All fittings have inte-grated joint plates with additional beading to protect the cables. 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. cable trays are equivalent. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned in this technical guide only apply to our own cable management ranges and cannot under any circumstances be transposed to si osure, overheating or. 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. Question 1: Can mechanical utility piping or tubing containing water or compressed air be installed in cable trays with electrical cables? Answer: No. Cable trays are a support system for electrical cables, power, signal, and communication and optical fiber cables. Tray can be manufactured in various types of material including aluminum, steel and fiber and other nonmetallic materials.