描述
一般来说，PLC是极其可靠的设备，出故障率很低。PLC的CPU等硬件损坏或软件运行出错的概率几乎为零；PLC输入点如不是强电入侵所致，几乎也不会损坏；PLC输出继电器的常开点，若不是外围负载短路或设计不合理，负载电流超出额定范围，触点的寿命也很长。
因此，我们查找电气故障点，重点要放在PLC的外围电气元件上，不要总是怀疑PLC硬件或程序有问题，这对快速维修好故障设备、快速恢复生产是十分重要的，因此笔者所谈的PLC控制回路的电气故障检修，重点不在PLC本身，而是PLC所控制回路中的外围电气元件。
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Netapp X1035B-R5 X1035B X1035 DUAL PORT GBE
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Netapp X1033A-R5 2-PORT, FCP ADAPTER II (111-00018)
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NetApp 320GB 5400 RPM HDD X266 A SP 266 for DS14 MK2 AT
NetApp X3145A NVRAM5 w/ 512MB Memory Battery 111-00022
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NetApp X2023C ULTRA 160 Dual Channel LVD SCSI 111-00024
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NetApp Emulex LP10000 2GB Single Port Fiber Channel HBA
NetApp X276A-R5 300GB 10K FC Disk for DS14Mk2 Shelf
NetApp X881-R6 Console Serial Cable Adapter (RJ45-DB9)
NetApp X1037B Dual Port GB Ethernet Controller
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NetApp X2050A Fiber Channel FC-AL Storage Controller
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