Connection of ladder-type and trough-type cable trays

Ladder-type and trough-type cable trays can be connected using compatible fittings, splice plates, and reducers while ensuring proper support, alignment, and grounding.

Overview of Cable Tray Types

Ladder-type trays feature two side rails connected by rungs, providing excellent ventilation and support for heavy cables over long spans, while trough-type trays have solid or perforated sides and a continuous base, offering more protection for cables from dust and debris . Both systems are designed to support cables but differ in structure and load distribution.

Connection Methods

1. Use of Splice Plates and Reducers
   • Splice plates are commonly used to join straight sections of different tray types securely .
   • Reducers allow transitions between trays of different widths or types, ensuring a smooth cable path from ladder to trough .
2. Alignment and Support
   • Ensure both trays are aligned horizontally and vertically to prevent cable strain .
   • Maintain proper support spacing: ladder trays typically require supports every 1.2 meters, and trough trays may have similar or slightly shorter spans depending on load .
   • Use compatible hangers, brackets, or trapeze supports to anchor both tray types to the building structure.
3. Mechanical and Electrical Considerations
   • Secure connections with bolts or clamps designed for the specific tray system to maintain structural integrity .
   • Ensure grounding continuity across the connection, especially when combining metallic ladder and trough trays, to comply with electrical safety standards .
4. Fittings for Direction Changes
   • Horizontal and vertical bends, tees, and offsets can be used to transition between tray types while maintaining cable routing .
   • Avoid sharp bends that could damage cables or reduce pulling efficiency.

Best Practices

• Always follow manufacturer guidelines for connecting different tray types, as some systems may require proprietary adapters .
• Inspect all materials for damage before installation and verify that splice plates, reducers, and fasteners are compatible with both tray types .
• Maintain adequate clearance for cable pulling and future maintenance, especially at the junction of ladder and trough trays .
• Ensure the combined system meets relevant standards such as BS EN 61537 for cable tray systems . By carefully planning the transition, using appropriate fittings, and maintaining proper support and grounding, ladder-type and trough-type cable trays can be integrated into a single, safe, and efficient cable management system.