Cable Management Tray Size: Choose a tray size that will hold the desired amount and length of cable. Support Spacing: Remember the NEC requires no more than 4 feet of support spacing. Bend Radius: The tray cable bend radius should be supported to avoid. 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. It also demonstrates how Eaton's solutions and services can help: As an industry leader in cable tray, Eaton offers one of the widest ranges of. Although BS 7671 touches on the subject of cable supports, it does not detail specifically what these support distances should be. Route. It ensures that cable trays are compatible with various fittings, bends, risers, and other accessories for a seamless installation.