A Trough Cable Tray looks like a continuous “U” shape. It has a solid bottom and two side walls. This helps with cable ventilation to manage heat. A complete system is made up of. A perforated cable tray—also called a ventilated trough tray —features a solid bottom with regularly spaced ventilation holes and continuous side rails. Today, electrical cable trays have become an essential component in industrial and commercial construction, providing a quick, economical, and. The trough type cable tray represents a fundamental infrastructure component designed to support and organize electrical cables in commercial, industrial, and residential installations.