还可按电流制分为交流电缆和直流电缆。
按绝缘材料分1、以油浸纸作绝缘的电力电缆。
其应用历史最长。
它安全可靠，使用寿命长，价格低廉。
。
自从开发出不滴流浸纸绝缘后，解决了落差限制问题，使油浸纸绝缘电缆得以继续广泛应用。
3、技术指标：性能项目单位指标工作电容PF/m≤90电容不平衡PF/m≤1电感/电阻uH/Q≤25屏蔽抑制系数≤0.0120度时绝缘电阻≥5000试验电压V/1min2000阻燃特性（按照GB12666.5-90试验）A类4,产品型号及名称型号产品名称ZR-DJYP。
KYJVP铜芯聚氯乙烯绝缘聚氯乙烯护套控铜线编织屏蔽控制电缆。
KYJVRP铜芯聚氯乙烯绝缘聚氯乙烯护套控铜线编织屏蔽控制软电缆。
KYJVP2铜芯聚氯乙烯绝缘聚氯乙烯护套铜带屏蔽控制电缆。
KYJVRP2铜芯聚氯乙烯绝缘聚氯乙烯护套铜带屏蔽控制软电缆。
电焊机电缆本产品适用于二次侧对地电压交流不超过200V和脉动直流峰值400V电焊机用二次侧接线及连接电焊钳用。
在一定条件下，也可用于传输2048kbit/s及以上的数字信号。
HYA、HYAT用于架空、管道敷设。
This process specification provides for rated voltage 450/750v, single core 1.5-500mm2 PVC insulated or polyolefin insulated flame-retardant fire resistant soft cable; And 0.6/1kv single core 4~500mm2, 2~5 cores 1.5~240mm2 polychlorinated insulated or polyolefin insulated flame-retardant fire resistant flexible cables process specifications, technical requirements, and acceptance rules. The main models of this process specification are: rated voltage 450/750v: za-rv; WDZA - RY, etc. Rated voltage 0.6/1kv: za-rvv, za-rvv22, wdza-ryy, wdza-ryy23, wdna-ryy, wdna-ryy23. 2? Usage characteristics, classification and nomenclature of cables 2.1? Service characteristics 2.1.1 cable rated operating voltage: 450/750v, 600/1000v. 2.1.3 temperature under installation should not below 0 ℃. 2.1.4 small bending radius of cables: unarmored cables: the flame retardant type is 6 times the outer diameter of cables, and the fire resistant type is 12 times the outer diameter of cables; The armored cable is 20 times the outer diameter of the cable. 2.2? The cable type consists of 5 parts: serial code, insulation, sheath material code, outer sheath and performance code.
伏安法测量电阻的方法将待测电阻接上直流电源，用电压表和电流表分别测量电阻两端的电压和通过电阻的电流，再根据欧姆定律计算出被测电阻。
因为测量过程中需要借助电压表和电流表，伏安法是一种间接测量电阻的方法。
我们知道，电压表常常并联与电路中使用，电流表常常串联在电路中使用，都是可以带电操作的，故伏安法可以带电进行电阻的测量。
伏安法测量电阻的接线方式1）电压表前接电路：适用待测电阻很大（远大于电流表内阻）的情况。
???? In flame retardant series products, has been successfully used in the oxygen isolation technology, not only 0.6/1 kv polyvinyl chloride insulated and crosslinked polyethylene insulation flame retardant power cable can achieve GB/T12666.5 "into A bunch of power cable test" in class A, and rated voltage up to and including 6/10 kv 8.7/15 kv crosslinked poly (flame retardant power cable can reach A high class A demand and A large margin. On the basis of high flame retardant and high flame retardant cross-linked insulation, a low-smoke halogen-free high-flame retardant oxygen insulation layer power cable was added, and its low-smoke halogen-free performance was in line with GB/T17651.1.2 and GB/ t1765650.1.2. In this way, the overall level of the company's cross-linked power cable is lower than the domestic status. This company produces the type refractory power cables for rated voltage 0.6/1 kv copper core cable, can also produce low smoke zero halogen fire-resistant power cable, high flame retardant fire-resistant power cable oxygen insulation layer, the fire-resistant performance in line with the GB/T12666.6 cable fire resistance test. Therefore, the overall performance of refractory series power cables is good and reliable. The water resistance performance of fireproof cable conforms to iec 502-2.
耐火机理在矿用电缆的绝缘和护套材料中加入某种添加剂，降低聚合物产生的热量，防止聚合物分解或促进绝缘和护套材料炭化形成保护层；在线芯处增加一层云母玻璃丝带等无机绝缘材料，在绝缘和护套层被火燃蚀后，*缠包在导体上的云母耐火带保护而继续通电，从而在着火时保持一定时间的正常运行。
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，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。
Our factory was founded in 1971, is a production and sales of various kinds of flame retardant communication cable, shielded cable for mine, mine screen communication cable, mine telephone cable, shielded cable for mine, mine fire retardant cable, flame retardant cable, mining flame-retardant control cable, communication cable, mining cable, flame retardant mining communication cable, communication cable, mine cable, mine, mine control cable, cable for mine monitoring, sensors, cable, cable, control cable, computer cable, flame retardant cable, shielded cable. City communication cable, railway cable, power line, electrical equipment wire and cable, video line, special cable. And other professional manufacturers. Enterprises with more than 300 employees, engineering and technical personnel more than 30 people, the factory goes to 20000 square meters, owns fixed assets of 15 million yuan, the total number of companies have production and inspection equipment more than 120 units (pieces), annual output value of 150 million yuan.
ia-K2YV(EX)本安型PE绝缘、PVC护套二芯绞合屏蔽仪用电缆固定敷设在室内、电缆沟或管道中ia-K2YV(EX)R本安型PE绝缘PVC护套二芯绞合屏蔽仪用软电缆适用于要求柔软的场合ia-K3YV本安型PE绝缘PVC护套三芯绞合屏蔽控制电缆适用于要求柔软的场合ia-K3YVY本安。
Spin cassette XF5-273 communication cable transfer box, adopting advanced technology at home and abroad, in accordance with the international advanced standard production in the eighty s of cable wiring equipment, for the city, the town of telecommunication network backbone cable and wiring cable transfer. Features: 1. The connection jumper adopts rotary clamp-type connection and is sealed with silica gel on the metal clip, because it is not only reliable and durable, but also easy to operate and repair without stripping. 2. The wiring terminals in the handover box shall be arranged in 25 pairs as a basic unit, consistent with the basic units of the local telephone cables and marked with Numbers on the terminals to facilitate construction and maintenance. 3. The structure, arrangement and installation dimensions of the wiring modules are exactly the same as those of 3M products and can be used for each other. 4. The box body is treated by electrostatic spraying, beautiful and generous, with clear lines, good anti-corrosion and waterproof performance and long service life. Main technical parameters: the environment temperature: - 40 ℃ ~ + 65 ℃ atmospheric pressure: 70 ~ 106 kpa relative humidity: 95% or less is random ends and insulation resistance between terminals and ground > 5 x 104 Μ Ω. When connecting any two ends and any terminals and grounding to 1000V ac, there shall be no breakdown or flying arc in 1min. Contact resistance between wire and terminal < 5 x lO - 3 Ω.
例发动机组控制系统设计——使用多重背景设某发动机组由1台汽油发动机和1台柴油发动机组成，现要求用plc控制发动机组，使各台发动机的转速稳定在设定的速度上，并控制散热风扇的启动和延时关闭。
每台发动机均设置一个启动按钮和一个停止按钮。
项目的编程步骤如下：创建S7项目。
使用菜单“文件”à“新建工程”向导创建发动机组控制系统的S7项目，并命名为“多重背景”。
CPU选择CPU315-2DP，项目包含组织块OB1。
阻燃电缆阻燃电缆，是指在规定试验条件下，试样被燃烧，在撤去试验火源后，火焰的蔓延仅在限定范围内，残焰或残灼在限定时间内能自行熄灭的电缆。
根本特性是：在火灾情况下有可能被烧坏而不能运行，但可阻止火势的蔓延。
Crane or forklift should be used for the loading and unloading of cables. It is forbidden to run flat or lay flat. For installation of large cables, cable laying cart should be used to avoid external damage or abrasion caused by manual dragging. If the cable cannot be laid in time for some reason, it should be stored in a dry place to prevent sunlight from exploding and water entering the end of the cable. Note: the installation of wire and cable should be familiar with the performance of wire and cable installation personnel or full-time technical personnel, if there are still unclear matters, ball related technical department or technical department of our factory.