31 (C) now aligns with the Code's broader language (like Article 392), allowing these smaller conductors and detailing how to calculate ampacities, the number of conductors permissible in cable trays, how to size cable trays correctly by width, layering. The updated section 690. 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. Article Summary: A compliant cable tray installation requires a thorough understanding of NEC Article 392, proper structural support, and precise installation techniques. This method statement covers the site installation of the cable tray & ladders and the requirements of checks to be carried out. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned in this technical guide only apply to our own cable management ranges and cannot under any circumstances be transpos regulations which. This work is licensed under the Creative Commons Attribution-Noncommercial-NoDerivs 3. 0 IGO-ported license (CC BY-NC-ND 3. You are free to share this work (copy, distribute and transmit) under the following conditions: you must give credit to the ITER Organization, you cannot use the work.