Installation requirements for cable trays
(1) When the trough type large-span cable tray enters the building from the outside, the outward slope of the tray shall not be less than 1/100.
(2) When the cable tray intersects with electrical equipment, the clear distance between them shall not be less than 0.5m.
(3) When two sets of cable trays are laid parallel at the same height, the clear distance between them should not be less than 0.6m.
(4) When drawing the route of the bridge on a parallel diagram, the coordinates or positioning scales and elevations of the starting point, ending point, turning point, branching point, and lifting point of the bridge should be indicated. If a cable tray laying axis side diagram can be made, the data calculation will be more accurate. Straight line segment: indicate the total length, number of bridge layers, elevation, type, and standard. Turning and branching points: indicate the type and standard of the turning joint used. Elevating section: indicate the change in elevation, which can also be indicated by partial detailed drawings or sectional drawings.
(5) When drawing the route of the bridge on a parallel diagram, the coordinates or positioning scales and elevations of the starting point, ending point, turning point, branching point, and lifting point of the bridge should be indicated. If a cable tray laying axis side diagram can be made, the data calculation will be more accurate. Straight line segment: indicate the total length, number of bridge layers, elevation, type, and standard. Turning and branching points: indicate the type and standard of the turning joint used. Elevating section: indicate the change in elevation, which can also be indicated by partial detailed drawings or sectional drawings.
(6) Generally speaking, for a large number of cable leads, straight bending plates and straight lead frames can be used, and for a few cable leads, guide plates or lead pipes can be used, indicating the lead method.
(7) The cable tray should be at least 2.2 meters above the ground, with the top of the tray no less than 0.3 meters away from the ceiling or other obstacles. The width of the tray should not be less than 0.1 meters, and the filling rate of the cross-section inside the tray should not exceed 50%.
(8) When the cables are laid straight in the cable tray, they should be fixed on the brackets of the tray at the upper end and every 1.5 meters. When laid horizontally, they should be fixed at the beginning, end, turn, and every 3-5 meters.
(9) When setting up in the ceiling, the open surface of the trough cover should maintain a straight clearance of 80 millimeters, and the utilization rate of the trough section should not exceed 50%
(10) The cables laid in the cable trough should not be tied, and the cables inside the trough should be straight and not inserted as much as possible. The cables should not overflow the trough, and should be tied and fixed at the entry and exit of the cable trough and at the turning points. The straight line groove cable should be fixed on the cable bracket every 1.5 meters.
(11) When laying wires in horizontal, straight cable trays and pen straight grooves, the cables should be tied. 4-pair cables should be bundled with 24 cables, and 25 or more pairs of backbone cables, optical cables, and other signal cables should be bundled and tied according to the type, diameter, and number of cable cores. The binding distance should not exceed 1.5 meters, the fastening distance should be uniform, and the tightness should be moderate.
(12) When laying cable trays horizontally, the support distance is generally 1.5-3m, and when laying straight, the distance fixed to the building structure should be less than 2m. The selection and laying standards for cable tray types and types.
(13) It is necessary to use steel or non combustible and flame-retardant materials for the fire-resistant section of the bridge.
