(2)耐火电缆大多用作应急电源的供电回路，要求火灾时正常工作。
由于火灾时环境温度急剧上升，为保证线路的输送，降低压降，对于供电线路较长且严格限定允许电压降的回路，应将耐火电缆截面至少放大一档。
(3)耐火电缆不能当作耐高温电缆使用。
⑥跑道中线灯。
以15或30m的间距装在跑道中线上，发出白色光线（接近跑道末端的为红色），标志跑道中线。
⑦接地带灯。
对称地装在跑道着陆端900m长的跑道道面内,共180个,发出白光,标志可以降落着地的地带。
6：产品性能和参数：导体结构：由7/1.04mm软铜线绞合而成绝缘：绝缘采用交联聚乙烯，绝缘厚度1.0mm，绝缘电阻可以保证在10000MΩ/km以上。
护套：绝缘采用低密度聚乙烯黑色护套，护套厚度1.8mm,从而保证了电缆优良的绝缘性能，防水性能和防老化性能。
1. Rated voltage U0/U: 0.6/1kv. 2. The long term allowable high temperature of the cable conductor is +90 degrees, and the short circuit high temperature is +250 degrees. 3. Installation and laying temperature: greater than or equal to 0 degrees, and the fixed dressing temperature is lower than -10 degrees. 4. The allowable small bending radius of the cable is greater than or equal to 15D(d-cable outer diameter).
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.
先看正向起动，合上QS，按下正向起动按钮SB1，KM1线圈得电使接触器KM1主触点吸合，电动机得电正向动转，此的电动机工作的电源相序为LLL3。
接触器KM1吸合的也断开了电路中的常闭触点KM1，这就断开了反向起动按钮的SB2的通路，这是按下SB2，KM2也不会吸合。
再分析一下反转的工作原理，合上QS，按下SB2，KM2线圈得电使接触器KM2吸合，这时电动机工作的电源就是把L1和L3颠倒了，相序成了LLL1了，电动机就得朝另一个方向运行了。
如采用75－9同轴电缆时，摄像机和监视器间的距离在500m以内可不加电缆补偿器。
HYA通信电缆，HYA22HYA23铠装通信电缆用途：实心绝缘填充型电缆适用于本地电信网的城市与乡镇电信线路，也适用于接入公用网的专用网线路。
A-DJVPV IA-DJYPV IA-DJYJPV 本安型、编织分对屏蔽（铜丝或镀锡丝）。
IA-DJVP2V IA-DJYP2V IA-DJYJP2V 本安型、铜塑复合膜分对屏蔽。
IA-DJVP3V IA-DJYP3V IA-DJYJP3V 本安型、铝塑复合膜分对屏蔽 。
HYV主要用于语音信号传输。
结构：导线：实心退火铜线。
铜线直径为：0.4，0.5，0.6，0.7mm。
绝缘：高密度聚乙烯，并按照全色谱标准标明绝缘线的颜色绝缘线对：把单根绝缘线按照不同的节距扭绞成对，以最大限度减少串音，并采用规定的色谱组合以便识别线对。
ZR-BPGGPP2硅橡胶绝缘和护套铜丝编织铜带绕包屏蔽耐高温变频电力电缆。
ZR-BPGGP3硅橡胶绝缘和护套铝聚酯复合膜绕包屏蔽耐高温变频电力电缆。
ZR-BPGVFP硅橡胶绝缘丁腈护套铜丝编织屏蔽耐高温变频电力电缆。
ZR-KVVP阻燃聚氯乙烯绝缘，阻燃聚氯乙烯护套铜丝编织屏蔽控制电缆敷设在室内、电缆沟中、管道内及地下，具有防干扰能力ZR-KVVP阻燃聚氯乙烯绝缘，阻燃聚氯乙烯护套软控制电缆敷设在室内移动要求柔软等场合。
The outer conductor knitting is usually 60%-80% suitable. The mould design and processing for insulation production are also key. It should ensure that the product reaches the ideal uniform structure and the e interface constant meets the design re
从另一方面看，同步方式要求进行信息传输的双方必须用同一个时钟进行协调，正是这个时钟确定了同步串行传输过程中每一个信息位的位置。
这样一来，如果采用同步方式，那么，在传输数据的还必须传输时钟信号。
而在异步方式下，接收方的时钟频率和发送方的时钟频率不必完全一样，而只要比较相近，即不超过一定的允许范围就行了。
在数据传输中，较为广泛采用的是异步通信，异步通信的标准数据格式如所示。
异步通信数据格式从所列格式可以看出，异步通信的特点是一个字符一个字符地传输，并且每个字符的传送总是以起始位开始，以停止位结束，字符之间没有固定的时间间隔要求。
Flame-retardant Cables: ibec60332-3 / bs4066-3 flame-retardant grades (BunchedWires or Cables vertical Flame On BunchedWires/Cables) this is a beam cable. According to the test regulations, the 3.5m long cable samples are fixed with iron wire on the trapezoid frame, and the number of samples is determined according to the non-metallic materials required for different classification. The sample is hung vertically on the back wall of the furnace and air is introduced into the furnace through the inlet on the bottom plate. At 750 ℃ flame propane plane and the sample, the sample in the compulsory blowing (5 m3 / min air emissions, wind speed 0.9 m/s), must be in vertical combustion is not up to 20 minutes, cable within 2.5 meters flame spread out on its own. IEC60332 is divided into A, B, C and D to evaluate the flame retardant performance.
对有屏蔽层结构的软电缆，应不小于电缆外径的6倍。
对无铠装层的电缆应不小于电缆外径的6倍。
MKVV煤矿用控制电缆、MKVVP煤矿用塑料控制电缆、MKVV22煤矿用塑料绝缘电缆执行标准：企标Q/TX本标准适用于煤矿用铜芯聚氯乙烯护套阻燃控制电缆。
充油通信电缆价格|充油通信电缆直径|充油通信电缆规格|充油通信电缆芯数充油通信电缆HYAT,HYAT53,（主要技术指标）电缆芯数（规格）电缆芯径直径绝缘最大偏心(mm)绝缘抗压缩力(N)绞合节距(mm)近端串音衰减远端串音防卫度备注HYAT5×2×0.40.4050..7-119.5。
Computer shielded cable; Purpose: high voltage insulation with small interface constant. Use to ground, and the screen, the total screen (or three quad twisted, group screening, group screen a total screen), such as structure form, with a small dielectric loss, the transmission ability is strong, resistant performance is good wait for a characteristic, can reliable transmission weak analog or digital, can be widely used in electricity, metallurgy, petroleum, chemical, textile sites detection and control of the door or by computer automation instrumentation, and general industrial computer. Relevant technical indicators: reference BS5308 IEC189 and British second, product code 1 and code the DJ - (series code) electronic computer shielded cable Y - (insulation code) high-pressure polyethylene F - (insulation code) fluoroplastic V - (sheath code) polyvinyl chloride (R - said many strands of soft wire core P - (block code) copper mesh shielding P1 tin plated copper mesh shielding P2 copper tape screened P3 aluminum-plastic composite membrane shielding for example 1:3, product specifications order 7 (14) to 1.0 was computer shielded cable can be represented as: (1) total shielding DJYVP7 * 2 * 1.0mm2 (2) partial shielding multiple strands of soft line DJYPVR7 * 2 * 1.0mm2 (3) total shielding type DJYPVP7 * 2 * 1.0mm2 Type (1) packet shielding DJYPV3 x 3 x 0.75 was (group 2) screen a total screen DJYPVP3 x 3 x 0.75 was three, model name and use range model name using range DJYVPDJYPVDJYPVP total shielding polyvinyl chloride polyethylene insulating sheath computer cable shielding polyvinyl chloride polyethylene insulation group sheathed electronic computer cable shielding total shielding polyvinyl chloride polyethylene insulation group sheathed electronic computer cable 1, fixed for laying indoors, in cable trench or pipe 2, cable long-term working temperature: - 20 ℃ + 65 ℃, the cable laying temperature is lower than 0 ℃, the bending radius should not less than 10 times of cable diameter DJYVPR DJYPVR DJYPVRP total shielding polyvinyl chloride polyethylene insulating sheath computer with a soft cable shielding polyvinyl chloride polyethylene insulation group sheathed computer with a soft cable shielding total shielding polyvinyl chloride polyethylene insulation group with a soft cable sheath computers shows that: (1) flame retardant cable (oxygen index greater than 30) need to add code "out" in front of the model. For example, zr-djypv zr-djypvp et al. (2) armored (steel belt armored) cables need to add code "22" in the lower right corner of the model, such as: DJYPV22 djypvpppvp22, etc. The cable is mainly used for ac or dc 300V or below and can work normally when 500V or below.