Cost-Effective: Making hollow trays uses less material. This can make them a more affordable option compared to solid or steel-lined types. more Find out how you can install cable trays faster and easier with our innovative patented product Hermi® Fast Joint. In the video, you will be able to see a comparison between. en completely installed, without damage either to conductors or structural system use maintain spacing or to keep cables in place when the tray is ect the minimum bend ra-dius for cables as they exit the bottom of the cable tray. Cable tray installation implies the construction of an electric road that will be safe.