点击图片查看原图
2711-T10C8
（5）来自接地系统混乱时的干扰接地是提高电子设备电磁兼容性（EMC）的有效手段之一。正确的接地，既能抑制电磁干扰的影响，又能抑制设备向外发出干扰；而错误的接地，反而会引入严重的干扰信号，使PLC系统将无法正常工作。PLC控制系统的地线包括系统地、屏蔽地、交流地和保护地等。接地系统混乱对PLC系统的干扰主要是各个接地点电位分布不均，不同接地点间存在地电位差，引起地环路电流，影响系统正常工作。例如电缆屏蔽层必须一点接地，如果电缆屏蔽层两端A、B都接地，就存在地电位差，有电流流过屏蔽层，当发生异常状态加雷击时，地线电流将更大。此外，屏蔽层、接地线和大地有可能构成闭合环路，在变化磁场的作用下，屏蔽层内有会出现感应电流，通过屏蔽层与芯线之间的耦合，干扰信号回路。若系统地与其它接地处理混乱，所产生的地环流可能在地线上产生不等电位分布，影响PLC内逻辑电路和模拟电路的正常工作。PLC工作的逻辑电压干扰容限较低，逻辑地电位的分布干扰容易影响PLC的逻辑运算和数据存储，造成数据混乱、程序跑飞或死机。模拟地电位的分布将导致测量精度下降，引起对信号测控的严重失真和误动作。AB 1756-IM16IAB 1746-IO12DCAB 1756-L55M14AB 1794-OB32PAB 1794-OB32PAB 1794-OB32PAB 1794-OB32PAB 1794-OB32PAB 1794-TB32AB 1794-TB32AB 1771-OFE2/BAB 1771-OW16/BAB 1771-IBD/BAB 1746-A4AB 1746-OB16AB 1746-OB16AB 1746-OB16AB 1746-OB16AB 1746-A7AB 1746-A7AB 1746-A7AB 1762-IQ16AB 1756-TBS6HAB 1756-TBS6HAB 1761-NET-ENIAB 1761-NET-ENIAB 1761-NET-ENIAB 1746-NT8AB 1746-NT8AB 1756-CPR2AB 1756-CPR2AB 1786-TPSAB 1786-TPSAB 1786-TPSAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1756-IR6IAB 1746-P2AB 1746-P2AB 1746-P2AB 1756-HSCAB 1756-HSCAB 1756-A4AB 1756-A4AB 1732DS-IB8XOBV4AB 1794-IE8AB 1794-IE8AB 1794-IE8AB 1794-IE8AB 1747-L532/EAB 1756-IB32AB 1756-IB32AB 1746-IM16AB 1746-IM16AB 1746-IM16AB 1746-IM16AB 1746-IM16AB 1746-IM16AB 1746-NI16IAB 1746-NI16IAB 1746-NI16IAB 1746-NI16IAB 1769-IR6AB 1769-IQ16AB 1769-IQ16AB 1769-IQ16AB 1769-IQ16AB 1769-IQ16AB 1769-IQ16AB 1769-IQ16AB 1769-IQ16AB 1769-IQ16AB 1769-IQ16AB 1747-L551/CAB 1747-L551/CAB 1747-L551/CAB 1756-CN2AB 1756-CN2AB 1756-DHRIO/CAB 1756-DHRIO/CAB 1756-DHRIO/CAB 1756-IA16AB 1756-IA16AB 1756-IF8HAB 1756-OB16IAB 1756-OB16IAB 1756-OB16IAB 1756-OB16IAB 1756-OB16IAB 1769-IF8AB 1769-IF8AB 1785-L40C15/FAB 1785-L40C15/FAB 1769-OF8VAB 1769-OF8VAB RB-7AB 1756-OF4AB 1756-OF4AB 1756-OF4AB 1756-OF4AB 1756-OF4AB 1756-OF6CIAB 1756-OF6CIAB 1756-OF6CIAB 1756-OF6CIAB 1756-OF6VIAB 1756-OF6VIAB 1756-OF8AB 1756-OF8AB 1756-OF8AB 1756-OV16EAB 1756-OV16EAB 1756-OW16IAB 1756-OW16IAB 1756-OW16IAB 1756-OW16IAB 1756-OW16IAB 1756-OW16IAB 1756-OW16IAB 1756-OX8IAB 1756-OX8IAB 1756-PA72/CAB 1756-PA72/CAB 1794-TB3AB 1794-TB3AB 1794-TB3AB 1794-TB3AB 1794-TB3AB 1794-TB3AB 1794-TB3TAB 1794-TB3TAB 1794-TBNAB 1794-TBNAB 188-K3B100AB 194R-1STNonCAB 194R-NE125-1753AB 22F-KF012-BSAB 2711P-RDT10CAB 2711P-RDT10CAB 500-CD920AB 800MR-HH2BLAAB 1747-L511AB 1756-A10AB 1756-A10AB 1747-L531/EAB 1747-L531/EAB 1747-L532/DAB 1747-L541/BAB 1747-L541/BAB 1746-NO4IAB 1746-NO4IAB 1746-NO4IAB 1746-NO4VAB 1746-NO4VAB 1746-NO4VAB 1746-NO4VAB 1746-NO4VAB 1746-OB16EAB 1746-OB16EAB 1746-OB32AB 1746-OV16AB 1756-CNB/EAB 1756-CNB/EAB 1756-CNB/EAB 1756-CNB/EAB 1756-CNBR/DAB 1756-CNBR/DAB 1756-CNBR/DAB 1756-CNBR/DAB 1756-CNBR/DAB 1756-CNBR/EAB 1756-CNBR/EAB 1756-CNBR/EAB 1756-CNBR/EAB 1756-CNBR/EAB 1756-CNBR/EAB 1756-CNBR/EAB 1756-CNBR/EAB 1756-CNBR/EAB 1756-DHRIOAB 1756-DHRIO/DAB 1756-DNB/AAB 1756-DNB/AAB 1756-DNB/AAB 1756-DNB/AAB 1756-DNB/AAB 1756-ENBTAB 1756-ENBTAB 1756-ENBTAB 1756-ENBTAB 1756-ENBTAB 1756-ENBTAB 1756-ENBTAB 1756-IA16IAB 1756-IB16AB 1756-IB16AB 1756-IB16AB 1756-IB16DAB 1756-IB16DAB 1756-IB16DAB 1756-IB16IAB 1756-IB16IAB 1756-IB16IAB 1756-IB16IAB 1756-IB16IAB 1756-IB16IAB 1756-IB16IAB 1756-A13AB 1756-A13AB 1756-A13AB 1756-A13AB 1756-A13AB 1756-A13AB 1756-A17AB 1756-CN2RXTAB 1756-DNB/DAB 1756-DNB/DAB 1756-DNB/DAB 1756-DNB/EAB 1756-DNB/EAB 1756-DNB/EAB 1756-DNB/EAB 1756-DNB/EAB 1756-EN2T/CAB 1746-A13AB 1746-BASAB 1746-HSCEAB 1746-HSCEAB 1746-HSCEAB 1746-HSCE2AB 1746-HSCE2AB 1746-HSCE2AB 1746-HSCE2AB 100-PTXN30AB 1492-IFM20D24AB 1492-IFM20FAB 1492-IFM40F-FS120-2AB 1734-ADNAB 1734-ADNAB 1734-OB8SAB 1734-OB8SAB 1734-SSIAB 1734-SSIAB 1746-IB32AB 1746-IB32AB 1746-IB32AB 1746-IV16AB 1746-IV16AB 1746-IV16AB 1746-IV16AB 1746-NI4AB 1746-NI8AB 1746-NI8AB 1746-NI8AB 1746-NIO4VAB 1746-NIO4VAB 1746-NIO4VAB 1746-IB16AB 1746-IB16AB 1746-IB16AB 1746-IB16AB 1746-IB16AB 1746-IB16AB 1746-IB16AB 1746-IB16AB 1746-IB16AB 1746-IB16AB 1747-L541/CAB 1747-L541/CAB 1747-L542/BAB 1747-L542/BAB 1747-L542/BAB 1747-L542/BAB 1747-L542/BAB 1747-L542/CAB 1747-L542/CAB 1747-L542/CAB 1747-L542/CAB 1747-L542/CAB 1747-L542/CAB 1747-L542/CAB 1747-L552/CAB 1747-L552/CAB 1747-L552/CAB 1747-M11AB 1747-M11AB 1747-M11AB 1747-M11AB 1747-M11AB 1747-M11AB 1747-M11AB 1747-M11AB 1747-M11AB 1747-M11AB 1746-OW16AB 1746-OW16c