现场非常常见的怪事：桥架横平竖直、支架也密，结果电缆一放进去，盖板扣不上、转弯处磨破皮。问题不在桥架差，在“线比架子先到”。

The most common strange thing on site is that the cable tray is horizontal and vertical, and the brackets are also dense. As a result, once the cable is put in, the cover plate cannot be fastened and the skin is worn at the turning point. The problem is not with the bridge structure, it's with 'the line arrives before the frame'.

先算填充率，别凭感觉。动力电缆占桥架内截面积不超过40%，控制电缆不超过50%，再给自己留15%到20%的扩容余量。今天把空间用到90%，明年加一路监控或充电桩，只能再抱一根新桥架并行，成本翻倍。

Calculate the filling rate first, don't rely on intuition. The power cable accounts for no more than 40% of the cross-sectional area inside the bridge, the control cable accounts for no more than 50%, and there is also a 15% to 20% expansion margin left for oneself. Today we will use up 90% of the space, and next year we will add a monitoring or charging station. We can only hold a new bridge in parallel, doubling the cost.

强弱电别图省事放同一槽。实在同路，中间加金属隔板；信号线和动力线分层走，上层弱电、下层强电，避免变频器一开，PLC信号满屏跳点。

Strong and weak electricity diagrams are placed in the same slot to save time. If they are on the same path, add a metal partition in the middle; The signal line and power line are routed in layers, with weak electricity in the upper layer and strong electricity in the lower layer, to avoid PLC signal screen jumping points when the frequency converter is turned on.

转弯半径按非常粗那根电缆算。多芯电力电缆弯曲半径不小于12倍外径，控制电缆不小于6到10倍外径。很多“直角弯通”是现场用切割片自己拼的，拐角内侧直接把电缆绝缘顶白，半年后接地跳闸。

The turning radius is calculated based on the thickest cable. The bending radius of multi-core power cables shall not be less than 12 times the outer diameter, and the bending radius of control cables shall not be less than 6 to 10 times the outer diameter. Many "right angle bends" are made on site by cutting pieces themselves, and the insulation of the cable is directly white on the inside of the corner. After six months, the grounding trips.

出线口和垂直段加固定点。水平段每隔5到10米、垂直段每隔1到1.5米绑一道，不然电缆自重全压在拐角接头上，时间一长接头处护套开裂。

Reinforce the fixed points for the outlet and vertical section. Tie a cable every 5 to 10 meters in the horizontal section and every 1 to 1.5 meters in the vertical section, otherwise the cable's own weight will be fully compressed on the corner joint, and over time, the protective sheath at the joint will crack.

顺手一条运维习惯：每根电缆挂标签牌，起点终点、回路号、规格全写上。停电检修时，这一张牌比一个电工的记忆靠谱十倍。

A handy operation and maintenance habit: hang a label on each cable, and write down the starting and ending points, circuit numbers, and specifications. During power outage maintenance, this card is ten times more reliable than an electrician's memory.

把“填充留余量、强弱电分舱、弯半径按粗线算、垂直段勤固定”记在深化图里，桥架用十年都不会变成“第二根废线槽”。

Record the details in the detailed diagram, such as "filling with excess space, separating strong and weak electrical compartments, calculating bending radius according to thick lines, and fixing vertical sections frequently". The bridge frame will not become a "second waste wire trough" after ten years of use.