Cable Trunking vs. Bridge: A Comparison of the Core Differences 

Cable Trunking and Cable Tray/Bridge are both support systems used for cable laying, but they are significantly different in terms of their construction, use and application scenarios. The following is a detailed comparison: 

1. Definition and structure 

Comparison item Cable Trunking Bridge (Cable Tray/Bridge) 

Structure Fully enclosed (with cover), similar to rectangular conduit Open or semi-enclosed (ladder/trough/grid type) 

Material PVC, galvanised steel, aluminium alloy Galvanised steel, aluminium alloy, stainless steel, FRP 

Typical appearance Square or Arc shaped closed channel body Step-like cross (step type) or U-channel (channel type) 

2. Core Functional Differences 

Comparison Item Trough Bridge 

Main Purpose Protecting weak power lines (e.g. network cables, telephone lines) Carrying medium to large-sized cables, such as power cables and telecommunication cables 

Protection Protection Against Dust, Moisture, and Electromagnetic Interference (EMI) Weakly protected by open design, but with good heat dissipation 

Load-bearing Capacity Lower (suitable for lightweight cables) Higher (supports heavy cables) Heat dissipation Poorly protected from heat (can support heavy cables) Heavy duty cables) 

Heat dissipation Poor (closed structure) Excellent (open structure) 

Installation Flexibility Removal of cover plate required for cabling, troublesome to add or change at later stage Directly laid cables, easy to maintain and expand 

3. Scenarios 

Typical application scenarios for the type 

Wireway - Office network cabling

- Household weak electricity line (TV line, network line)

- Machine room antistatic floor under the line 

Bridge - Power cable laying (substation, factory)

- Data centre backbone cabling

- Outdoor cable overhead support 

4. Comparison of installation methods 

Comparison of trunking bridges 

Installation location Concealed wall mounting, open mounting, or floor mounting Suspended ceiling, bracket fixing, or wall mounting 

Wiring method Need to open the cover plate for threading, and then closed Cables are directly put into trays or ladder traverses 

Extensibility Modification requires reassembly and dismantling Cables can be added directly without dismantling the structure 

5. Costs and maintenance 

Comparison of trunking bridges 

Costs Lower (PVC material common) Higher (metal material mainly) Cost Lower (PVC) Higher (metal-based) 

Maintenance Difficulty More troublesome (need to remove cover for maintenance) Convenient (open design, easy to see) 

Summary: How to choose?

Choose trunking: 

✅ Weak-computer cabling (network cables, telephone cables) 

✅ Dust-proof, anti-interference applications 

✅ Small-scale, fixed-line laying 

Choose bridge: 

✅ Power cables or large-capacity communication cables 

✅ Heat dissipation, easy maintenance 

✅ Industrial environments or high-density cabling in data centres 

The key difference is: trunking focuses on protection, and bridge focuses on load-carrying and heat dissipation. Just choose according to the actual needs!