在改进耐火层制造工艺和增加耐火层等方法的基础上又研制了A类耐火电缆，它能够在950℃～1000℃的火焰中和额定电压下耐受燃烧至少90min而电缆不被击穿（即3A保险丝不熔断）。
A类耐火电缆的耐火性能优于B类。
采用对绞、对屏、总屏（或三线组合、组屏蔽、组屏总屏）等结构形式，具有介质损耗小、传输传号能力强、抗干扰性能好等特点，能可靠地传输微弱的模拟信号，可广泛地应用于发电、冶金、石油、化工、轻纺等部门的检测和控制用计算机系统或自动化装置，以及一般的工业计算机上。
电缆端头必须使用防止水及其它腐蚀性材料的侵蚀，以防因水树引起绝缘层老化而导致击穿。
电缆的装卸必须使用吊车或叉车，禁止平运，平放，大型电缆安装时须使用放缆车，以免电缆受外力损伤或因人工拖动而擦伤。
电缆如因故不能及时敷设时，应将其放在干燥地方贮存，防止日光爆晒，电缆端头进水等。
Rated voltage up to and including 35 kv cross-linked polyethylene insulating power cable which cable long-term allowed working temperature of conductor: 90 ℃ or less (2) when the short circuit (the longest duration of no more than 5 s) cables, the highest working temperature: 250 ℃ (3) in the air for laying a. Single core cable in parallel at the center of the distance: 185 was and below 2 times of the cable diameter: 240 was and above for 90 MMB. Ambient temperature: 40 ℃ directly buried laying a. Single core cable, is not contact 2 times the diameter of the center distance of cable b. ambient temperature: 25 ℃ c. soil coefficient of thermal resistance: Buried depth: 0.7m
HYA553铜芯实心聚烯烃绝缘挡潮层聚乙烯护套单层纵包轧纹钢带铠装聚乙烯套市通信电缆HYAT553铜芯实心聚烯烃绝缘填充式挡潮层聚乙烯护套双层纵包轧纹钢带铠装聚乙烯套市内通信电缆ZRCHYA铜芯实心阻燃聚烯烃绝缘挡潮层聚乙烯护套单层纵包轧纹钢带铠装聚乙烯套市通信电缆传输音频、150。
向SMD48（双字）写入所希望的初始值（若写入0，则清除）。
向SMD52（双字）写入所希望的预置值。
为了捕获当前值（CV）等于预置值（PV）中断事件，编写中断子程序，并指定CV=PV中断事件（事件号13）调用该中断子程序。
为了捕获外部复位事件，编写中断子程序，并指定外部复位中断事件（事件号15）调用该中断子程序。
执行全局中断允许指令（ENI）来允许HSC1中断。
9.执行HSC指令，使S7--200对HSC1编程。
Fully polyvinyl chloride distribution cable and local cable HJVV HJVVP HPVV local cable HCJVV? 1. Product implementation: gb11327-89. 2. Purpose: for short distance transmission. 3. Product model, specification and scope: HPVV 0.4-0.8mm 5-400 is applicable to the beginning and end of the line and is used to connect the local telephone cable to the distribution box or distribution frame. HJVV HJVVP 0.4-0.8 mmmm5 core -200 core is used to connect the distribution frame to the switch or the internal devices of the switch (including rural telephone service). 4, using features: cable laying temperature below 5 ℃. The bending radius of the cable shall not be less than 20 times of the outer diameter of the cable.
9.电线重量:1.5平方约重2.2公斤,2.5约重3.3公斤,4平方约重4.8公斤,6平方约重6.8公斤,快递以实际重量为准,只供参考.电线火线为红色，零线可选颜色有：红、黄、蓝、绿、棕、白、黑、双色几种。
绝缘材料：高密度聚乙烯，绝缘线的颜色符合全色谱标准。
绝缘线对：二根不同颜色的绝缘线按不同的节距扭绞成对，采用规定的色谱组合以便识别。
缆芯结构：以25对为基本单位，超过25对的电缆按单位组合，每个单位用规定色谱的单位扎带绕扎，以便识别不同的单位。
MHYVR煤矿用聚乙烯绝缘聚氯乙烯护套通信软电缆用于矿场作普通信号传输,可移动使用。
MHYVP煤矿用聚乙烯绝缘编织屏蔽聚氯乙烯护套通信电缆用于电场干扰较大的场所作信号传输,使用于固定敷设。
MHYVRP煤矿用聚乙烯绝缘编织屏蔽聚氯乙烯护套通信软电缆用于电场干扰较大的场所作信号传输,电缆较柔软。
Video transmission usually adopts direct modulation technology and takes the form of baseband (about 8MHz bandwidth). The common transmission medium is coaxial cable. Coaxial cable is specially designed for transmitting video, and its loss, image distortion and image attenuation are all relatively small, which can well complete the task of transmitting video.
Soft core shielding control cable -KVVRP; ZR - KVVRP; ZRC - KVVRP; NH - KVVRP shielded twisted-pair RVSP RVSP shielded twisted-pair cable (shielded twisted-pair cable, shielded cable, shielding twisted-pair cable this product is fit for ac rated voltage up to and including 450/750 control, monitoring circuit and protection circuit, etc. Products use features: 1. The cable conductor long-term allowed working temperature is 70 ℃; 2. The cable temperature under installation should not below 0 ℃, allowed bending radius; The cable without armor layer should not be less than 6 times the outer diameter of the cable. The cable with armored layer or copper band shielding structure shall be no less than 12 times of the outer diameter of the cable, and the soft cable with shielded structure shall be no less than 6 times of the outer diameter of the cable. Instructions for ordering: 1. Product name, model, case number, and rated voltage shall be indicated when ordering; 2. Delivery length and time; 3. Other special re
三极管有三种工作状态，分别是放大、饱和、截止。
使用最多的是工作在放大状态。
NPN型三极管其两边各位一块N型半导体，中间为一块很薄的P型半导体。
这三个区域分别为发射区、集电区和基区，从三极管的三个区各引出一个电极，相应的称为发射极（E）、集电极（C）和基极（B）。
发射区和集电区都是N型半导体，发射区的掺杂浓度比集电区的掺杂浓度要高得多。
在几何尺寸上，集电区的面积比发射区的面积要大。
发射区和集电区是不对称的。
Organization code certificate: CCC certificate no. : 20030 business license registration number: 0917 registration certificate: 3744 remittance account number: 910001507 opening bank: liuguxian rural credit cooperative, dacheng county, hebei province
ZR-YJV32ZR-YJLV32ZR-YJV33ZR-YJLV33ZR-YJV42ZR-YJLV42ZR-YJV43ZR-YJLV43交联聚乙烯绝缘阻燃聚氯乙烯/聚乙烯护套钢丝铠装动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。