The cable trays are connected by a wire

Cable trays are typically connected using mechanical fittings like splice plates, but a wire can be used for grounding or bonding to ensure electrical continuity.

Mechanical Connection of Cable Trays

Cable trays are modular systems composed of straight sections, bends, tees, and other fittings that form a continuous pathway for cables . To join two sections of a tray, splice plates or connector brackets are commonly used. These plates are bolted across the ends of adjacent trays to provide a secure, rigid connection, maintaining alignment and structural integrity . Ladder, channel, and wire mesh trays all use similar methods, though the exact hardware may vary depending on the tray type .

Electrical Bonding with a Wire

While mechanical connections hold the trays together, a wire is often used to bond or ground the trays. This ensures that all sections of the tray system are electrically continuous, which is critical for safety and compliance with electrical codes . The bonding wire is typically connected to the tray at multiple points using clamps or lugs, linking the tray to the building's grounding system. This prevents potential electrical hazards from stray currents or lightning strikes.

Additional Considerations

• Tray Type: Wire mesh trays (basket trays) are lightweight and flexible, making them easier to bond with a wire, while ladder trays may require additional grounding points due to their larger metal structure .
• Supports and Fittings: Trapeze hangers, wall brackets, and other supports maintain tray alignment and can also serve as grounding points if properly bonded .
• Covers and Accessories: Covers, hold-down clamps, and drop-outs do not typically affect bonding but should be installed according to manufacturer guidelines to maintain safety and accessibility . In summary, cable trays are connected mechanically with splice plates or fittings, and a wire is used to bond the trays electrically, ensuring both structural stability and safety for the cable system .