Model the cable tray in AutoCAD MEP and then Xref the MEP drawing into AutoCAD Plant 3D. Create a cable tray catalog using the Catalog Builder application within the Spec Editor, see the links below:. At its heart, Cable Tray Design, Layout means choosing and setting up cable trays to hold and protect electrical and data cables. Cable trays give cables a clear path. We use different types of trays for different jobs: Ladder. You can draw cable tray and conduit runs in order to form complete electrical networks. In the software, a run is the cable tray or conduit parts that encase or support wires, bringing them from one point, such as a junction box or a panel, to another point, such as the junction with another run. Each cable tray type performs a different function and comes in various materials such as aluminum. A cable tray layout drawing is a technical document that details the installation of a cable tray system to manage and protect electrical and signal cables in construction projects.