10 (B) (1), the smallest size single conductor allowed to be installed in a cable tray is 1/0 AWG. According to NEC Article 392. 1 (C) provides the designators for raceway trade sizes. All conductors of a circuit, including the neutral and equipment grounding conductors, must be run in the same raceway. Cable tray systems provide a safe, organized, and flexible method for supporting insulated conductors and cables in commercial and industrial electrical installations. When properly selected and installed, cable trays simplify routing, improve accessibility, and support future expansion while. This action will open submission form. This is a well built tray with easy to follow instructions. Are you a Rewards Member? Yes Helpful? maintain spacing or to keep cables in place when the tray is 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. NEC Article 392 explains cable trays, their components, appropriate wiring methods for cable trays, and instances where they are and are not permitted for use. My favorite cable management solutions are listed below, roughly in order of importance.