Secure to Supports: Use hold-down clips or bolts to fasten the tray to the brackets or strut channel so they don't slide. Use splice plates (couplers) on the sides to connect them. Whether you're building a commercial setup or upgrading an industrial plant, proper cable tray installation ensures neat wiring, safe access, and easy maintenance. Check Regulations: Consult the National Electrical. When offloading tray from a flat deck trailer using an overhead crane, care should be exercised in the placement and length of the slings to prevent crushing the product (siderails). A rung spacing of 6 to 9 inches (150 to 230 mm) is preferable when. We recognize the need for a complete cable tray reference source for electrical engineers and designers.