What Is an Electrical Cable Tray?

An electrical cable tray is a structural support system designed to carry, organize, and route electrical cables. Cable tray systems are widely used to distribute power, control, instrumentation, and communication cables throughout industrial facilities. 

Cable trays differ from raceways such as conduit. A raceway is generally an enclosed system that provides a protected pathway for conductors, while cable trays are typically open or ventilated support structures. Their open construction provides accessibility, airflow, and heat dissipation while making maintenance and future system modifications easier. 

Common types of cable trays include ladder, solid-bottom, perforated or trough, wire mesh, and channel trays. From a prefabrication perspective, these systems provide an important advantage: sections can be measured, cut, fitted, accessorized, labeled, and combined with supports off-site so that field crews receive installation-ready assemblies. 

At DuFab Manufacturing, we specialize in the prefabrication of cable tray sections, supports, and accessories.  We prepare these components as coordinated assemblies before they arrive in the field. This approach can reduce on-site labor, improve consistency, and help simplify installation. Contact Us to learn more. 

Cable Trays: Types, Materials, and Configurations 

Selecting the appropriate electrical cable tray depends on cable type, load, environment, ventilation requirements, corrosion exposure, and facility specifications. 

Cable Tray Type	Common Materials	Typical Industrial Uses	Prefabrication Potential
Ladder	Steel, aluminum, FRP	Power and control cables	Excellent for modular runs
Solid bottom	Steel, aluminum	Sensitive or protected cable routes	Good for preassembled sections
Perforated/trough	Steel, aluminum	Power, control, instrumentation	Excellent for modular assemblies
Wire mesh	Steel	Data and communication cables	Good for lightweight assemblies
Channel	Steel, aluminum, FRP	Smaller cable quantities	Good for compact modules

Cable trays are commonly manufactured from galvanized or stainless steel, aluminum, and Fiberglass-Reinforced Plastic (FRP). Steel provides strength for demanding applications, while aluminum combines strength with reduced weight. FRP offers corrosion resistance, low weight, and non-magnetic characteristics, making it useful in certain industrial environments. For off-site assembly, material selection should also account for module weight, lifting requirements, connection methods, and transportation to the project site. 

Cable Management and Tray Accessories for Prefab Assemblies 

Prefabrication does not have to stop with the tray itself. Covers, dividers, splice plates, splice kits, fittings, bonding components, and other accessories can be incorporated into assemblies before shipment. Splice and connection kits can be packaged with the appropriate modules, reducing the time field personnel spend locating individual components.  

Pre-installation tagging is equally valuable. Clearly labeled tray sections can correspond with drawings, elevations, areas, and installation sequences, helping crews identify where each assembly belongs. For projects separating power, controls, and communications, dividers can also be installed off-site according to the approved cable management plan. 

Cable Tray Support Structures: Design and Prefab Considerations 

Electrical cable trays commonly use strut, trapeze supports, brackets, and other structural support systems. These components present another opportunity for prefabrication. Rather than completing extensive cutting and welding in the field, standardized support assemblies can be produced off-site.  

Predrilled connections, cut-to-length strut, brackets, and hardware can arrive as complete kits or assemblies. Engineering requirements remain essential. Prefabricated supports should be designed using applicable load tables and account for the tray, cables, accessories, environmental loads, and other project-specific conditions. 

National Electrical Code and Compliance 

In the United States, NEC Article 392 provides primary requirements for cable tray installations. Project documentation should identify permitted wiring methods, cable loading requirements, grounding and bonding provisions, and other applicable criteria. 

Specifications may also require compliance with relevant NEMA VE-1 manufacturing requirements and NEMA VE-2 installation guidance, along with applicable UL requirements. Prefabrication does not replace these obligations. Instead, it can create a controlled process for incorporating specified components and verifying assemblies before shipment. 

Cable Trays Seismically Supported 

Facilities with seismic requirements need additional engineering considerations. Depending on the facility and applicable design basis, certain cable trays, including designated SC-I or SC-II/I systems in specialized applications, may require supports and bracing engineered for seismic loads. 

Where appropriate, bracing can become part of the prefabrication package. Standardized seismic bracing modules can be prepared off-site according to engineered requirements, reducing field fabrication. 

Design notes should clearly identify applicable codes, project seismic criteria, support loads, and any specialized standards required by the facility. Nuclear and other highly regulated applications may also reference requirements such as NRC Regulatory Guide 1.61. 

Bonding Cable Trays and Grounding Practices 

Bonding and grounding requirements must be coordinated with the overall electrical design. Depending on the approved system, bonding may involve listed connectors, bonding jumpers, straps, or other specified methods. For prefabricated assemblies, bonding jumpers and associated hardware can be prepared as kits or installed where permitted before shipment.  

Equipment interfaces may also require specified bonding solutions, including suitable bonding glands where required by the design. Preparing these components off-site helps make bonding requirements visible and repeatable rather than leaving every detail to field assembly. 

Installation, Handling, and Field Integration 

A successful prefab-to-field process begins well before delivery. Tray routes and supports are coordinated first, followed by shop fabrication, inspection, labeling, packaging, transportation, staging, lifting, installation, and final field connections. 

Modules should be designed around realistic transportation and lifting limits. Pre-cut penetrations and predrilled mounting holes can further reduce field modifications when permitted by the design and properly coordinated. The goal is simple: maximize completed work before the assembly reaches the installation area. 

Fire Safety, Spacing, and Ampacity 

Cable tray design must also account for fire protection, spacing, cable segregation, and ampacity. In applications with fire exposure, specifications may require fire-retardant cable jackets or other fire-protection measures. Power, control, and data cables may require specific spacing or dividers.  

Where trays are stacked or cable quantities are significant, designers must also evaluate heat dissipation and applicable ampacity requirements. These requirements should be documented before prefabrication begins so that tray dimensions, dividers, supports, and module configurations arrive correctly assembled. 

Cost, Schedule, and Risk Reduction 

Comparing prefabrication with traditional site-built installation should include more than material costs. Contractors should evaluate shop labor, field labor, equipment requirements, material handling, rework, schedule impacts, and installation productivity. 

Real project metrics, such as field hours avoided, installation time per module, rework rates, and schedule days saved, provide the strongest basis for measuring results. Off-site assembly can also reduce exposure to common field risks, including congestion, inconsistent fabrication, material staging problems, excessive field cutting, and coordination conflicts. 

Build Smarter Cable Tray Systems  

Electrical cable trays provide an efficient way to organize, support, and distribute electrical cables across industrial facilities, including manufacturing plants, utilities, commercial facilities, and specialized power-generation environments. Their modular nature also makes them well suited to prefabrication. 

By moving cable tray sections, supports, accessories, connection kits, and other repeatable work into an off-site assembly environment, project teams can reduce field fabrication, improve quality control, and create a more predictable installation process. If you are ready to evaluate prefabricated cable tray assemblies for your next project Request a DuFab Quote.