Install filler plates or covers for unused spaces in panelboards. Tighten bolted bus, switch, and termination connections in accordance with manufacturer's recommendations. It provides a visual representation of. An elevator electrical wiring diagram is a visual representation of the electrical connections and components of an elevator system. This diagram is essential. Before installation, it's important to know what makes up a distribution box. Let's break it down into two main parts: the outer shell and the electrical parts inside. (See chart above according to ASME A17. For example, an 8x19 construction wire rope is formed by 52 wires that are grouped into 8 strands.