Provides technical requirements concerning the construction, testing, and performance of metal cable tray systems. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned. en completely installed, without damage either to conductors or structural system use 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. Cable trays play a vital role in supporting electrical cables and wires in commercial, industrial, and utility installations. es in the industrial environment.