Cable Tray Sizing Calculator Excel Download

Calculation Sheet Detail

• No need to input data in the red color high-light
• Enter the cable information in the sheet.
• Enter the value in the yellow color high-ligh.
• The result will show “OK” with Green high-light.
• If “Error” occur in the Result, re-enter the Cable Tray or Cable Ladder size.

Alternate Calculation Sheet >> Cable Trunking Size Calculator

Cable Tray Sizing involves several steps to ensure that it can support the cables it will carry while meeting electrical and safety standards. Here’s a detailed guide:

Steps to Size a Cable Tray

1. Identify the Cable Types and Sizes:
   • Determine the number and types of wires (e.g., power, control, signal) that will be placed in the cable tray sizing.
   • Obtain the diameters and cross-sectional areas of each cable type.
2. Calculate the Total Cross-Sectional Area:
   • Calculate the cross-sectional area of each cable type.
   • Sum up the cross-sectional areas of all cables to get the total area.
3. Apply Fill Ratio:
   • According to standards like NEC (National Electrical Code) or IEC (International Electrotechnical Commission), determine the permissible fill ratio. This is usually around 40-50% for ventilation and heat dissipation.
   • Divide the total cross-sectional area of wire by the fill ratio to get the minimum cross-sectional area of the cable tray.
4. Select Tray Dimensions:
   • Based on the calculated minimum cross-sectional area, choose a cable tray width and height that meets or exceeds this requirement.
   • Ensure the chosen cable tray sizing allows for future expansion if needed.
5. Consider Cable Weight:
   • Calculate the weight of the wires and ensure the cable tray can support this weight without sagging or structural failure.
6. Environmental and Installation Factors:
   • Consider environmental factors such as temperature, chemical exposure, and mechanical impact, which may affect the choice of tray material (e.g., steel, aluminum, fiberglass).
   • Determine whether a solid bottom, ventilated, or ladder-type tray is needed based on the installation environment and wire type.

Example Calculation of Cable Tray Sizing

1. Identify Cables:
   • Suppose you have the following cables:
     • 10 power wires (diameter: 20 mm each)
     • 20 control wires (diameter: 10 mm each)
     • 30 signal wires (diameter: 5 mm each)
2. Calculate Cross-Sectional Areas:
   • Power wires: 𝜋×(10 mm)2×10=3141.6 mm2π×(10 mm)2×10=3141.6 mm2
   • Control wires: 𝜋×(5 mm)2×20=1570.8 mm2π×(5 mm)2×20=1570.8 mm2
   • Signal wires: 𝜋×(2.5 mm)2×30=589.05 mm2π×(2.5 mm)2×30=589.05 mm2
   • Total area: 3141.6+1570.8+589.05=5301.45 mm23141.6+1570.8+589.05=5301.45 mm2
3. Apply Fill Ratio:
   • Assuming a 40% fill ratio: 5301.45/0.4=13253.625 mm25301.45/0.4=13253.625 mm2
4. Select Tray Dimensions:
   • Convert the area to square meters: 13253.625 mm2=0.01325 m213253.625 mm2=0.01325 m2
   • Choose tray dimensions (e.g., 100 mm wide by 200 mm high) that provide sufficient space:
     • 100 mm×200 mm=20000 mm2100 mm×200 mm=20000 mm2
   • This tray size is adequate since 20000 mm² > 13253.625 mm²
5. Check Cable Weight:
   • Ensure the cable tray can support the weight of all combined. Manufacturer specifications will provide load ratings for various tray types and sizes.

Additional Considerations

• Ventilation: Ensure enough ventilation to prevent overheating.
• Support Spacing: Follow standards for support spacing to prevent sagging.
• Expansion: Leave room for potential future.

Standards and References

• NEC: National Electrical Code (NFPA 70)
• IEC: International Electrotechnical Commission standards
• NEMA VE 1: National Electrical Manufacturers Association standards for metal cable trays

By following these steps and standards, you can accurately size a cable tray sizing for your installation needs.

You can request excel calculation sheet here.

Download : Onedrive, Google Drive