Page 15 - IEC Insights Nov-Dec21_WEB

The standard finish is electro-plated zinc galvanized which is most suitable for indoor
applications or outdoor environments with mild conditions. With special order finishes, wire
basket trays are suitable for outdoor applications where corrosion resistance is required.

Designing for Custom Uses
A full range of accessories make a cable tray system completely customizable. For
complex configurations, fittings are used to change the size or direction of the cable tray.
Horizontal or vertical bends are offered for each tray width and with angles of 30°, 45°,
60° or 90°. The radius of the bend, whether horizontal or vertical, can be 12", 24", 36"
or greater on a custom basis. Determining the radius comes down to available space,
minimum bending radius of the cables, the ease of cable pulling and cost. The most
common radius is 24", but when a standard angle will not work, field fittings or adjustable
elbows can be used.

Designing for Strength
If the application demands double the pull-out strength, stiffer rigidity, and unobscured
access to cables, a swaged rung cable ladder tray system could be right for the task.

In the swaging manufacturing process, a machine compresses and locks the tubular rung
of a ladder tray around both the inside and outside of the side rails. The connection is
made without the use of heat which can potentially disturb the molecular structure of
the metal, weaken it, and disrupt its electrical grounding properties. The tubular rung is
flattened during the swaging process to ensure a proper cable bearing surface. This type
of process can allow pullout loads of 2,500 pounds and can maintain the 90° relationship
of the rungs to the side rail. Cold swaging allows for the side rails to be turned completely
outward, simplifying the cable installation and providing full access to the cables.
Ladder tray systems allow for easy cable installation as well as future access for adding
or removing cable runs, making it a cost-effective alternative.

Conclusion

The efficiency and life expectancy of any installation depends largely on the system
selected. Choosing the proper system for the application takes careful understanding
of all aspects of the installation to choose the right cable tray for the job. But once that
preparation is done, the system can grow and expand with business needs. Ultimately,
the engineer or designer should select a cable tray system that suits the project’s
requirements and adheres to NEC and NEMA standards. Cable tray manufacturers,
such as Cope, provide free engineering consultation services to assist in selecting and
designing the optimal cable tray solution.

Eric Gertie is Product Manager for Atkore’s Cable Management Business Unit.