产品规格: | 不限 | 产品数量: | 100.00 件 |
---|---|---|---|
包装说明: | 不限 | 价格说明: | 不限 |
查看人数: | 119 人 | 本页链接: | https://info.b2b168.com/s168-163875409.html |
品牌: | AB,ABB,GE |
IMMFP12 主要经销分散式控制系统(DCS)、可编程控制器(PLC)、工业机器人(配件)、数控系统模块、伺服控制系统组件以及其它工业产品和机电设备。优势品牌:A-B(ROCKWELL)、NATIONAL INSTRUMENTS(NI)、福克斯波罗(FOXBORO)、NI(National Instruments)、艾默生(Emerson)、博世力士乐(BoschRexroth)、罗斯蒙特(Rosemount)、通用(GE)、霍尼韦尔(Honeywell)、瑞恩(Reliance)、西屋(Westinghouse)、Schneider Modicon(施耐德莫迪康)等。同时,我们在很多地方都建立了高效和稳定的供应网络,如:德国,法国,加拿大,美国等地区。我们的产品应用于很多领域,包括设备制造工业,石油化工,动力工业,冶金工业,汽车制造业,航空**工业……等。 1.概述 随着科学技术的发展,PLC在工业控制中的应用越来越广泛。PLC控制系统的可靠性直接影响到工业企业的安全生产和经济运行,系统的抗干扰能力是关系到整个系统可靠运行的关键。自动化系统中所使用的各种类型PLC,有的是集中安装在控制室,有的是安装在生产现场和各电机设备上,它们大多处在强电电路和强电设备所形成的恶劣电磁环境中。要提高PLC控制系统可靠性,设计人员只有预先了解各种干扰才能有效保证系统可靠运行。 2.电磁干扰源及对系统的干扰是什么? 影响PLC控制系统的干扰源于一般影响工业控制设备的干扰源一样,大都产生在电流或电压剧烈变化的部位,这些电荷剧烈移动的部位就是噪声源,即干扰源。 干扰类型通常按干扰产生的原因、噪声的干扰模式和噪声的波形性质的不同划分。其中:按噪声产生的原因不同,分为放电噪声、浪涌噪声、高频振荡噪声等;按噪声的波形、性质不同,分为持续噪声、偶发噪声等;按声音干扰模式不同,分为共模干扰和差模干扰。共模干扰和差模干扰是一种比较常用的分类方法。共模干扰是信号对地面的电位差,主要由电网串入、地电位差及空间电磁辐射在信号线上感应的共态(同方向)电压送加所形成。共模电压有时较大,特别是采用隔离性能差的电器供电室,变送器输出信号的共模电压普遍较高,有的可高达130V以上。共模电压通过不对称电路可转换成差模电压,直接影响测控信号,造成元器件损坏(这就是一些系统I/O模件损坏率较高的原因),这种共模干扰可为直流、亦可为交流。差模干扰是指用于信号两较间得干扰电压,主要由空间电磁场在信号间耦合感应及由不平衡电路转换共模干扰所形成的电压,这种让直接叠加在信号上,直接影响测量与控制精度。 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS FANUC A20B-8200-0385 Tested in Good condition Pre-Owned 7 388 44 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS Pro-face AGP3300-L1-D24-M Tested in Good condition Pre-Owned 7 387 05 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS LS HMI XP70-TTA/AC ( XP70TTAAC ) New In Box Fast Ship Brand New 7 380 79 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS Fuji HAKKO V808CD V808CD Fast Ship Brand New 7 380 79 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS 122 Siemens servo axis cards 6SN1118-0DJ23-0AA2 Pre-Owned 7 379 40 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS New YOKOGAWA DCS CENTUM-XL with HDD Fast ship with warranty Brand New 7 374 54 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS New In Box Mitsubishi Servo Motor HC-MFS73BG1 Fast Ship Brand New 7 373 49 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS Mitsubishi servo motor HC-SFS352BG1H Tested in Good Condition Pre-Owned 7 371 27 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS WESTINGHOUSE 5X00376G01 Tested in Good condition Fast Ship Pre-Owned 7 368 21 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS New Mitsubishi servo motor HC-RP153BK Fast Ship Brand New 7 366 75 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS SIEMENS 6SN1121-0BA12-0AA0 6SN1 121-0BA12-0AA0 PLC Tested Pre-Owned 7 366 75 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS New Yaskawa CIMR-VBBA0010 Fast ship with warranty Brand New 7 366 20 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS YOKOGAWA DX11*A Tested in Good Condition Fast Ship Pre-Owned 7 365 92 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS METRONIX servo ARS-310/5 Tested in Good condition Pre-Owned 7 362 03 Free Shipping Watch From Hong Kong Get fast shipping and excellent service when you buy from e Top-rated sellers Item image 1PCS Siemens Touch Screen 6AV6545-0CA10-0AX0 6AV6 545-0CA10-0AX0 Tested 7 360 64
相关分类: 现场总线 特殊/专业电源 人机界面 机器视觉系统 混频器 电器元件 触控产品 变频器 保护器 EPS电源 DCS/PLC系统