Are there any connections in galvanized cable trays

Yes, galvanized cable trays should be mechanically connected for stability and may require grounding or bonding depending on their use and local electrical codes.

Mechanical Connection

Galvanized cable trays must be physically connected to ensure system stability, support the weight of cables, and prevent sagging or misalignment. Proper connections improve durability, facilitate maintenance, and comply with building and electrical codes. Common connection methods include splice plates, bolted connections, clamps, and quick-connect systems, which secure tray sections in straight runs or at junctions, maintaining structural integrity and load-bearing capacity .

Electrical Grounding and Bonding

Even if galvanized, metallic cable trays are considered exposed conductive parts and may need to be grounded. According to NEC Article 250.96, all metallic trays must be grounded regardless of whether they serve as an equipment grounding conductor (EGC). The tray itself can sometimes act as the EGC if its cross-section and continuity meet code requirements, but installing a separate EGC conductor bonded to each or alternate tray section is a recommended practice for safety .

• Bonding clamps are used to electrically connect tray sections and anchor the EGC, preventing it from being displaced under fault currents .
• Insulated conductors are preferred in aluminum or mixed-metal installations to avoid electrolytic corrosion, but galvanized steel is generally compatible with bare copper grounding .
• For functional reasons like static discharge or RFI, trays may be earthed at one end only to avoid loops that could cause nuisance trips .

Galvanization Considerations

Galvanization provides corrosion resistance and mechanical strength, but it does not eliminate the need for proper connections or grounding. The zinc coating protects the steel from corrosion, but electrical continuity across tray sections must still be ensured for safety and code compliance .

Summary

• Mechanical connection: Required for stability, load support, and maintenance.
• Electrical connection/grounding: Required if the tray is exposed conductive or used as an EGC; bonding is recommended for safety.
• Galvanization: Protects against corrosion but does not replace mechanical or electrical connections. Proper installation ensures both structural integrity and electrical safety, making connected and grounded galvanized cable trays essential in most electrical systems .