Our cable tray load calculator helps engineers and contractors design systems that comply with international standards and best practices. A properly designed and installed cable tray system will provide. 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. Safe working loads are represented graphically as shown and are based on the cable tray being continuous over four spans or more. Deflection has been limited to SPAN/200 generally, based on the end span condition as the worst case. However, on. These decisions are relatively simple and can be condensed down to four steps. Material choice T&B channel tray systems are fabricated from a corrosion-resistant metal (low-carbon steel, stainless steel or an aluminum alloy) or from a metal with a corrosion-resistant finish (zinc or epoxy). The. Hubbell's NEXTFRAME® Ladder Tray is the effective and widely used cable runway that supports and delivers bundles of cable between cabinets, racks, and closets, along walls, and suspended from ceilings.