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干扰源及干扰一般分类
影响PLC控制系统的干扰源与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；按噪声干扰模式不同，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）电压迭加所形成。共模电压有时较大，特别是采用隔离性能差的配电器供电室，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模件损坏率较高的主要原因），这种共模干扰可为直流、亦可为交流。差模干扰是指作用于信号两较间的干扰电压，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，这种直接叠加在信号上，直接影响测量与控制精度。
Ellipsys E4A Telecom Communications Signal Processor
Lanco LTX DVD/CD Replication/Duplication Molder Dryer
Applied Materials 0195-02636 Praxair Ampoule Bubbler
(NetApp) DECRU DATAFORT FC520 V2 Security Appliance
KAWASAKI ROBOT SLAVE CONTROLLER Applied 0190-12377
MKS Instrument VoDM Vapor on Demand Module VODMC33CR1BE
NEW AMAT VAT Pendulum Control Valve Series 650 DN 320
Kaw*i Slave Robot Contoller C61C-B002
MKS Instrument VoDM Vapor on Demand Module VODMC33CR1BE
ENI DCG-200Z DC Plasma Generator, AMAT 0190-11593
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Lion Precision Probe Driver Modules DMT20 & DMT20A
ENI DCG-200Z DC Plasma Generator, AMAT 0190-10114
Hitachi T-18SX StarBoard StarTablet Interactive Monitor
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SONY PFV-D100 DIGITAL VIDEO INTERFACE UNIT
CTI Cryogenics Cryopump 8116250G001 w/ On-Board P300
Intel Server SR9000MK4U Itanium 2 (Dual Core)533MHz,2GB
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Hitachi Short Throw Zoom SL-502 for Hitachi CP-X1200
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AXIOMTEK P1000-370 -10.4" TFT MONITOR / COMPUTER
Dell PowerEdge 1950 Xeon 3.0Ghz dcore Server w/Win 03
bonus + windows 2003 server DELL PERC 5/i SAS
SGI TP9100 Storage - Includes x12 146GB HD!!!!!!
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New Sensotec Honeywell Signal Conditioner + Load Cell
Sennheiser SZI1015 - 2W IR Slave Emitter / Medium Space
REICHERT Microstar IV - Model 410 Microscope
3M Thermofax Transparency Maker Model 45FGA
Dukane ImagePro 8761 DLP, Digital 3LCD Multi Projector
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HC Power Power One Power Source HC1511-1D
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APC 5000VA Step Down Transformer 208V - 110V â AP9621
Silicon graphics GE16 030-1398-002 Rev A
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AMX VPT-CP Handheld Wireless Color Touchscreen
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Panasonic AJ-HSP500 HD Serial-to-Parrallel Converter
Bogen CAM8PRO 2-CAHNNEL 8 Input LINE/MIC mixer w comp
NEW TDK TAS300 Load Port Power Supply
Lucent Avaya Definity TN2214 Digital Line 24P Card V4
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