The width of a channel tray is a function of the number, size, spacing and weight of the cables in the tray. Available nominal widths are 1. When specifying width, cable ties or other spacing devices may be used to maintain the required. In practice, cable tray dimensions are a system of interrelated measurements —width, depth, length, and material thickness—that directly affect cable fill compliance, heat dissipation, structural loading, and long-term expandability. The information has been organized for. gth of the ASTM standards (ASTM A 653) with G 90 coating thickness. are to be constructed of AiSi type 304 or type 316 s All trays to be labe o be fabricated from continuous roll-formed structural.