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High-voltage cable trays are turning red
This guide discusses common cable tray problems, from loosening and corrosion to grounding issues and installation errors, along with strategies for prevention and resolution. These cable trays require the DANGER marking. Code Change Summary: A clarification was made regarding marking of cable trays containing conductors operating over 600 volts. 18 (H) is clear on the requirements for properly marking cable tray to ensure that everyone knows the potential danger of high voltage cables: (H) Marking Cable trays containing conductors operating over 600 volts shall have a permanent, legible warning notice carrying the wording. Warning signs or brightly colored spherical markers, sometimes red or orange, are affixed to the lines near airports or across valleys to make the conductors visible to aircraft, but these are not insulation colors. However, these trays are not immune to safety hazards that could cause system failures, fires, or other catastrophic events.
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Cable trays and other turning points
Several types of tray are used in different applications. A solid-bottom tray provides the maximum protection to cables, but requires cutting the tray or using fittings to enter or exit cables. A deep, solid enclosure for cables is called a cable channel or cable trough. A ventilated tray has openings in the bottom of the tray, allowing some air circulation around the cables, water drainage, and allowing some dust to fall through the tray. Small cables may exit the tray throug.