Unlike traditional cable trays, slotted versions feature a series of slots or holes along their length. This design allows for improved ventilation, reducing heat buildup from electrical cables while providing easy access for maintenance and installation. ect the minimum bend ra-dius for cables as they exit the bottom of the cable tray. A rung spacing of 6 to 9 inches (150 to 230 mm) is preferable when the cable tray cont d for instrumentation and control applications that require additional protec eferred to support and protect numerous small. Slotted cable trays are essential components in cable management systems, designed to support and organize a wide variety of cables, including electrical and telecommunications lines. What is Cable Tray? A cable tray is a unit, or set of units. What Are the Main Types of Cable Trays? Cable trays are typically classified by structural design, which directly affects ventilation, load capacity, and cable support. Wire Mesh Cable Tray (Basket Tray) 5.