National Electrical Code Section392. 8 (B) states that in other than horizontal cable tray runs, the cables shall be fastened securely to transverse members of the cable trays. The cable's. This work is licensed under the Creative Commons Attribution-Noncommercial-NoDerivs 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. Cable tray types, fill rules for single-conductor and multiconductor cables, ampacity derating, separation requirements, and when to use tray vs conduit. Cable Tray Types and When to Use Each 2. Ampacity Derating. Through NEMA and the Cable Tray Institute numerous articles, standards, and other general guidance can be found regarding the proper use and installation of cable tray systems. A rung spacing of 6 to 9 inches (150 to 230 mm) is preferable when the cable tray cont d for instrumentation and control applications that require. Below are the key principles to guide the layout of E&I cable trays, focusing on practical, safety, and efficiency aspects. Separation of Electrical and Instrumentation Cables Electrical on Top, Instrumentation Below: Typically, electrical trays are positioned above instrumentation trays. The respective article for the cable type must also be followed.
