Converting a cable tray tee to a parallel configuration involves using branch fittings or on-site modifications to split the main tray into parallel runs while maintaining mechanical and electrical integrity.

Understanding Tee vs Parallel Configuration

A tee fitting in a cable tray system has three connectors: one for the main run and two for the branch, forming a T-shaped junction. In contrast, a parallel configuration involves running two or more trays side by side to distribute cables evenly, often to increase capacity or separate circuits for safety and cooling purposes .

Methods for Conversion

1. Using Branch Fittings
   • Some manufacturers provide branch pieces that allow a single main tray to feed into a parallel tray without a full tee.
   • These branch pieces typically have one connector and require cutting or modifying the main tray on-site to fit the branch properly .
   • This method is faster and can reduce the number of fittings needed, but care must be taken to maintain structural support and proper alignment.
2. On-Site Tee Modification
   • If a standard tee is used, the main tray may need to be chopped or trimmed to allow the parallel tray to align correctly .
   • Ensure that the edges are smooth and reinforced to prevent cable damage and maintain mechanical strength.
3. Parallel Conductor Considerations
   • When running parallel conductors in the trays, ensure adequate spacing for cooling and ampacity compliance.
   • Single-core cables are preferred for large fault current systems, and they should be properly cleated rather than zip-tied to withstand electrodynamic forces .
   • Maintain proper grounding and separation of circuits to avoid interference and ensure safety.

Installation Tips

• Use universal splices or clamps to secure parallel trays together, ensuring alignment and stability .
• Verify that the tray width and load class are sufficient for the combined cable weight .
• Always follow manufacturer guidelines and local electrical codes for modifications and parallel installations .

Summary

Converting a tee to a parallel configuration is feasible using branch fittings or on-site modifications. Key considerations include mechanical support, electrical safety, proper spacing, and compliance with standards. Proper planning and adherence to manufacturer instructions ensure a safe and efficient parallel cable tray system.