可靠接地时整个485线路的地线必须要有良好的接触，从而保证电压一致，因为在实际施工中，为了接线方便，将线剪成多段再连接，没有将屏蔽线作良好的连接，从而使得其地线分成了多段，电压不能保持一致，导致共模干扰。
电缆额定电压的选择●电缆的额定电压应适合于电缆系统的运行状况，用Uo/U（Um）KV表示。
Uo--电缆设计用的导体对地或金属屏蔽之间的额定工频电压；U--电缆设计用的导体间的额定工频电压；Um--设备可承受的“最高系统电压”的最大值。
1kV-35kV阻燃交联聚乙烯绝缘电力电缆产品标准：本产品按GB1270《额定电压35kV及以下铜芯、铝芯塑料绝缘电力电缆》标准生产，还可根据用户需要按国际电工委员会推荐标准IEC、英国标准、德国标准及美国标准生产。
Flame retardant cable, is refers to under specified test conditions, specimen was, after removed test of ignition, flame spread only in a limited range, residual sheep and burning in the finite cable to self extinguishing in the course of time. The fundamental characteristic is that it may burn out and not run in the case of fire, but it can spread fire. Generally speaking, in case of electric wire fire, it can be put in the local scope, not to produce spread, keep other kinds of equipment, avoid causing greater loss. The meaning of the flame retardant cable: under specified test conditions, samples were, in is removed after the fire, the spread of flame on the sample only in a limited range and the characteristic of self extinguishing, which has the ability of or delay the outbreak or spread of flame.
电缆允许的弯曲半径：对有铠装或铜带屏蔽结构的电缆应不小于电缆外径的12倍。
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。
本产品是阻燃类产品。
二、执行标准 MT818.《煤矿用阻燃通信电缆》及企业标准Q/JG。
低压断路器在正常的情况下起到接通和断开负荷电流，还可以具有过负荷和短路保护的功能。
那么对于配电变压器低压侧的断路器怎么去整定和选择呢？配电变压器低压侧总断路器的设置，断路器具有长延时、短延时和瞬时三段式电流保护，为了保证变压器的保护与出线回路的选择性的配合，通常配电变压器的低压侧进线断路器不宜设置瞬时保护。
下面一一介绍低压断路器三段式电流保护值的整定计算。
配电变压器低压侧断路器三段式电流保护值的整定计算1.1低压断路器长延时过电流脱扣器的整定电流低压断路器长延时过电流脱扣器的整定电流宜等于或者接近变压器低压侧的额定电流值。
耐高温F46计算机电缆属于电子计算机系统专用电缆之一，是现代化工业建设急需的配套产品，其广泛用于能源工业、冶金工业和石油化工业等厂矿企业和科研部门的电子计算机、仪器仪表、各种自动化检测设备和其它信息处理设备的信号传输和控制系统。
5、缆芯包带：用非吸湿性带绕包缆芯。
6、铝塑粘结综合合护套：（1）屏蔽：用0.30mm厚的双面涂塑铝带，纵包于缆芯包带之外，两边搭接大于6mm并粘合在一起，400对以上采用轧纹纵包。
（2）护套：黑色低密度聚乙烯7、识别和长度标记：电缆表面印有**性识别标记，标记间隔1米，标记内容有：型号、规格、厂名、商标、制造年份及计米。
PVC电力电缆VVVV22VVPVVR交联电力电缆YJVYJV22YJV32阻燃电缆ZRVVZRVV22RVVZ(ZRVVR)耐火电缆NHVVNHVV22控制电缆塑料控制电缆全称聚氯乙烯绝缘和护套控制电缆执行标准GB适用于交流额定电压750V及以下控制，监控回路及保护线路等场合使用的聚氯。
Flame-retardant audio cable; ZR - manufacuring HYA, ZR - HYAC, ZR - HYAT, ZR - HYA53, ZR - HYAT53, ZR - HYV, ZR - HYA23, ZR - HYAT23, ZR - HYA22, ZR - HYAT22 product description: our factory produced communication cable is suitable for the fixed overhead laying or buried in the city ZR - manufacuring HYA: copper solid polyolefin insulation flame retardant poly (tidal layer sheath duct ZR - HYAT: copper solid polyolefin insulation filling type flame retardant poly (tidal layer sheath duct ZR - HYAC: Copper solid polyolefin insulation messenger tidal level flame retardant polyethylene sheath duct ZR - HYA53: copper solid tidal polyolefin insulation layer polyethylene sheath gangsu belt sheathed flame-retardant polyethylene sheath duct ZR - HYAT53: copper solid polyolefin insulated filled type tidal sheath gangsu belt sheathed flame-retardant layer together sheath duct ZR - HYA22: copper solid tidal polyolefin insulation layer polyethylene sheath steel tape armoured flame retardant PVC sheathed in communication cable ZR - HYA23: Copper solid polyolefin insulation tidal to get together on flame retardant sheath steel tape armoured layer sheath duct ZR - HYAT22: copper solid polyolefin insulation filling type tidal layer polyethylene sheath steel tape armoured flame retardant PVC sheathed in communication cable ZR - HYAT23: copper solid polyolefin insulated filled type tidal to get together on flame retardant sheath steel tape armoured layer sheathed communication cable in the city
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.
矿用电力电缆具有以下列特性：（1）应能长期承受较高、甚至很高、极高的工作电压，电缆应具有非常优良的电气绝缘性能；（2）能传输很大的电流(几百甚至几千安培)，为此电缆应有良好的热老化性（耐热性）和散热性；（3）电缆应有多种结构的护层以保护绝缘层，适应各种不同敷设环境（地下、水中、沟管隧道）的需要；（4。
GB1208-2016《电流互感器》第5.2项中规定标准的电流互感器二次电流为1A和5A，优选值为5A，当传输距离较大时应选1A。
线路功耗降低线路功耗与通过电流平方成正比，二次电流为1A的电流互感器比5A减低功耗25倍，即1A的功耗仅为5A的4%。
表1电流互感器测量回路的功耗传输距离加大下相同负载下，二次电流为1A互感器的传输距离是5A的25倍，这样可避免5/1A中间互感器或选用大容量互感器。
表2不同额定容量时的传输距离电线截面积小大中型工厂，当仪表和电流互感器安装距离较远(45.5m)时，从表2可以看出，当选用510VA电流互感器时，线截面积经计算需4mm3；若选用12.5VA电流互感器，线截面仅需1mm2。
TRVV柔性电缆RVVT、RVVTP耐弯曲电缆RVVPTTRVV柔性电缆RVVT、RVVTP耐弯曲电缆RVVPT的详细介绍TRVV柔性电缆RVVT、RVVTP耐弯曲电缆RVVPT型号：TRVV连接与控制用柔性电缆，广泛应用于干燥或潮湿的室内，往复自由弯曲移动无强制拉力的拖链系统中。
根据双方协商规定的长度交货。
适用于交流额定电压250V或直流500V及以下铁路信号联锁、火警信号等各类电器仪表及自动装置的连接线。
目前大量使用于智能电表集中抄表信号传输。
RS232/RS-485通讯电缆信号线适用于EIARS-232/422通讯网络，是楼宇自控、工业控制网络、电力自动化等通讯网络的常用电缆型号。
The cross section of the control cable is generally no more than 10 square meters, and the power cable is mainly used to transport power, which is generally large. Due to the above all when it comes to the reason, the specifications of the power cable can generally larger, to 500 square feet (normal manufacturer can produce range), again big cross section of the general factory is relatively less, you can do and control cable section generally small, generally not more than 10 square, tell from some cable, power cable according to the demand of power grid more generally for 5 core, and control cable transmission control, some more, according to the terms of more than 61 core, but also can produce according to user requirements.
5、缆芯包带：用非吸湿性带绕包缆芯。
6、铝塑粘结综合合护套：（1）屏蔽：用0.30mm厚的双面涂塑铝带，纵包于缆芯包带之外，两边搭接大于6mm并粘合在一起，400对以上采用轧纹纵包。
（2）护套：黑色低密度聚乙烯7、识别和长度标记：电缆表面印有**性识别标记，标记间隔1米，标记内容有：型号、规格、厂名、商标、制造年份及计米。