Views: 0 Author: Site Editor Publish Time: 2026-08-22 Origin: Site
Selecting the correct cable tray is not simply a matter of choosing the right width and height. For industrial plants, commercial buildings, infrastructure projects and data centers, the cable tray must safely support the total cable load over the required support span.
Cable tray load capacity is therefore a critical engineering parameter.
This guide explains the key concepts behind cable tray load capacity, including Safe Working Load (SWL), support span, deflection, cable weight, tray material and thickness, with particular attention to IEC 61537 and a 2-meter support span.
The information is intended to help electrical engineers, MEP contractors, EPC companies, consultants and procurement teams select the appropriate cable tray for their projects.
Cable tray load capacity is the maximum distributed cable weight that a cable tray system is designed to support safely under specified installation conditions.
It is normally expressed as:
kg/m — kilograms per meter
or
N/m — Newtons per meter
For example, a cable tray with a stated load capacity of 150 kg/m at a 2-meter support span means the tray has been evaluated for a uniformly distributed load of 150 kilograms per meter under the specified test and installation conditions.
However, cable tray load capacity cannot be determined from width alone.
It depends on several factors, including:
Cable tray width
Cable tray side rail height
Material
Steel thickness
Tray profile and reinforcement
Perforation pattern
Support span
Connection method
Installation configuration
Deflection requirements
Applied load distribution
A wider tray does not automatically mean a proportionally higher load capacity.
SWL stands for Safe Working Load.
It is the allowable working load that a cable tray system can safely support under defined installation conditions.
For cable tray applications, SWL is normally considered together with the support span.
For example:
SWL: 150 kg/m at 2,000 mm support span
This information is much more useful than simply stating:
Cable Tray Load Capacity: 150 kg/m
because the same cable tray may have different load performance at 1.5 m, 2 m or 3 m support spans.
As the distance between supports increases, the bending moment and deflection of the tray generally increase.
Therefore:
Longer support span = higher structural demand
and
Shorter support span = generally higher allowable load
For this reason, cable tray load tables should always specify the support span.
A 2-meter support span is widely used as a practical reference when evaluating cable tray load performance.
For example, a project specification may require:
Support Span: 2,000 mm
The tray is then installed between supports with a nominal 2-meter distance, and the load is distributed along the tray.
When comparing cable tray manufacturers, engineers should make sure that the load ratings are based on the same support span.
Comparing:
Manufacturer A: 200 kg/m at 2 m span
Manufacturer B: 250 kg/m at 3 m span
does not provide a direct comparison.
The support span must be considered together with the stated SWL.
IEC 61537 is an important international standard for cable tray and cable ladder systems.
The standard provides requirements and test methods related to the mechanical performance of cable tray and cable ladder systems.
Load testing typically evaluates the behavior of the tray under a specified uniformly distributed load.
A laboratory test may evaluate parameters such as:
Working load
Deflection
Structural stability
Permanent deformation
Mechanical failure
Connection performance
The exact test configuration, acceptance criteria and declared load should always be confirmed with the applicable edition of the standard and the testing laboratory.
For manufacturers, third-party testing through laboratories such as SGS or TÜV can provide independent evidence of product performance.
A typical cable tray load test uses a representative tray section installed on supports at a specified span.
For a 2-meter span test, the setup may include:
Support Span: 2,000 mm
Load Type: Uniformly Distributed Load (UDL)
Test Sample: Representative Cable Tray
The test load is distributed along the tray and the resulting deflection is measured.
A simplified testing process is:
The cable tray is installed on supports according to the specified support arrangement.
A uniformly distributed load is applied to simulate the weight of cables installed in the tray.
The vertical deflection of the tray is measured, particularly around the critical span area.
The tray is inspected for excessive deformation, cracking, connection failure or other signs of structural instability.
The measured performance is compared with the applicable requirements and the manufacturer's declared load.
Steel thickness is an important factor, but it is not the only factor determining load capacity.
Two cable trays with the same thickness may have different load performance because of differences in:
Side rail geometry
Flange design
Bottom profile
Ribbing
Perforation
Reinforcement
Width
Height
Material properties
Connection design
For example, a 1.5 mm tray with a strong structural profile may perform differently from a flat 1.5 mm tray.
Therefore, engineers should not estimate cable tray load capacity from steel thickness alone.
Tested or engineered load data is preferred for project specifications.
The following table provides an example engineering reference format for steel perforated cable trays at a 2,000 mm support span.
The actual Safe Working Load of a product should be confirmed by product testing, engineering calculations and/or a third-party test report. The values below should therefore not be interpreted as an IEC 61537 certification unless supported by an applicable test report.
Cable Tray Size | Thickness | Support Span | Reference SWL* |
|---|---|---|---|
100 × 50 mm | 1.0 mm | 2,000 mm | 75 kg/m |
100 × 100 mm | 1.0 mm | 2,000 mm | 90 kg/m |
150 × 100 mm | 1.0 mm | 2,000 mm | 105 kg/m |
200 × 100 mm | 1.2 mm | 2,000 mm | 130 kg/m |
200 × 150 mm | 1.2 mm | 2,000 mm | 145 kg/m |
300 × 100 mm | 1.2 mm | 2,000 mm | 150 kg/m |
300 × 150 mm | 1.2 mm | 2,000 mm | 165 kg/m |
400 × 100 mm | 1.5 mm | 2,000 mm | 180 kg/m |
400 × 150 mm | 1.5 mm | 2,000 mm | 200 kg/m |
500 × 100 mm | 1.5 mm | 2,000 mm | 205 kg/m |
500 × 150 mm | 1.5 mm | 2,000 mm | 220 kg/m |
600 × 100 mm | 2.0 mm | 2,000 mm | 240 kg/m |
600 × 150 mm | 2.0 mm | 2,000 mm | 260 kg/m |
800 × 100 mm | 2.0 mm | 2,000 mm | 275 kg/m |
800 × 150 mm | 2.0 mm | 2,000 mm | 295 kg/m |
800 × 200 mm | 2.0 mm | 2,000 mm | 320 kg/m |
1000 × 100 mm | 2.5 mm | 2,000 mm | 320 kg/m |
1000 × 150 mm | 2.5 mm | 2,000 mm | 345 kg/m |
1200 × 100 mm | 2.5 mm | 2,000 mm | 360 kg/m |
1200 × 150 mm | 2.5 mm | 2,000 mm | 390 kg/m |
1200 × 200 mm | 2.5 mm | 2,000 mm | 420 kg/m |
*Reference SWL: These values are provided as a reference format for product selection and should be replaced or validated with Shenzhen Wanan's actual tested or engineered values before being used as certified load ratings.
Before selecting a cable tray, the engineer should estimate the total cable load.
A simplified calculation is:
Required Load = Cable Weight + Allowance for Future Cables
For example, assume the cables installed in one meter of tray have a combined weight of:
100 kg/m
If the project requires a 20% allowance for future expansion:
100 × 1.20 = 120 kg/m
The selected cable tray should therefore have an appropriate declared SWL above the required working load, subject to the project's design criteria and applicable safety requirements.
Existing cable load:
100 kg/m
Future allowance:
20 kg/m
Required working load:
120 kg/m
A cable tray with a suitable tested SWL above 120 kg/m could then be considered, provided the support span, installation conditions and project specifications are compatible.
Cable tray selection should start with the cable schedule.
The engineer should identify:
Cable type
Cable diameter
Cable weight
Number of cables
Cable arrangement
Total cable weight per meter
Future expansion allowance
For example:
Cable Type | Quantity | Weight | Total |
Power Cable | 10 | 5 kg/m | 50 kg/m |
Control Cable | 20 | 1 kg/m | 20 kg/m |
Communication Cable | 20 | 0.5 kg/m | 10 kg/m |
Future Allowance | — | — | 20 kg/m |
Total Required Load | 100 kg/m |
This allows the project engineer to select the cable tray based on actual loading requirements instead of choosing a tray based only on its dimensions.
Increasing the tray width increases the available cable installation area, but structural performance also depends on the tray profile and reinforcement.
Higher side rails can improve structural stiffness and may increase load-carrying capability.
Increasing material thickness generally improves structural resistance, but the final performance depends on the complete tray geometry.
Support span is one of the most important factors.
A tray tested at 2 m span should not automatically be assumed to have the same SWL at 3 m span.
Common cable tray materials include:
Pre-Galvanized Steel
Hot-Dip Galvanized Steel
Zinc-Aluminum-Magnesium Coated Steel
Stainless Steel
Powder-Coated Steel
Material selection should consider both mechanical performance and the environmental conditions of the project.
Perforated cable trays, solid bottom trays and cable ladders have different structural characteristics.
Their load ratings should therefore be evaluated according to their individual designs.
Cable ladders are commonly selected for applications requiring high cable loads and long support spans.
Perforated cable trays are widely used for:
Power distribution
Control cables
Industrial automation
Commercial buildings
Data centers
Electrical rooms
Cable ladders are often used for:
Heavy power cables
Large cable bundles
Industrial plants
Power stations
Utility infrastructure
The best solution depends on the cable weight, support span, environmental conditions and project requirements.
A practical selection process is:
Calculate the cable weight in kg/m.
Consider the project's future cable requirements.
For example:
2,000 mm
Choose between:
Perforated Cable Tray
Solid Bottom Cable Tray
Cable Ladder
Consider both structural requirements and corrosion environment.
Make sure the manufacturer's declared or tested SWL is suitable for the required load.
For international projects, check whether IEC 61537 testing or another specified standard is required.
A cable tray load table is useful only when the test conditions are clearly stated.
When comparing suppliers, ask for:
Cable tray size
Material
Thickness
Support span
Load type
SWL
Deflection
Test standard
Test report number
Testing laboratory
For international projects, a third-party test report from a recognized laboratory can provide additional confidence for consultants, EPC contractors and procurement teams.
Data centers require reliable cable management because cable quantities can be high and future expansion is often expected.
Cable tray selection should consider:
High cable density
Power cable weight
Fiber and communication cable routing
Redundancy
Future expansion
Support spacing
Installation access
Grounding and bonding
Corrosion protection
For data center projects, load capacity should be evaluated together with the complete cable management system rather than considering the tray body alone.
Environmental conditions are particularly important for projects in Southeast Asia.
Malaysia, Indonesia, Vietnam, Thailand and the Philippines can have:
High humidity
Heavy rainfall
High temperatures
Coastal salt exposure
Industrial pollution
Therefore, both mechanical performance and corrosion resistance should be considered.
Depending on the application, project engineers may consider:
Hot-Dip Galvanized Steel
for demanding industrial environments,
Zinc-Aluminum-Magnesium Coated Steel
for enhanced corrosion resistance with high durability,
or
Powder-Coated Steel
when a specific coating system and appearance are required.
The appropriate material should always be selected according to the project's environmental classification and specification.
Different markets may specify different standards for cable tray systems.
IEC 61537 is an international standard used for cable tray and cable ladder systems.
JB/T 10216-2013 is a Chinese industry standard covering cable tray systems.
For export projects, the required standard should be confirmed with the consultant, EPC contractor or end customer.
Where international certification is required, manufacturers should work with an accredited testing laboratory to establish the appropriate test scope.
When selecting a cable tray manufacturer, do not compare suppliers only by price.
Consider:
Manufacturing experience
Product range
Material options
Steel thickness
Load test capability
IEC 61537 testing
Quality management system
Factory production capacity
OEM capability
Export experience
Technical support
Documentation
A reliable manufacturer should be able to provide dimensional drawings, material specifications, load information and relevant test documentation for project approval.
Shenzhen Wanan Industrial Co., Ltd. is a China-based manufacturer of cable management systems and photovoltaic mounting systems.
Our cable tray production covers a wide range of sizes, materials and configurations for industrial, commercial, infrastructure and data center projects.
Our cable tray solutions include:
Perforated Cable Tray
Solid Bottom Cable Tray
Cable Ladder
HDG Cable Tray
ZAM Cable Tray
Powder Coated Cable Tray
Cable Tray Accessories
We support customized dimensions, materials, thicknesses and project-specific requirements.
For projects requiring load verification, our engineering team can work with customers and testing laboratories to define appropriate sample sizes, support spans and test requirements.
Cable tray load capacity is the amount of uniformly distributed cable weight that a cable tray system can safely support under specified installation conditions.
SWL means Safe Working Load. It is the allowable working load of the cable tray under defined conditions such as support span, tray configuration and installation method.
There is no single load rating for all cable trays. Load capacity depends on tray dimensions, material, thickness, structural design and support span. A tested load chart should be used for project selection.
There is no universal support span for every project. Common project designs may use spans such as 1.5 m, 2 m or 3 m depending on the tray system and project specification.
A 2m span means the distance between the supporting points of the cable tray is approximately 2,000 mm.
Generally, increasing thickness can improve structural resistance, but thickness alone does not determine the final load capacity. Tray geometry, width, height, reinforcement and support span also matter.
IEC 61537 may be specified for international projects. The required standard depends on the project specification, market and consultant requirements.
Not necessarily. Manufacturers and testing laboratories may establish a test program using representative product sizes, depending on the applicable standard, product family and test scope. The exact test matrix should be agreed with the testing laboratory.
Cable tray load capacity should always be evaluated together with SWL, support span, tray dimensions, material, thickness and installation conditions.
For a 2-meter support span, engineers should compare cable trays using clearly defined load data rather than relying only on tray width or steel thickness.
For industrial, commercial and data center projects, a properly selected cable tray can provide reliable cable support while allowing sufficient capacity for future expansion.
When selecting a cable tray manufacturer, ask for complete technical information including dimensions, material, thickness, support span, SWL and applicable test reports.
Need a cable tray load chart for your project? Contact Shenzhen Wanan Industrial for product dimensions, technical specifications and customized cable tray solutions.
MOB/Whatsapp:+86 18823394830
Email: admin@szwaindustry.com
Address：Wanan Industrial Park, Fengdong Village, Xinxu Town, Huicheng District, Huizhou，Guangdong
Whatsapp: +86-18823394830 
