Power cable installation considerations, characteristics and operation condition 1, power cable installation considerations for cable laying parallel with heat pipe installation to keep a distance of 2 m, when crossing, should keep 0.5 m. The cable shall be installed at a distance of 0.5m in parallel or across other pipelines. When the cable is directly buried and installed, the direct buried depth of 1-35kv cable is less than 0.7m. When 10KV and below cables are installed in parallel, the net distance between them shall not be less than 0.1m and 10-35kv shall not be less than 0.25m. The distance of cross installation is not less than 0.5m. Cable laying temperature lower than 0 ℃, bending radius: multi-core cable or 15 (D + D), a single cable 20 or more (D + D), (D for cable diameter, D) for the conductor diameter.
1、额定电压450/750v 2、电缆导体的长度允许工作温度为70摄氏度 3、电缆的敷设温度应不低于0摄氏度，推荐的允许弯曲半径； 4、无铠装层的电缆，应不小于电缆外径的6倍 5、有铠装或铜带屏蔽结构的电缆，应不小于电缆外径的12倍。
电缆地线芯绝缘采用具有抗氧化性能的K型B类低密度聚乙烯。聚乙烯的绝缘电阻高，耐电压好，介电系数小和介质损耗温度和变频率的影响也小，不但能满足传输性能的要求，而且能确保电缆的使用寿命。为了减少回路间的相互串扰和外部干扰，电缆采用屏蔽结构。
Armored communication cable mechanical protection layer: type 53 adopts 0.15mm thick corrugated steel belt, which is longitudinal wrapped on the basic cable and overlapped on both sides. The surface of the steel belt is coated with plastic to prevent corrosion and water intrusion.
HYV、HSYV室内大对数通信电缆介绍：程控交换局内总配线架与交换局用户之间的音频连接，也可用作其它通信设备之间的音频连接，可支持低速率的数据传输，支持语音应用、数字电话、传真、程控交换机、数字设备的连接、电讯综合系统的分支线和主干线等，内导体线径（mm）：0.40、0.50、0.60、0.70、0。
plc方式很多，有很多厂家是自己独有的，如施耐德的MB+；AB的DH+，CONTROLNET；西门子的PROFIBUS，MPI；还有很多通用的比如，RS23RS48以太网、GPRS等等。看你实际需要，来选择。信号线连接.这是一种最简单的方式,即在单片机或触摸屏等设备和PLC之间进行连接信号线,PLC的输入接单片机输出;PLC输出接单片机输入,这是一种最普遍的方式,通过这种方式PLC几乎可以和任何工控的控制装置连接,比如伺服系统,变频器,机器人等等!缺点是如果需要传递的信号太多,那么电缆数量也会很大,而且一旦电缆损坏,维护起来很困难!2.自由口通讯,以前我们多次讲到过自由口通讯，而且专门讲解过ASCII码，有需要的朋友可以去我以前的文章里去找，今天不重复了。
Ifthesheathismadefromothermaterial,issignifiedby“4”.Forexample,thebraidedsteelwirearmourfluoroplasticshe。
3．成品电缆经受交流50HZ3.5KV/5min电压试验不击穿。本质安全防爆测温系统用补偿导线或电缆采用低电容、低电感材料结构，具有防爆安全性能，适用于有爆炸危险的环境下作防爆热电偶冷短与防爆测温仪表连接，形成本安热电偶测温系统。
VV32VLV32VV33VLV33VV42VLV42VV43VLV43聚氯乙烯绝缘聚氯乙烯聚乙烯护套钢丝铠装电力电缆敷设在高落差地区，电缆能承受机械外力作用及相当的拉力。KVVKVVRKVYKVYR聚氯乙烯绝缘聚氯乙烯聚乙烯护套控制电缆敷设在室内、电缆沟、管道内及地下。
（配线用）HJVV、HJVVP、HPVV通信电缆介绍：用于配线架至交换机或交换机内部各级机器间连接等（包括农村电话局用），线路的始端和终端，供连接市内电话电缆至分线箱或配线架之用，内导体线径（mm）：0.40、0.50、0.60、0.70、0.80、0.90对数（对）：5—1000HPVV低频通信配。
(d)VV22型号比VV型号多加一套铁皮铠装。 (e)铠装后的结构更适合掩埋于地下。产品特性： (a)U0/U为0.6/1KV及以下。 (b)电缆导体的工作温度不大于70℃，短路时（最长持续时间不超过5s）电缆导体的最高温度不超过160℃。
四、电力电缆安装注意事项、使用特性及运行敷设条件1、电力电缆安装注意事项电缆与热力管道平行安装时保持2m的距离，交叉时应保持0.5m。电缆与其它管道平行或交叉安装时均要保持0.5m的距离。电缆直埋安装时，1-35KV电缆直埋深度不小于0.7m。
直角对管线的影响无论是管道还是电线，弯一个直角对材料本身寿命是有很大影响的。这一点在我们弯折管线后，观察折弯位置即可知道——弯折角度达到90°时，折弯位置就会发白。看起来是“发白”，实际上是外壁被拉伸变薄了。日后很容易发生漏水、漏电等情况。直角对维护的影响对于电路来说，还涉及到后期维护的问题——电路施工要求后期可以从穿线管内自由抽拉电线，也就是俗称的“活线”。但是当线路中的直角弯过多，势必会导致电线被卡在穿线管里，成了“死线”。
At present, with the continuous development of kejiping, the flame retardant problem has gone from halogen flame retardant in the past to low halogen and non-halogen flame retardant. Companies in the development and production "of" communication power supply with the antiflaming fire-resistant flexible cable, the cable insulation and sheath using the low smoke zero halogen, high decomposition temperature and good mechanical properties of halogen-free, polymer materials, due to cable contains no halide and metal oxide, in does not produce harmful gases, and a lot of smoke, there is no cause the possibility of "secondary disasters", and it also has good mechanical properties and electrical properties, the operating requirements of cable, completely changed the deficiency of past flame retardant cable.
Flame retardant cables and fireproof cables: the difference between the average person is very easy to confuse the concept of flame retardant cables and fireproof cables, although there are many more flame retardant cable applies to the advantages of chemical enterprise, such as low, low smoke, non-halogen, but in general, fire-resistant cable can replace flame retardant cable, and flame retardant cables can't take place of fire-resistant cable.