Spacing Standards: Electrical (power) and instrumentation (signal/control) cable trays should maintain a minimum vertical and horizontal distance. The spacing between trays, whether horizontal or vertical, depends on various factors like cable type, environment, and tray material. For proper installation, design, and maintenance, adherence to international standards is essential. One of the most recognized frameworks globally is the IEC standard for. us-trations without notice. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned. 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. Clause 522-08-04 Where conductors or cables are not supported.