avoid using chlorine-containing lotion (wound metal) and alcohol lotion (wound plastic and paint).