Cable tray installation requirements and specifications
As an auxiliary project of wiring engineering, cable tray has no professional standard guidance at present, and the specifications and procedures of various manufacturers lack universality. Therefore, the design and selection process must reasonably select appropriate cable tray according to the cable type and quantity of weak current systems. Let's understand the installation requirements and specifications of cable tray together!
(1) Determine the direction: according to the floor plan of the building, combined with the installation of air conditioning pipes and electrical pipes, the difficulty of maintenance and the density of cable lines to determine the best path of cable tray. Indoors, try to erect along the walls, pillars, beams and floors of the property. In this way, when using the comprehensive corridor, it is necessary to consider the parallel erection on one side or above the piping, and try not to cross the induction line and the branch line. When not borrowed from other pipe frames, you need to set up your own columns.
2) Load calculation: calculate the cable weight per unit length in the longitudinal section of the cable tray.
(3) determine the width of the cable tray: according to the number of cables, the diameter of the cable and the interval of the cable, the form, specification, the length of the arm, the length of the pillar, the interval, the width and the number of layers of the rack are determined.
(4) determine the installation method: according to the site installation conditions to determine the fixed method of bridge, choose hanging, vertical, side wall type or hybrid. Connectors and connectors are usually supplied in sets. In addition, suitable covers are selected according to the bridge structure.
5) Draw the floor plan and cross-section of the cable bridge, draw the space map of some parts, and draw the material table.
2. When used in combination with the power cable support, the linear sides of the power cable and the weak current cable shall be separated by partitions.
3. When the weak current cable and other low-voltage cables are used in combination, in order to avoid mutual interference, the weak current cable of the weak current system with an external shielding layer must be strictly selected.
4. Installation requirements of cable tray
1) when the trough type large span cable bridge enters the real estate object from the outdoor, the slope to the outside of the bridge should be above 1/100.
2) When the cable tray crosses the electrical equipment, the net distance between them is more than 0.5m.
3) 2 groups of cable tray parallel laying at the same height, the net distance between the 0.6m above.
4) Draw the route of the bridge on the parallel diagram, indicating the coordinates or positioning size and elevation of the starting point, end point, bend point, branch point and lifting point of the bridge. If you can draw the side view of the bridge shaft, the material statistics will be more accurate.
Straight section: indicate the full length, bridge grade, elevation, model and specification. Curve points and branch points: The model and specifications of the steering plate used are clearly stated. Lifting section: indicate the elevation change, which can also be represented by some large sample drawings or profiles.
5) The support points of the bridge frame such as the spacing, installation method, model specification and elevation of the pillar, arm or non-standard branch and skeleton can be listed on the plane, or can be represented by different cross-sectional diagrams, single-line diagrams or large sample diagrams.
6) The location of the cable lead-out point and lead-out method Generally speaking, the lead-out of multiple cables can be installed on the shelf vertically with the vertical bending plate, and the lead-out of a small number of cables can be carried out with a guide plate or conduit, as long as the lead-out method is indicated.
7) The cable tray must be more than 2.2 meters higher than the ground, the upper part of the bridge shall not be more than 0.3 meters away from the ceiling or other obstacles, the width of the bridge shall not be less than 0.1 meters, and the filling rate of the cross section within the bridge shall not exceed 50%.
8) vertical laying cable tray cable, and the upper end of the cable every 1.5 meters fixed on the rack support, horizontal laying, every cable at the front end, end, turn and interval 3~5 meters fixed once.
9) When installed on the back of the ceiling, the open surface of the trough cover shall maintain a vertical free space of 80mm, and the utilization rate of the trough section shall not exceed 50%.
10) The cables laid on the trunking may not be bundled. The cables in the trunking shall be straight. The cables in the trunking shall not cross as far as possible to prevent the cables from being exposed outside the trunking. For the parts of cables entering and leaving the trunking, the vertical pipes shall be bundled and fixed with corners. Please fix the cables on the cable support every 1.5 meters.
11) When laying lines on horizontal, vertical bridges, and vertical pipes, tie the cables together. 4 pairs of cable bundles 24, 25 pairs of above trunk cables, optical cables and other signal cables must be bundled according to the type of cable, cable diameter, cable core number. Bundling intervals shall not be less than 1.5 m. Buttons must be evenly spaced and moderately loose.
12) When laying bridge horizontally, the supporting interval is usually 1.5-3m. When laying vertically, the interval fixed on the structure of real estate objects is preferably less than 2m.
The above is the cable tray installation requirements and specifications, if you need to know more, you can contact us at any time!
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