The connection between the metal ladder, tray or slot box body shall be firm and reliable, and the connection with the protective conductor shall comply with the following provisions:
When the total length of ladder, tray and slot box is not more than 30m, at least 2 places shall be reliably connected with the protective conductor; When the total length is more than 30m, a connection point shall be added every 20m ~ 30m, and the starting end and ending end shall be reliably grounded.
The two ends of the connecting plate between the non galvanized ladder, tray and slot box body shall be bridged with the protective connecting conductor, and the cross-sectional area of the protective connecting conductor shall meet the design requirements.
When the protective connecting conductor is not bridged between the galvanized ladder, tray and slot box body, each end of the connecting plate shall not be less than 2 connecting and fixing bolts with anti loose nuts or anti loose washers.
The distance between bridge hangers in straight section is 1.5m ~ 2m. If suspender support is used, the diameter of suspender shall not be less than 8mm, and fixed support shall be set at lintel.
In the picture, a group of hangers are set on both sides of the turn, and the two groups of hangers are symmetrically arranged with a spacing of no more than 1.5m, otherwise a group of hangers is added in the middle of the turn.
In the picture, a group of hangers are set on both sides of the turn, and the two groups of hangers are symmetrically arranged with a spacing of no more than 1.5m, otherwise a group of hangers is added in the middle of the turn; The distance between the top tray and the floor slab shall not be less than 150mm, and the spacing between the upper and lower trays shall not be less than 150mm.
Picture accurate setting out, processing and installation of bridge and trunking according to the special angle of concrete. WeChat public No.: building hydropower knowledge platform picture straight section steel cable bridge length over 30 meters, aluminum alloy or FRP cable bridge length more than 15 meters with expansion joint; official account: Compensation device shall be set at the deformation joint where the cable tray crosses the building.
Picture: the total length of metal cable tray and its support shall not be less than 2, which shall be connected with the grounding trunk line; Both ends of the bridge shall be reliably connected with the shell of the distribution cabinet or the ground wire row.
The two ends of the connecting plate between non galvanized cable trays are connected with copper core grounding wire. The grounding wire must be paid attention to the special grounding hole on the trunking tray, and the minimum allowable cross-sectional area of the grounding wire shall not be less than 4mm?; Remove the insulating layer under the grounding bolt before connection; The two ends of the connecting plate between galvanized bridges shall not cross the grounding wire, but the two ends of the connecting plate shall not be less than 2 connecting and fixing bolts with anti loose nuts or anti loose washers.
The picture is coordinated with the civil engineering, and holes are reserved in advance for the bridge crossing the wall, floor and other parts.
Picture: the bottom plate of trunking and bridge shall be fixed with metal bolts with the cross arm of supports and hangers (≤ 200mm, fixed with one bolt; > 200mm, fixed with two bolts at 1 / 4 from the edge).
When the bridge crosses the wall and floor, it shall be blocked with incombustible materials; Fire blocking must be done in the bridge crossing the fire compartment.
The installation height of outdoor installation bridge shall not be lower than the height of snow and ponding. At the same time, waterproof cover plate shall be considered to be selected. In and out of outdoor bridge and trunking, the indoor shall be higher than the outdoor to prevent rainwater from flowing into the room.
The above content is about Shandong cable tray http://www.sddlqj.cn/ I hope these contents will be helpful to you. If you have any questions or want more information, please consult our official website. We will serve you wholeheartedly.