26 mm 2 (10 AWG) ground wire must be used, and in all other markets a 6 mm 2 must be used. On the US market, a 5. Whether in a home or an industrial facility, this box keeps your electrical setup organized, functional, and efficient. However, the key to a safe and reliable system lies in proper installation. If it's done poorly, you risk short circuits, fire hazards, or system failure. This article details the process of installing them, which helps you comprehend distribution boxes. This document shows the methods and requirements for installing PG&E-owned, underground service cables in customer-owned, residential, terminating facilities. Each DISTRIBUTION BOX and controller must be grounded. Grounding of the units: Attach a ground wire from one of. What is the standard height for a wall-mounted distribution box? What factors should you consider when choosing the installation height? What happens if the distribution box is installed too low? What tools do you need to measure the correct height? What are the risks of not following height. This section contains the requirements for equipment and installation (including manholes, switch vaults and pull boxes) relating to the Sub-transmission, Distribution, and Control of electric power ranging from 600-Volts to 25,000-Volts, such as substations, switchgear, circuit breakers, and.