October 21, 2023
The cable tray is an accessory project for electrical wiring project. At present, there is no professional standard manual, and manufacturer's specification model G code is impractical. Therefore, design process of motor selection process should be based on low-current cables of installation system structure, look at type and quantity, and efficiently select available jumpers.
(1) Determine direction: According to architectural plan, consider installation status of central air and electrical pipes, convenience of maintenance, and relationship between cable routes to determine best route for cable trays. Indoors, it must be built along walls, columns, beams and concrete floors of building, if an underground complex pipe gallery is allowed for construction, it must be built on side of pipeline. or on a parallel surface above pipeline, and take into account bends and branches as much as possible. To reduce intersection, if other pipe supports are not used, it is necessary to open (support) columns yourself.
(2) Load Calculation: Calculate weight of long and short cables on longitudinal section of cable tray main line.
(3) Determination of bridge width: According to number of distributed cables, cable diameter and distance between cables, determine cable tray model and specification, model size, support arm length, support length and distance, and span. The total width of connection and number of overlay layers.
(4) Specify installation method: specify bridge fixing method according to established site standards, select suspension type, vertical type, external wall type or mixed type, and connecting parts and standard parts. usually provided with aids. For products, in addition, select opposite back cover according to design of bridge.
(5) Draw a planar diagram and sectional diagram of a cable-stayed bridge, draw an internal space diagram for some items, and list raw materials.
(6) When cable tray enters building from outside, outward slope of bridge should not be less than 1/100.
(7) When cable tray crosses energy-consuming equipment, distance between them must be at least 0.5 m.
(8) When laying two sets of cable trays on parallel planes with same aspect ratio, distance between them must be at least 0.6 m.
(9) Draw bridge routers on parallel plane diagram and indicate coordinates or precise positioning specifications and design heights of start point, end station, turn point, branch point, and bridge lift point if you can. Statistical analysis of raw materials will be more accurate if an axonometric diagram is laid across bridge.
Parallel Line Segment: Specify total length, number ofnumber of overlapping layers, design height, model specification, and model specification.
Pivot and Pivot Points: Specify model characteristics and characteristics of commonly used pivot plates.
Elevator section: indicates a design change in height and may also be expressed as partial large scale drawings or sectional drawings.
(10) Support point such as vertical support, support arm or standard support type, construction spacing, installation method, specification model, design height can be listed in catalog on plan, or can be marked with different paragraphs Sectional diagram, single line chart or large scale chart view.
(11) Cable exit position and method. Generally speaking, a large number of cables can be led with a vertical bending plate and a vertical release, and a small number of cables can be led with a guide plate or guide tube, just mark path to lead down.
(12) The cable tray should be approximately 2.2m above road surface. The distance from top of bridge to ceiling or other road barriers must be at least 0.3 m. The total width of bridge must not be less than 0.1 m. The rate cannot exceed 50%.
(13) When laying cable vertically in a cable-stayed bridge, it should be fixed on support frame above cable at a distance of 1.5 km, rotated and fixed at intervals of 3-5 km.
