Support spacing for cable trays must align with the manufacturer's instructions, as outlined in NEC 392. Generally, standard trays require supports every 6 to 10 feet, while heavy-duty, long-span trays can handle distances of up to 20 feet between supports. Specifiers should be aware that some cable tray. Understanding cable tray spacing is key to meeting safety regulations and maintaining system performance. The spacing between trays, whether horizontal or vertical, depends on various factors like cable type, environment, and tray material. The Ladder Tray features light, rugged, tubular steel construction. 50 in the development and approval of the document at the time it was developed.