Laying out the 800-degree bend in the cable tray

An 800-degree bend in a cable tray requires careful planning using multiple standard bend fittings, maintaining proper bend radius, and ensuring compliance with NEMA and IEC standards.Planning the BendWhen laying out an 800-degree bend, the total bend is typically achieved by combining multiple standard bends (e.g., 90°, 45°, or 30° elbows) rather than attempting a single extreme curve. This approach ensures:Cable integrity: Avoids excessive stress or kinking of cables.Ease of installation: Standard fittings are easier to handle and secure.Compliance: Meets NEMA VE2 and IEC 61537 guidelines for mechanical strength and cable support .Steps for InstallationReview Shop Drawings: Confirm the exact routing, bend locations, and clearance requirements. Ensure the 800-degree path does not interfere with other services .Select Fittings: Use a combination of standard bends (e.g., 90° and 45° elbows) to achieve the total 800° turn. Ensure the bend radius meets the minimum recommended for the cable type to prevent damage .Mark the Route: On-site, mark the tray path and bend points according to the approved layout. Maintain horizontal and vertical alignment for proper support .Install Supports: Place hangers or brackets at intervals recommended by the manufacturer, typically every 1.5–3 meters for ladder trays, to support the weight of the cables and fittings .Assemble the Bend: Connect the bend fittings sequentially, ensuring each joint is properly fastened and aligned. Check that the cumulative angle equals 800°.Verify Clearance: Ensure sufficient space for cable pulling and future maintenance. Maintain separation from other services and avoid sharp edges .Secure and Ground: Fasten the tray and fittings securely. For metallic trays, ensure electrical continuity and grounding according to IEC 61537 .Additional ConsiderationsCable Stress: Avoid tight bends that exceed the cable manufacturer's minimum bend radius.Material Choice: Steel, aluminum, or fiberglass trays may have different bend tolerances; select fittings compatible with the tray material .Inspection: After installation, inspect the bend for alignment, support, and compliance with standards before cable pulling . By following these steps and using multiple standard fittings, an 800-degree bend can be safely and efficiently installed while maintaining cable integrity and compliance with industry standards.