This guide covers the cable tray types and their appropriate applications, the fill rules for each configuration, ampacity derating requirements, separation of power and signal cables, and the decision criteria for choosing cable tray over conduit. Cable tray is the preferred wiring method for industrial facilities, data centers, and large commercial buildings where routing dozens or. association representing the major electrical equipment manufac-turers in the U. 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. Ethernet cables supporting PoE lighting, IP cameras, and office network infrastructure must meet the appropriate fire and performance ratings, such as CMR (riser-rated), CMP (plenum-rated), or tray-rated, where applicable. When properly selected and installed, cable trays simplify routing, improve accessibility, and support future expansion while. us-trations without notice. All illustrations, descriptions and technical information included in this document are provided as indications and can cable trays are equivalent.