Low smoke and low halogen flame retardant control cables are suitable for the use of ac rated voltage 450/750v and below control, monitoring circuit and protection line with certain environmental protection requirements. Operating conditions (1) rated voltage U0/U is 450/750v; (2) the cable conductor allowed to work at 70 ℃ for a long time; (3) the cable temperature under installation should not below 0 ℃, allowed bending radius; recommended by (4) the cable without armor layer shall be no less than 6 times the outer diameter of the cable; (5) the cable with armored or copper belt shielding structure shall be no less than 12 times the outer diameter of the cable; (6) the soft cable with shield layer structure shall be no less than 6 times of the cable. Technical requirements for 20 ℃ dc resistance conductors shall comply with the terms of GB9330.1 insulation resistance are shown in table 3 - table 6. The fire retardant performance test of the cable conforms to the provisions of GB/T18380. If the user does not require it to meet the requirements of class C fire retardant. The cable smoke concentration shall comply with the provisions of GB/T17651, and its light transmittance shall be 60%. The halogen content should not exceed 100 mg/g. Other performance requirements are the same as GB9330.
特种电缆就是有特殊用途、可以在特定场合使用的电缆,比如可以耐高温,耐酸碱,防白蚁,以及在轮船飞机核电站等场合使用的电线电缆。
就分类来说,它与电力、控制、计算机电缆等类别不属于同一种分类方法,也就是上列电缆中也包含有特种电缆在内。
一般特种电缆都需要制定企业内控标准。
航空航天、机车车辆、能源、钢铁、有色金属冶炼、石油开采、电机、建设等领域需用耐高温电线电缆。
长期连续工作温度135度、180度、250度及
有强电与弱电之分,这里介绍一种强电用低感电缆。
此电缆带有热耗散装置,用于各类接触焊机、电弧焊机与气动焊钳间相连接的新型水冷式低感电缆,具有结构简单合理、冷却水流通量大、不会形成堵塞阻断和限流现象、散热效果好、使用寿命长等特点。
SYV视频线、SYWV电视天线、RVVP屏蔽线、RVV护套线、AVVR多芯信号线、多芯音频线、RVSP双绞屏蔽线、各种屏蔽线缆、各种护套电源线、五类网络线、超五类网线、同轴电缆、各种监控线缆、各种弱电线缆 、各种高压电缆、各种射频、视频、同轴电缆、多芯视频电缆、多芯音频线、各规格、音响线、各种话筒线。
Development of low-smoke halogen-free cable technology: market technology status and development trend of low-smoke halogen-free flame-retardant cable materials
针对一套电气施工图,一般应先按以下顺序阅读,再对某部分内容进行重点识读1)看标题栏及图纸目录了解工程名称、项目内容、设计日期及图纸内容、数量等。
2)看设计说明了解工程概况、设计依据等,了解图纸中未能表达清楚的各有关事项。
3)看设备材料表了解工程中所使用的设备、材料的型号、规格和数量。
4)看系统图了解系统基本组成,主要电气设备、元件之间的连接关系以及它们的规格、型号、参数等,掌握该系统的组成概况。
25-50V、电流在“梅花芯“轮心“辐条