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. 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. 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. Knowing these details can help you stay compliant and avoid costly errors. Clause 522-08-04 Where conductors or cables are not supported.
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