Cable tray climbing bends should be designed and installed according to IEC 61537 and BS EN 61537 standards, ensuring proper bend angles, support, and minimum bend radius for safe cable routing.

Standards and Guidelines

Cable tray climbing bends are vertical or inclined sections that allow cables to transition between different elevations. Their design must comply with IEC 61537 and BS EN 61537, which specify construction, mechanical strength, and compatibility requirements for cable trays and accessories . These standards ensure that the bends can safely support the weight of cables, maintain electrical continuity, and prevent damage during installation or operation.

Bend Angles and Radius

• Typical climbing bend angles are commonly 30°, 45°, 60°, or 90°, depending on the installation requirements and available space .
• Minimum bend radius is critical to prevent cable damage. The radius should generally be at least 6–10 times the cable diameter for power cables, though specific values depend on cable type and manufacturer recommendations .
• Smooth bends are preferred to reduce stress on cables and maintain signal integrity for sensitive instrumentation or control cables.

Installation Considerations

• Support spacing: Climbing bends should be supported at intervals similar to straight tray sections, typically 1.5–2 meters, to prevent sagging and maintain structural integrity .
• Material selection: Bends should match the tray material (steel, aluminum, or stainless steel) to ensure mechanical compatibility and corrosion resistance .
• Electrical continuity: When cable trays serve as grounding paths, climbing bends must maintain low-resistance connections across joints, typically less than 0.1 ohms .
• Ventilation and heat dissipation: For power cables, ventilated or perforated bends are recommended to prevent overheating, especially in long vertical runs .

Practical Tips

• Use prefabricated bends whenever possible to ensure compliance with standards and reduce installation errors.
• Avoid sharp or abrupt bends that exceed the recommended angle or radius, as this can damage insulation or reduce cable lifespan.
• For multiple cable layers, ensure that the bend design accommodates the total cable fill without exceeding tray load limits . By following these guidelines, climbing bends in cable tray systems can provide safe, efficient, and code-compliant vertical cable routing in industrial, commercial, and utility installations.