Common enclosure sizes include wall-mounted boxes for compact setups and floor-standing cabinets ranging from 24”x24 ?to 48”x72 ?for extensive components. Large electrical power distribution boxes come in several sizes—single-gang for one device, double-gang for two, and so on. Check out this quick guide: Think about how many devices you need, where you will install the box, and the environment. Picking the right size helps you stay safe, follow. Electrical enclosure sizes are not universal, but most manufacturers follow common size families. Market Scope: The analysis covers residential, commercial, and light industrial electrical. An electrical box size chart is a reference guide that lists standard dimensions of electrical boxes used in different applications.