Cable Types: Only use conductors rated for open-air environments, such as Tray Rated (Type TC) or Metal-Clad (Type MC) cables. Clearances: Maintain at least 12 inches of vertical clearance above trays for installation and maintenance access (2026 NEC update). The metal in cable trays may be used as the EGC as per the limitations. The B-Line series Cable Tray Manual was produced by our technical staff. The following pages address the 2014 National Electrical Code® requirements for cable tray systems as well as design. 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. A rung spacing of 6 to 9 inches (150 to 230 mm) is preferable when. 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. 16, tray fill, ampacity adjustment, voltage-drop checks, grounding, and IEC design cross-checks. Use NEC 392 for tray rules, but still size conductors from NEC 310. Tray fill, spacing, ambient temperature, and sun exposure. Cable tray (or cable ladder) systems are a popular alternative to electrical conduit systems, as they have an outstanding record for dependable service, design flexibility and cost savings in commercial and industrial applications. A properly designed and installed cable tray system will provide.
