Typical wall-mount enclosure sizes often range from about 200 × 200 × 120 mm up to 800 × 600 × 300 mm. Freestanding cabinets commonly range from about 1600–2200 mm in height, 600–1800 mm in width, and 300–600 mm in depth. This guide explains typical wall-mount and floor-standing dimensions, how to read catalog sizes, and how to choose the right enclosure size for your layout. Do Standard Electrical Enclosure Sizes Exist? Do Standard Electrical Enclosure Sizes Exist? There is no single global chart for standard. The National Electrical Code (NEC) provides comprehensive safety standards for electrical installations, including requirements for electrical panels (main service panels and subpanels or breaker box). NEC Article 408 covers switchboards, switchgear, and Panelboards installation and applications. The standard height of an electrical box on the floor (wall receptacle) is typically 12 to 16 inches from the finished floor to the center of the box. Before you cut a single hole or mount a box, understand that these are typical heights, not universal. Wherever you may want to place your circuit box, you must follow the electrical panel mounting requirements dictated by the NEC (National Electrical Code). For the sake of brevity, The National Electrical Code outlines that a breaker box must be installed in an area that provides clearance around. FIRE ALARM VISUAL ONLY DEVICE OR A COMBINATION AUDIBLE AND 80" TO BOTTOM OF DEVICE OR NOT MORE THAN 96" TO TOP. VISUAL DEVICE NOT LESS THAN 90" TO TOP OR 6" BELOW CEILING, WHICH EVER IS HIGHER. 54" TO DIAL CENTER (NON-ACCESSIBLE).