Hot Dip Galvanized (GI) Ladder Cable Trays are metal trays with a ladder-like design, coated with a layer of zinc through the hot-dip galvanizing process. The ladder design features rungs that support and secure cables, allowing for easy installation, maintenance, and ventilation. GI ladder cable. Two hot dip galvanized steel C-Channel profile side rails with transverse ladder rungs; provides the most rigid ladder tray system. Ideal for high vibration environments. C-Channel Swage Ladder trays are prefabricated metal structures that consist of two side rails connected by individual. This publication is intended as a practical guide for the proper and safe* installation of cable ladder systems, cable tray systems, channel support systems and associated supports. The Cable Tray system is installed in electrical rooms, plant rooms, and service corridors.