描述
继电器控制是通过元件之间的硬接线来实现的，因此其控制功能就固定在线路中了，因此功能专一，不灵活；而PLC控制是通过软件编程来解决的，只要程序改变，功能可跟着改变，控制很灵活。又因PLC是通过循环扫描工作的，不存在继电器控制线路中的联锁与互锁电路
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NETAPP X310_HSATET50SSM NA00 423.1GB X302A-R5 1TB SATA
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NetApp FAS940 Filer Head Network Appliance FAS 940
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Netapp X302A-R5 1TB SATA Drive for DS4243 108-00234
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LOT 2 NETAPP X266A X273B DRIVE/ TRAY 320GB 73GB 15K NEW
