Cable tray instrument wiring
The National Electrical Code (NEC), specifically Article 392 (Cable Trays), provides strict rules on cable fill area, maximum cable sizes, and acceptable loading depending on the type of conductor (single or multi) and the type of tray (ladder, ventilated trough, solid. In instrumentation EPC (Engineering, Procurement, and Construction) projects, installing cable trays is very important for making sure that signals are sent reliably, that people are safe, and that systems work well for a long time. Generally instrument cabling is usually run in multicore cables from the control room to the plant area (either below or above the ground) and then from field junction boxes in single pairs to the field measurement or actuating devices. 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. 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.
Read More