Cable tray installation errors can lead to misalignment, reduced functionality, and even safety hazards. The Cable Tray ng standards, performance standards, test standards and application in this document have been tested extens ompetent professional en completely installed, without damage either to conductors or. A cable tray is a structural system used to organize and protect electrical cables in industrial, commercial, and residential setups. It is a safe way to route cables for easy maintenance and future upgrades. Cable sag results from incorrect spacing of cable tray supports or from employing the incorrect tray type that is, light-duty perforated trays in high-load applications. Let's analyze the most frequent mistakes.