Various bends and right angles in cable trays

Right-angle bends are allowed in cable trays, but they must be implemented using proper fittings to avoid damaging cables and to maintain compliance with standards.

Use of Bends in Cable Trays

Cable trays are designed to support and route electrical cables while allowing changes in direction. Direct 90-degree bends in the tray itself without fittings are not recommended, as sharp bends can stress cables, reduce their lifespan, and violate minimum bend radius requirements for certain cable types . Instead, elbows or pre-fabricated bend fittings are used to achieve right-angle turns safely.

Standards and Guidelines

According to DIN EN 61537, cable support systems, including trays, allow the use of fittings for horizontal or vertical changes in routing direction, such as bends, T-pieces, and crossovers . These fittings ensure that cables are not subjected to excessive bending stress and maintain proper spacing. The minimum bend radius for cables must always be respected, which depends on the cable type and insulation, to prevent insulation damage or conductor deformation .

Practical Considerations

• Horizontal bends: Use elbow fittings to guide cables smoothly around corners.
• Vertical bends: Use vertical elbows or riser fittings to change elevation without sharp kinks.
• Cable spacing: Maintain adequate spacing within the tray to prevent overcrowding at bends.
• Support: Ensure bends are supported with brackets or hangers to prevent sagging or mechanical stress .

Summary

Right-angle bends are permissible in cable tray systems when implemented with the correct fittings and by following standards like DIN EN 61537. Avoid forcing cables into sharp corners without fittings, as this can compromise cable integrity and safety. Proper planning of bends, spacing, and support ensures both compliance and long-term reliability of the cable installation .