• Cables may exit or enter through the top or the bottom of the tray. 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. Cable ladder systems and cable tray systems shall be manufactured in accordance with BS EN 61537, channel support. Although BS 7671 touches on the subject of cable supports, it does not detail specifically what these support distances should be. 8 (Other Mechanical Stresses (AJ)) in that document provides requirements for cable support. Clause 522-08-04 Where conductors or cables are not supported. These rules have to be respected scrupulously by the engineering services, consulting firms, the fitters (external companies, employees of the technical services or employees of the maintenance services, the laboratory agents) implementing or working on cabling systems in the ITER facility during. • Cables may exit or enter through the top or the bottom of the 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.