Carbon steel used for cable trays shall be protected against corrosion by the following processes: Hot-dip galvanized zinc after fabrication in accordance with ASTM A123/A123M, Coating Grade 65 with an average zinc coating weight of 460 g/m2 per side or coating thickness of 0. 065 mm. 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. The galvanized coating should be continuous, uniform, complete, and practically smooth. Dull or light grey areas of uneven coloring are permissible. In many industrial, infrastructure and energy projects, the question is no longer whether to use metal cable trays, but. 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. ckling, re-rinsing, fl uxing, drying and hot-dipping.