电缆、电缆类型的选择 Choice of cable and cable type 一.导线材料选择电缆一般采用铝芯线。 One. Wire material selection cable is generally used in aluminum core. 下列场合应采用铜芯电缆及电缆： Copper core cable and cable should be used in the following situations: （1）需要确保长期运行中连线可靠的回路。如：重要电源，重要的操作回路二次回路，电机的励磁，移动设备的线路及剧烈振动场合的线路。 (1) ensure that the cable is reliably connected for a long time. For example: the important power supply, the important operation circuit secondary circuit, the excitation of the motor, the circuit of the mobile device and the circuit of the violent vibration. （2）对铝有严重腐蚀而对铜腐蚀轻微的场合。 (2) there is a serious corrosion of aluminum and a slight corrosion of copper. （3）爆炸危险环境或火灾危险环境有特殊要求者。 (3) there are special claimants in the hazardous environment of explosion or fire danger environment. （4）特别重要的公共建筑物 (4) important public buildings （5）高温设备 (5) high temperature equipment （6）应急系统，包括消防设施的线路。 (6) emergency systems, including the wiring of fire facilities. 此外，经全面技术经济分析确证宜用铜芯电缆及电缆的，如有高层建筑，大、中型计算机房的建筑，重要的公共建筑等以及国外工程和外资工程等适应国外要求者。 In addition, the comprehensive technical and economic analysis confirm appropriate USES copper core cable and cable, such as high-rise buildings, the construction of large and medium-sized computer room, important public buildings and so on, and adapt to the abroad such as overseas and foreign engineering requirement. 二.电缆芯数的选择 Two. The choice of the core number of the cable （1）电压1KV及以下的三相四线低压系统，若第四芯为PEN线时，应采用四芯 型电 缆而不得用三芯电缆加单芯电缆组合成的回路的方式。当PE线作为专用而与带 电导体N线分开时，则应用五芯型电缆。若无五芯型电缆时可用四芯电缆加单芯电缆电缆捆扎组合的方式；PE线也可利用电缆的护套，屏蔽层，铠装等金属外 护层等。分支单相回路带PE线时应采用三芯电缆。如果是三相三线制系统则采 用四芯电缆，第四芯为PE线。 补：(此段解说引入TN-S,TN-C-S解说) (1) voltage up to and including 1 kv low-voltage three-phase four-wire system, if the fourth core for PEN line, four core type electric cable should be adopted and shall not use three core cable with single core cable, loop way. A five-core cable is applied when the PE line is used as a special purpose and is separated from the electric conductor N line. If there is no five-core cable, the way to pack a single cable cable with a single cable cable; The PE line can also be used for the shield of cable, shielding layer, armor, etc. Three-core cable should be used when the branch single-phase circuit belt PE. If it is a three-phase three-wire system, four core cables are used, and the fourth is PE. A: (the introduction of tn-s, tn-c-s commentary.) (2) 3-35KV交流系统应采用三芯电缆. (2) the 3-35kv communication system should have three core cables. (3) 在水下或重要的较长线路中为避免或减少中间接头或单芯电缆比多芯电缆有较好的综合技术经济性时,可选用单芯电缆。但应注意用于交流系统的单芯电缆不 得采用钢带铠装，应采用经隔磁处理的钢丝铠装电缆。 (3) in a long line of underwater or important to avoid or reduce the middle joint or single core cable than multicore cable has good comprehensive technical economy, can choose single core cable. However, it is important to note that the single-core cable for the communication system should not be used for steel tape armor and should be used for wire armored cable with magnetic isolation.