How to level tunnel cable tray supports

Leveling tunnel cable tray supports requires careful alignment, proper support spacing, and the use of leveling tools to ensure a safe, stable, and code-compliant installation.Key Steps for Leveling Cable Tray Supports in Tunnels1. Plan the Layout and Support Points Before installation, determine the cable tray route, considering tunnel geometry, bends, and downward or upward runs. Identify support points along the tray according to the manufacturer's recommended span limits and load requirements, ensuring the system can handle the weight of cables and any future additions (BEAMA guide) . 2. Select Appropriate Support Types Use suitable support elements such as wall brackets, suspended supports, or center suspensions depending on the tunnel structure (concrete walls, beams, or ceilings). Supports must be compatible with the tray type (ladder, perforated, or GRP) and designed to maintain alignment under load (OBO CMS guide) . 3. Use Leveling Tools Employ a spirit level, laser level, or optical level to ensure horizontal alignment of each support. For long tunnel runs, a laser level is preferred for maintaining consistent elevation over distance. Adjust each support individually before securing it to the tunnel structure. 4. Install Supports and Tray Sections Attach supports securely to the tunnel structure, checking that each is level. Begin installing tray sections from one end, connecting them to the supports. Use shims or adjustable brackets if minor height corrections are needed to maintain a continuous level line (Legrand tunnel guide) . 5. Check Alignment Continuously After installing each section, verify that the tray remains level and straight. Ensure that bends, T-pieces, or crossovers are aligned with the main run. Minor adjustments can be made using the support brackets before tightening all fasteners. 6. Consider Load and Deflection Ensure that the installed tray does not exceed deflection limits specified by the manufacturer. Supports should be spaced to prevent sagging, especially in long horizontal runs or when carrying heavy cables (EEP guide) . 7. Final Inspection Once the tray is fully installed, perform a final check with a level along the entire run. Confirm that all supports are secure, the tray is level, and there are no gaps or misalignments that could compromise cable safety or future maintenance.Additional TipsFor tunnels with curved walls or ceilings, use custom support brackets or adjustable hangers to maintain level alignment.Use corrosion-resistant materials (stainless steel or GRP) in humid or underground environments to ensure long-term stability.Follow relevant standards such as BS EN 61537 for cable trays and BS 6946 for channel support systems to ensure compliance and safety . By following these steps, tunnel cable tray supports can be installed level, secure, and compliant, ensuring safe cable routing and long-term reliability.