Spacing Standards: Electrical (power) and instrumentation (signal/control) cable trays should maintain a minimum vertical and horizontal distance. The distance between trays affects not only the ease of maintenance but also cable protection, heat dissipation, and system stability. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned. in this document have been tested extens ompetent professional 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. The Cable Tray system is installed in electrical rooms, plant rooms, and service corridors. This section will guide you through the necessary steps to ensure a successful. 1.