The trough cable tray is a fully enclosed cable tray. A perforated cable tray—also called a ventilated trough tray —features a solid bottom with regularly spaced ventilation holes and continuous side rails. Cable trays are used as an alternative to open wiring or electrical conduit systems, and are commonly used for cable management in. Trough cable tray uses: It protects cables from dust and light debris. Adding a lid makes it even more protective. It is most suitable for laying.