Low-voltage cables do not need to be run through cable trays

It is not strictly mandatory to run low-voltage cables in cable trays, but using trays is strongly recommended for safety, organization, and compliance with NEC standards.

Regulatory and Safety Considerations

The National Electrical Code (NEC) Article 392 governs cable tray installations, specifying which cables are permitted, how they should be supported, and separation requirements between power and low-voltage circuits . While low-voltage cables (such as Ethernet, control, or signaling cables) do not always require a tray, using one ensures proper support, reduces mechanical damage, and maintains separation from high-voltage power cables to prevent interference .

Separation and Interference

Low-voltage cables should be physically separated from high-voltage power cables to avoid cross-talk, signal distortion, or electrical interference . NEC and industry best practices recommend either separate trays, conduits, or divider systems when routing mixed-voltage circuits. Shielding alone does not replace the need for proper separation .

Practical Installation Considerations

• Cable support: Even if not in a tray, low-voltage cables must be supported and secured to prevent sagging or damage. Tie-downs or barriers may be required in horizontal or vertical runs .
• Accessibility: Cable trays provide easy access for installation, maintenance, and future upgrades, which is especially important in data centers or industrial facilities .
• Protection: Trays protect cables from physical damage, environmental exposure, and excessive heat, particularly for tray-rated or plenum-rated cables .

When Trays May Not Be Required

In some installations, low-voltage cables can be run in conduits, raceways, or along walls/ceilings if they are properly supported, separated from power circuits, and meet NEC requirements for cable type and fire rating . However, skipping trays may complicate maintenance and increase the risk of interference or mechanical damage.

Conclusion

While low-voltage cables do not always have to be installed in cable trays, using trays is considered best practice for safety, compliance, and long-term reliability. If trays are not used, ensure proper support, separation from high-voltage circuits, and adherence to NEC standards for cable type, spacing, and accessibility .