PW LADDER TRAY PW LADDER TRAY Understanding Our Products LOAD DEPTH: Interior depth of the cable tray that is available for cable fill. Specifications for cable trays should include a specific requirement for the tray load depth. Due to design variations between different manufacturers, it is important to specify an exact load depth to ensure equal performance. The load depth may differ slightly based on choice of tray bottom. TRAY OPTIONS It is essential to consider the type and quantity of cables to be installed in the cable tray when planning your project. Refer to Article 392 of the National Electrical Code (NEC) for guidelines on calculating the cable tray depth and width. WIDTH: Interior width of the tray or channel that is available for cable fill. LOAD/SPAN CLASS DESIGNATION THE LOAD/SPAN CLASSIFICATION describes the cable tray's load-carrying capability for a specific support span. A classification should be selected that reflects the actual working load and support span for each application. This designation directly affects the cost of the tray, so the proper selection is essential to determine the most economical cable tray system necessary for each project. Please consult with Legrand for working loads and support spans that fall outside the boundaries of the Load/Span Classes shown. CONCENTRATED STATIC LOAD: In addition to an evenly distributed INTRODUCTION cable load, it is occasionally required that the cable tray system be capable of supporting a concentrated static load. A concentrated static load represents a static weight applied on the centerline of the cable tray at midspan. The concentrated static load in lbs. may be converted to an equivalent uniform load (We) in lbs./ft., using the following formula, and added to the static weight of cables in the tray. A NEMA Load Class can then be selected that reflects the combination of the cable load and converted static load. B.4 WWW.LEGRAND.US/CABLOFILhttp://WWW.LEGRAND.US/CABLOFIL