The NEC has a requirement for ladder-type cable trays. As uniform as possible, however, the Run Length Between Supports should ideally be in the range of 4 to 6 feet as indicated in the NEC design and load factor. Ladder cable tray is available in widths of 6, 9, 12, 18, 24, 30, 36, 42 and 48 inches with rung spacings of 6, 9, 12 or 18 inches. Note that wider rung spacings and wider cable tray widths decrease the overall strength of the cable tray. Specifiers should be aware that some cable tray. The spacing between trays, whether horizontal or vertical, depends on various factors like cable type, environment, and tray material. Proper installation can significantly reduce electromagnetic interference, prevent fire hazards, and improve overall efficiency. 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. us-trations without notice. 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.