How to connect cables exiting the cable tray

Cables exiting a cable tray should be routed through a raceway with a bushing or through a flanged opening on equipment, with proper sealing to prevent debris and ensure safety.

Transition Methods

1. Bushed Conduit or Tubing Cables can exit the tray and enter equipment through a raceway fitted with a bushing. The bushing protects the cable insulation from abrasion and mechanical damage at the entry point. This method is compliant with NEC 392.46 and is suitable for both protection and support of conductors .
2. Flanged Equipment Openings Alternatively, cables can enter equipment through a flanged opening on top of the enclosure. The flange should be smooth or fitted with a protective grommet to prevent cable damage. Both methods now require sealing the opening with duct seal or similar material to prevent debris from entering the equipment .

Best Practices

• Secure and Organize Cables: Use cable ties or straps to bundle and separate cables by voltage or function, leaving enough slack for movement and future adjustments .
• Protect Against Abrasion: Ensure all edges at the tray exit are smooth or protected with bushings or grommets to prevent insulation damage .
• Maintain Grounding and Bonding: Metal trays should be properly grounded, and bonding jumpers should maintain electrical continuity across tray sections .
• Label and Document: Clearly label cables and maintain updated wiring maps for troubleshooting and maintenance .
• Follow Manufacturer Guidelines: Use compatible fittings, splice plates, or clamps recommended by the tray manufacturer to ensure secure connections and system stability .

Additional Considerations

• Mechanical Protection: Cable trays are designed to support cables but not to provide full mechanical protection. Ensure cables are not subjected to excessive bending or weight at the exit point .
• Code Compliance: Always follow NEC requirements and local electrical codes for cable tray transitions, including proper sealing and protection measures .
• Inspection and Maintenance: Regularly inspect tray exits for loose cables, damaged insulation, or unsealed openings to maintain safety and reliability . By following these methods and best practices, cables exiting a cable tray can be safely routed to equipment while minimizing the risk of damage, maintaining system integrity, and ensuring compliance with electrical standards.