They must be used at various key points of the tray system: at the beginning and end of the tray, at corners, T-junctions, and when the tray spans a length greater than 30 meters. Cable supports should be applied at either side of the bend. Where long vertical runs are used (e. There are various ways of including strain relief sections, but the preferred method is to offset the cable by at least 2 cable. A common application is the use of longer brackets when pipes, thermal insulation, wall projections or recesses, or other technical installations cross the direct route of the cable tray. The test certificates define cable trays and brackets with the same nominal width or length, for example, a 400. Selecting a cable tray length is based on several criteria, including: The required load that the cable tray must support. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned in this technical guide only apply to our own cable management ranges and cannot under any circumstances be transposed to si osure, overheating or. Cable trays play a vital role in supporting electrical cables and wires in commercial, industrial, and utility installations. The significance of this difference is that it varies the type of wires that can be employed.