Cable tray trough type cable tray

A cable trough, also known as a ventilated trough cable tray, is a type of cable tray with a solid bottom featuring ventilation holes, providing continuous cable support while allowing limited airflow.

Overview

Cable troughs are designed to support and protect insulated electrical cables in industrial and commercial installations. Unlike ladder trays, which have open rungs, cable troughs have a solid bottom with perforations, offering a compromise between full support and ventilation. This design reduces mechanical stress on cables, particularly small-diameter control, instrumentation, and communication cables, while still allowing some heat dissipation .

Key Features

• Continuous Support: The solid bottom prevents cable sagging and provides uniform support along the tray length.
• Ventilation Holes: Perforations allow limited airflow, helping to dissipate heat generated by power cables.
• Material Options: Typically made from aluminum, galvanized steel, stainless steel, or fiberglass-reinforced plastic (FRP) depending on environmental conditions .
• Aesthetic and Functional Benefits: Cable troughs prevent visible drooping of small cables, making them suitable for installations where appearance and neatness are important .

Applications

• Mixed Cable Systems: Ideal for installations with a combination of power, control, and communication cables.
• NEC Compliance: Single conductor and Type MV cables can be installed in ventilated troughs, whereas solid-bottom trays are not permitted for these cable types .
• Industrial and Commercial Settings: Used where moderate ventilation is sufficient and additional cable support is desired.
• Aesthetic Installations: Preferred when cable drooping must be minimized for visual or organizational reasons .

Comparison with Other Cable Tray TypesTray TypeSupportVentilationTypical UseLadder TrayRungs onlyMaximum airflowPower cables, high heat dissipationCable Trough (Ventilated)Solid bottom with perforationsModerate airflowMixed cables, small-diameter cables, aesthetic installationsSolid-Bottom TrayFully enclosedMinimal airflowEMI/RFI sensitive circuits, protection from debris or moistureInstallation Considerations

• Rung Spacing: Typically, ladder trays use 6–12 inch spacing, while cable troughs provide continuous support, eliminating sagging concerns.
• Load Capacity: Cable troughs support moderate cable loads; for heavy power cables, ladder trays may be preferred.
• Maintenance: Open perforations allow easier inspection and cable management compared to solid-bottom trays.
• Environmental Factors: Material selection should consider corrosion, temperature, and chemical exposure .

In summary, cable troughs (ventilated trough trays) are a versatile cable tray type that balances cable support, ventilation, and aesthetics, making them suitable for mixed cable systems and installations where cable appearance and mechanical protection are important .