Laying of ladder-type cable trays

Ladder-type cable trays should be installed on properly spaced supports, aligned horizontally and vertically, with cables neatly laid and secured to ensure safety, accessibility, and compliance with standards.

Preparation and Material Handling

Before installation, all cable trays, ladders, and accessories must be inspected for damage and verified against approved material submittals. Materials should be stored horizontally on a flat surface with timber supports at intervals of about one meter, protected from moisture and sunlight. Review the approved shop drawings to determine tray routes, lengths, and locations, ensuring coordination with other services and maintaining adequate clearance for cable pulling and future maintenance.

Support and MountingLadder-type trays require strong supports capable of handling the cable load and any future additions. Supports are typically spaced between 1. 5 to 3 meters depending on tray type and load.

Supports should be installed to maintain horizontal and vertical alignment, avoiding sagging or deflection beyond manufacturer limits. Avoid cutting or drilling structural members without approval. Use appropriate brackets, clamps, and hangers to secure the trays firmly to walls, ceilings, or floors.

Tray Alignment and Connection

Align trays straight and level, connecting sections using manufacturer-approved fittings. For long runs, cable tray rollers can be used to facilitate smooth cable laying and prevent kinks. Ensure that joints are properly bonded and grounded to maintain electrical continuity and safety.

Cable Laying

Cables should be laid neatly within the ladder rungs, organized by voltage and function, and secured with cable ties or straps. Leave sufficient slack for thermal expansion, movement, or future adjustments. Ladder-type trays allow airflow around cables, reducing heat buildup and facilitating maintenance.

Inspection and Documentation

After installation, perform a thorough inspection to check for loose clamps, misalignment, overfilled sections, or unsupported spans. Ensure compliance with safety codes and site-specific regulations. Label cables clearly and maintain updated documentation for future reference and audits.

Safety Considerations

Only trained and competent personnel should perform installation. Ladder-type trays are designed to support cables, not personnel. Follow all safety induction procedures, and do not proceed under unsafe conditions.

Proper grounding, bonding, and adherence to manufacturer specifications are essential for safe and reliable operation. By following these steps, ladder-type cable trays can be installed efficiently, safely, and in a manner that allows for easy maintenance and future expansion.