电缆保护管是指为了防止电缆受到损伤，敷设在电缆外层，具有一定机械强度的金属保护管。电缆保护管主要安装在通讯电缆与电力线交叉的地段，防止电力线发生断线造成短路事故，引起通讯电缆和钢丝绳带电，以保护电缆、交换机、机芯板，以至整机不被烧坏，对电力线磁场干扰也起到一定的隔离作用。
Cable protective tube is a metal protective tube with certain mechanical strength laid on the outer layer of cable in order to prevent cable from being damaged. The cable protection tube is mainly installed at the intersection of communication cable and power line to prevent short-circuit accident caused by power line breaking, which leads to live communication cable and wire rope to protect cable, switch, core board, and even the whole machine from burning out. It also plays a certain isolation role in magnetic field interference of power line.