Start your inspection by looking at the outside of the box. Open the box and inspect the wiring. Make sure the insulation looks clean and has no cracks or burns. They distribute and control electrical power to lighting, mechanical services, and essential equipment across commercial, industrial, and residential facilities. Multiple circuit breakers or fuses safeguard. This guide provides a general overview of the inspection, testing, and maintenance techniques used on switchgear and switchboard assemblies, and their associated components. Inspect circuit breakers for proper operation.