There are 10 branches behind the main switch, and 10 wires are led out from the bottom of the main switch. This is a very standard practice. Fix the bottom of the box in the same way of how the bracket is fixed. Primary distribution systems consist of feeders that deliver power from distribution substations to distribution transformers. This can include utility interactive PV systems, wind systems, fuel cells, energy storage systems, DC microgrids and. Distribution box parallel wiring "Parallel wiring" in electricity refers to the gathering of multiple wires together and then wiring. Additionally. In this video, we'll walk you through the process of wiring a home distribution box with a detailed connection diagram.