Attention to details when selecting cable trays

1. When laying cable trays horizontally, the height from the ground is generally not less than 2.5m. When laying vertically, the part below 1.8m from the ground should be protected with a metal cover plate, except when laying in an electrical room. If the cable tray is horizontally laid on the equipment interlayer or upper level raceway and is less than 2.5m, protective grounding measures should be taken.

2. In engineering design, the layout of cable trays should be comprehensively compared based on factors such as economic rationality, technical feasibility, and operational safety to determine the best solution, while fully meeting the requirements of construction, installation, maintenance, and cable laying.

3. When used in corrosive environments, cable racks, cable trays, and their supports and hangers should be made of corrosion-resistant rigid materials. Alternatively, anti-corrosion treatment can be adopted, which should meet the requirements of engineering environment and durability. Aluminum alloy cable racks should be selected for places with high requirements for corrosion resistance or cleanliness.

4. When the cable tray is located in a section with fire protection requirements, fire-resistant or non combustible materials such as plates and nets can be installed on the cable ladder and tray to form a closed or semi closed structure, and fire-resistant coatings and other measures should be taken on the surface of the tray and its supports and hangers. The overall fire resistance performance should meet the requirements of relevant national specifications or standards. Aluminum alloy cable trays should not be used in places with high fire prevention requirements.

5. Cable lines that require electromagnetic interference shielding, or places with protective external shadows such as outdoor sunlight, oil, corrosive liquids, flammable dust, and other environmental requirements. Non perforated tray cable trays should be selected.

6. In areas prone to dust accumulation, cable trays should use cover plates; At public passages or outdoor intersections. The bottom bridge should be equipped with cushion plates or perforated trays.

7. The selection of cable ladder and tray width and height should meet the requirements of filling rate. Generally, the filling rate of cables in the ladder and tray is 40% to 50% for power cables and 50% to 70% for control cables. And it is advisable to reserve a margin of 10% to 252 for project development.

8. When selecting the load level of the cable tray, if the actual span of the cable tray support and hanger is not equal to 2m, the working uniform load of the cable tray should not exceed the rated uniform load of the selected cable tray.

9. Cables with different voltages and purposes should not be laid in the same layer of cable trays:

(1) Cables above and below 1kV:

(2) A double circuit cable that supplies power to the first level load on the same path.

(3) Emergency lighting and other lighting cables:

(4) Power, control, and telecommunications cables.

When cables of different grades are laid in the same cable tray, a partition wall should be added in the middle for isolation.

10. When the straight length of steel cable tray is greater than 30m and the straight length of aluminum alloy cable tray is greater than 15m. When cable trays pass through building expansion (settlement) joints, a compensation allowance of O-30mm should be left. Expansion connection plates should be used at the connection point.

The parameters given above are the most suitable for modern cable tray use and are also the most basic product requirements that cable tray manufacturers should meet. If you have no experience in selecting cable trays, we recommend that you carefully read the summary in this article or call us to inquire about your usage situation and provide you with the most accurate guidance!