1. Cable trays are classified into steel plates, aluminum alloys, stainless steel, fiberglass, and inorganic materials according to their material types; Classified by structure, there are ladder type, perforated tray type, non perforated tray type, etc; Classified according to fire protection requirements, there are ordinary and fire-resistant types; There are regular and energy-saving types in terms of performance classification. Steel cable trays are classified into three types based on surface protection layer: hot-dip galvanized type, composite corrosion-resistant type, and composite high corrosion-resistant (color steel) type. Among them, composite high corrosion-resistant (color steel) cable trays are a new generation of products made of color steel plates, which have the characteristics of fast installation, energy conservation, light weight, and high strength. They have been developed and produced by Shanghai Zhangxiang Electrical Complete Set Co., Ltd. The surface protection layer should be selected based on the usage environment.

2. 电缆桥架水平安装时，宜根据在额定荷载下电缆桥架挠度不大于长度的1/200，按荷载选取跨距作支撑，且支撑点间距宜为1500～3000mm。垂直安装时，其固定点间距不宜大于2000mm。当不能满足要求时，宜采用大跨度电缆桥架。

When installing cable trays horizontally, it is advisable to select the optimal span as the support according to the load, and the spacing between support points should be 1500-3000mm, based on the cable tray deflection not exceeding 1/200 of its length under rated load. When installed vertically, the spacing between fixed points should not exceed 2000mm. When the requirements cannot be met, large-span cable trays should be used.

3. 除技术夹层和特殊场合外，电缆桥架水平段距地面的高度不宜低于2500mm，垂直段距地面的高度不宜低于1800mm。除在电气专用房间内外，当不能满足要求时，应采取防机械损伤措施。

3. Except for technical interlayer and special occasions, the height of the horizontal section of the cable tray from the ground should not be less than 2500mm, and the height of the vertical section from the ground should not be less than 1800mm. When the requirements cannot be met, measures to prevent mechanical damage should be taken, except in and outside electrical rooms.

4. 电缆桥架多层安装时,其层间净距离应符合下列规定:1)电力电缆桥架之间不应小于300mm。

When installing cable trays in multiple layers, the clear distance between layers should comply with the following regulations: 1) The distance between power cable trays should not be less than 300mm.

5. 电信（控制）电缆桥架与电力电缆桥架之间不应小于500mm。当有屏蔽措施时，不应小于300mm.

5. The distance between the telecommunications (control) cable tray and the power cable tray should not be less than 500mm. When there are shielding measures, it should not be less than 300mm

6. 控制电缆桥架之间不应小于200mm。

6. The distance between control cable trays should not be less than 200mm.

7. 电缆桥架上部距顶棚、楼板或梁等其他障碍物不宜小于300mm。8. 当两组或两组以上电缆桥架在同一高度平行安装时，各相邻电缆桥架之间应留有满足维护、检修的距离。

7. The distance between the upper part of the cable tray and other obstacles such as the ceiling, floor slab, or beam should not be less than 300mm. When two or more sets of cable trays are installed in parallel at the same height, there should be a distance between adjacent cable trays that meets maintenance and repair requirements.

9. 在电缆桥架内可以无间距敷设电缆。电缆总截面积与电缆桥架内横断面面积之比，电力电缆不应大于40%,控制电缆不应大于50%。10. 下列不同电压、用途的电缆，不宜敷设在同一层的电缆桥架上:1

9. Cables can be laid without gaps within the cable tray. The ratio of the total cross-sectional area of cables to the cross-sectional area inside the cable tray should not exceed 40% for power cables and 50% for control cables. 10. The following cables with different voltages and purposes should not be laid on the same layer of cable trays: 1

）1kV以上与1kV及以下的电缆。2)向同一负荷供电的两回路电源电缆。

）Cables above 1kV and below 1kV. 2) Two circuit power cables supplying power to the same load.

3）应急照明和其他照明的电缆。4）电力电缆与电信电缆。

3) Emergency lighting and other lighting cables. 4) Power cables and telecommunications cables.

11. 当受条件限制需敷设在同一电缆桥架上时，应采用金属隔板隔开。12. 电缆桥架不宜安装在热力管道的上方及腐蚀性液体管道的下方。对于腐蚀性气体的管道，当气体的密度大于空气时，宜安装在其上方;当气体的密度小于空气时，宜安装在其下方。13. 电缆桥架转弯处的弯曲半径，不应小于桥架内电缆更小允许弯曲半径的值。

11. When laying on the same cable tray due to limitations, metal partitions should be used to separate them. 12. Cable trays should not be installed above thermal pipelines or below corrosive liquid pipelines. For pipelines with corrosive gases, when the density of the gas is greater than that of air, it is advisable to install them above it; When the density of the gas is less than that of air, it should be installed below it. The bending radius at the turning point of the cable tray should not be less than the maximum value of the minimum allowable bending radius of the cable inside the tray.

14. 电缆桥架不得在穿过楼板或墙壁处进行连接。

14. Cable trays shall not be connected at points where they pass through floors or walls.

15. 电缆桥架在穿越防火墙及防火楼板时,应采取防火封堵措施。

15. When cable trays pass through firewalls and fireproof floors, fire blocking measures should be taken.

16. 钢制电缆桥架直线段长度超过30m、铝合金或玻璃钢制电缆桥架长度超过l5m时，宜设置伸缩节。

When the straight section length of steel cable trays exceeds 30m, and the length of aluminum alloy or fiberglass cable trays exceeds 15m, expansion joints should be installed.

17. 电缆桥架跨越建筑物变形缝时,应设置补偿装置。

When cable trays cross deformation joints in buildings, compensation devices should be installed.

18. 金属桥架及支架、玻璃钢制电缆桥架内专用的接地干线，其全长应不少于2处与接地保护导体(PE线)可靠连接。

18. The dedicated grounding main line inside the metal bridge and bracket, as well as the fiberglass cable bridge, should be reliably connected to the grounding protective conductor (PE line) at no less than 2 places along its entire length.

19. 热浸镀锌电缆桥架之间的连接板的两端可不跨接接地线，但连接板两端应有不少于2个有防松螺母或防松垫圈的连接固定螺栓。

19. The two ends of the connecting plate between hot-dip galvanized cable trays may not be connected to the grounding wire, but the two ends of the connecting plate should have at least two connection fixing bolts with locking nuts or washers.

20. 非热浸镀锌电缆桥架之间的连接板的两端跨接铜芯接地线，接地线更小允许截面积不应小于4mm2。

20. The two ends of the connecting plate between non hot-dip galvanized cable trays should be connected to a copper core grounding wire, and the minimum allowable cross-sectional area of the grounding wire should not be less than 4mm2.

21. (19）户内相同电压的电缆并列明敷时,除敷设在电缆桥架内外，电缆之间的净距不应小于35mm，且不应小于电缆外径。1kV及以下电力及控制电缆与1kV以上电力电缆宜分开敷设,当需并列敷设时,其净距不应小于150mn。

When cables of the same voltage are laid in parallel and exposed indoors, except when laid inside and outside the cable tray, the clear distance between the cables should not be less than 35mm and should not be less than the outer diameter of the cable. Power and control cables of 1kV and below should be laid separately from power cables of 1kV and above. When parallel laying is required, the clear distance should not be less than 150mn.

22. (21）电力电缆在桥架内敷设，容积率不宜超过40%，控制电缆不宜超过50%。

22. (21) Power cables should be laid inside the bridge, with a plot ratio not exceeding 40%, and control cables not exceeding 50%.