When installing parallel connection heating cables , pay attention to the position of two " cold ends " to ensure the heaters to be put at the positions needed to be heated . and core wires , heating threads and shiedlding layers can not touch each other in case of short circuit 安装并联带时，应注意二头“冷端”位置，确保带头发热段控制在需伴热的部位：并注意芯线、发热丝与屏蔽层相互之间不能触碰，以免短路。
A deformational particle with oil - soluable property is used as a bridge plug to build a shielding layer in the oil - gas reservior channel , to prevent the pollution caused by drilling mud entering the reservior due to the pressure difference , and so to protect the oil - gas reservior 摘要用一种具有油溶性质的可变形粒子做桥塞物，在油气储层通道中建立桥堵屏蔽层，防止由于压差造成钻井泥浆进入储层而形成污染，从而起到保护油气储层的作用。
Another is to design the unbalanced interconnect with one internal conductor to carry the " high " side of the signal , and a second one to carry the " low " , or " floating ground " side of the signal , plus a shield that surrounds them both and is tied to " ground " at one end of the cable only 其二，在非平衡连接中，用一个内部的导线传送“高端”的信号，同时第二个导线传输“低端”或“浮地”的信号，将这两股线用屏蔽层裹起来并且“只能"在线的一端进行接“地” 。
After electric heating system is installed , check electrical insulation of all circuits . the insulation resistance between generatrix and shielding layer , core wires of series cable before connection at end not be less than 20 m . and then check if dc resistance of circuit is normal and phase resistance is banlance 电伴热系统安装完工后，应逐路检查系统的绝缘电阻：各种电热带母线与屏蔽层之间、串联带芯线尾端末短接前的各芯线间绝缘电阻均应不小于20m ；然后再检查电热带直流电阻是否正常，三相电阻是否平衡。
Permissible min . bending radius : no less than 6 times of the completed cablediameter in case of unarmoured cable ; no less than 12 times of the completed cable diameter in case of armoured or copper tape screened cabel ; no less than 6 times of the completed cable diameter in case of screened flexible cabel 3电缆的允许弯曲半径：无铠装层的电缆，应不小于电缆外径的6倍；有铠装层或铜带屏蔽结构的电缆，应不小于电缆外径的12倍；有屏蔽层结构的软电缆，应不小于电缆外径的6倍。
In order to avoid gas blast because of short circuit , it should popularize shielded mine cable under coal mine . except insulated surface of part products adopting tinnint brass wires and nylon wires , its protective shield adopting conducting rubber and shielded layer which transition resistance not bigger than 3k . the protective layer adopt high machinery chloroprene rubber which is fireproof 为防止电缆相间短路而造成瓦斯气体爆炸，在煤矿井下应大力推广使用屏蔽矿用电缆，除部分产品的绝缘表面采用镀锡铜丝和尼丝交叉纺织之外，其外屏蔽型电缆的保护屏蔽采用导电橡皮及屏蔽层，其屏蔽层的过渡电阻不大于
It was difficult to measure the load voltage directly between inner and outer conductor of cable induced by shield current under low flux x ray . this paper introduces a measurement , pouring a current , which was same as cable approximately photocurrent in x ray test , into the shield of cable with a triocoaxial system , and the load voltage was got . finally the measured result of typical cable and comparison with the calculation was given with a special load 在简要介绍屏蔽电缆的转移阻抗和转移导纳耦合的基础上,描述了利用三同轴系统对双电缆和等效负载组成的电缆系统进行电流注入,模拟电缆屏蔽层发射电流,测量芯线等效负载感应信号的实验,给出实验结果及分析,并对理论结果与实验进行了比较。
For the improvement of reliability and stability of the whole apparatus , meanwhile , for eliminating various electric - magnetic disturbance within the power supply and ground , measures such as filter , grounding , shielding are all taken in technique . the special methods are lc filter for power supply , bypass capacitor for suppressing voltage surge in printed circuit board , shielding layer wrapped in sensor head and overall grounded 通过采用合理的滤波、接地、屏蔽等各种方法，尤其是采用电源lc滤波电路、电源上加旁路电容抑制线路板上的电压波动、传感头加屏蔽层、传感头总体接地结构等多种抗干扰办法，减小了电源和地线上的各种电磁干扰，保证了系统的稳定性和可靠性。
We adopt the positive temperature coefficient real core resistance wire as the heating body and xlpe insulator as the inner core to make the heating cable with pvc coating outside or hdpe sheath . metal screen heating cable has earth conductor and aluminum screen layer or copper web screen layer . the product has advanced tie - in technology and it is safe , reliable and convenience for operation . the performance indexes meet iec800 standard . 3 . technology indexes 本公司生产的发热电缆采用正温度系数实芯电阻线发热体，内芯采用xlpe绝缘，外包覆pvc或hdpe护套，屏蔽发热电缆具有接地导线和铝壳屏蔽层或铜网屏蔽层采用先进的接头工艺，施工安全可靠方便性能指标符合iec800标准要求。
