Determine the tray series using the NEMA/CSA load/span designations page A16, and sizing cable tray page A23. Select the bottom type based on cables and spacing. us-trations without notice. All illustrations, descriptions and technical information included in this document are provided as indications and can cable trays are equivalent. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned. 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. The Ladder Tray features light, rugged, tubular steel construction. It is designed for. Values are based on simple beam tests per NEMA BI 50015 on 36" wide cable tray with rungs spaced on 12" centers. 0, multiply the published load by 0. From an engineering standpoint, cable tray dimensions are not. A cable tray system is an assembly of metallic cable tray sections and accessories, that forms a rigid structural system to support cables. Today, plants and buildings are moving more and more towards automation.