All tray items whether stored outside or indoors, should be placed on sufficient dunnage to enable future mechanical lifting. Important considerations in any cable installation are ambient temperature, equipment used, conduit or tray fill, friction forces, mechanical layout of a raceway and physical limitations of the cable. This document is not intended to be an all. This guide covers the critical steps, from selecting the right electrical cable tray and performing accurate cable fill calculations to managing a safe cable pull through and ensuring all bonding and grounding requirements are met. A rung spacing of 6 to 9 inches (150 to 230 mm) is preferable when. Working with cable trays is not just a routine installation job. If a tray is overloaded, corroded, poorly supported, or contains live cables, it can create severe risks for workers and equipment.
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