This document provides specifications for various distribution boxes including dimensions, mounting sizes, and number of ways. Wiring diagram shows both PNP and NPN wiring. Dimensions are shown in mm (in. It is a vital part and central hub of any electrical system. The hub distributes electrical power from a single input source to various circuits throughout a. trial applications. It integrates power distribution, protection, and monitoring capabilities, and is responsible for distributing power to entire commercial or residential. This guide provides information on how to select the appropriate Distribution Box for Electric project.