This AutoCAD DWG file offers detailed electrical distribution board mounting plans, including both recessed and surface-mounted types. The plans detail the precise sheet metal fabrication, the layout for mounting standard DIN rail components (like MCBs/RCDs), the door hinging and. Strictly speaking, the word “Distribution Box (D-box)” can refer to two categories: electrical distribution boxes and septic tank distribution boxes. This article mainly talks about the first one. It takes the incoming power and safely distributes it to different circuits throughout your building.