Standard for connecting hollow cable trays

Hollow cable trays are typically connected using manufacturer-supplied joining pieces, bolts, and nuts, following standards such as NEMA VE 2-2018 and DIN EN 61537.

Joining Methods

Hollow cable trays are joined using couplers or connectors supplied by the tray manufacturer. Each tray section is equipped with flanged edges to ensure rigidity and minimize damage to cable sheaths during handling. Standard joining procedures include:

• Bolts and nuts: Stainless steel bolts and nuts are used to secure adjacent tray sections, often with spring washers to maintain tension and prevent loosening under vibration or thermal expansion .
• Couplers/connectors: For bends, tees, or crossovers, specialized connectors are used to maintain alignment and structural integrity .
• End fittings: End closures or caps may be applied to prevent cable damage and provide a finished appearance .

Material and Hardware Standards

• Stainless steel: Mounting channels, bolts, nuts, and anchor bolts should comply with BS EN 10088-2 Grade 1.4401 (ASTM 316) for corrosion resistance .
• Flanged edges: Tray sides are typically 180° return flanged to enhance rigidity and protect cables .
• Slot engagement: Nuts with slots engage with channel lips to ensure secure fastening .

Support and Spacing

• Support spacing: Recommended support spacing depends on tray width and load but should follow manufacturer guidelines and standards like NEMA VE 2-2018 .
• Mounting channels: Channels are usually 40mm x 40mm with a minimum thickness of 2.5mm, providing adequate structural support .

Standards Reference

• NEMA VE 2-2018: Provides guidelines for cable tray design, joining, and installation, emphasizing safety, mechanical load capacity, and corrosion resistance .
• DIN EN 61537: Defines cable support systems, including trays, ladders, and mesh trays, and specifies fittings, support elements, and accessories for secure cable routing .
• Local specifications: For example, STANDARD SPECIFICATION E-30-11 details tray lengths, perforation sizes, and recommended joining hardware . By following these standards and using manufacturer-supplied connectors and hardware, hollow cable trays can be safely and reliably connected, ensuring both mechanical stability and compliance with electrical installation requirements.