Cable tray systems are structural components used to support insulated conductors and control, instrumentation, and communication cables. They are typically installed overhead, along walls, or under raised floors in electrical rooms, industrial plants, process areas, and. 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. Unlike power cables, instrumentation cables generally transmit. 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. An effective layout ensures safety, minimizes interference, reduces maintenance time, and keeps the overall. Q1: What is the primary purpose of cable tray sizing and calculation? Ensure the total cable area does not exceed the maximum fill area permitted by electrical codes (e. Prevent cable damage during installation and maintenance due to overcrowding. Provide adequate air circulation. The Cable Tray Institute (CTI) was founded in 1991 to support the cable tray industry by engaging in research, development, education, and the dissemination of information designed to promote, enhance, and increase the visibility of the industry. Cable tray, introduced in the mid 1940s, is a safe.