6ES7138-4CA60-0AB0 想要它来亿佳
逻辑关系图反映了控制过程中控制作用与被控对象的活动,也反应了输入与输出的关系。 3. 绘制电路图 绘制电路的目的,是把系统的输入输出所设计的地址和名称联系起来。这是很关键的一步。在绘制 PLC 的输入电路时,不仅要考虑到信号的连接点是否与命名一致,还要考虑到输入端的电压和电流是否合适,也要考虑到在特殊条件下运行的可靠性与稳定条件等问题。 在接地电阻方面,对plc也许要求不高,但对dcs要在几欧姆以下(通常在4欧姆以下)。模拟量隔离也是非常重要的。 相同i/o点数的系统,用plc比用dcs,其成本要低一些(大约能省40%左右)。plc没有操作站,它用的软件和硬件都是通用的,所以维护成本比dcs要低很多。如果被控对象主要是设备连锁、回路相对很少,采用plc较为合适。如果主要是模拟量控制、并且函数运算很多, 采用dcs。dcs在控制器、i/o板、通讯网络等的冗余方面,一些 运算、行业的特殊要求方面都要比plc好的多。plc由于采用通用监控软件,在设计企业的管理信息系统方面,要容易一些。
APPLIED MATERIALS 0020-22275
APPLIED MATERIALS 0020-22453
APPLIED MATERIALS 0020-22493
APPLIED MATERIALS 0020-22844
APPLIED MATERIALS 0020-22852
APPLIED MATERIALS 0020-23587
APPLIED MATERIALS 0020-24798
APPLIED MATERIALS 0020-31162
APPLIED MATERIALS 0020-31163
APPLIED MATERIALS 0020-31520
APPLIED MATERIALS 0020-31534
APPLIED MATERIALS 0020-32325
APPLIED MATERIALS 0020-32326
APPLIED MATERIALS 0020-33570
APPLIED MATERIALS 0020-34831
APPLIED MATERIALS 0020-40164
APPLIED MATERIALS 0020-41008
APPLIED MATERIALS 0020-42270
APPLIED MATERIALS 0020-70127
APPLIED MATERIALS 0020-76096
APPLIED MATERIALS 0020-76183
APPLIED MATERIALS 0020-89025
APPLIED MATERIALS 0020-95175
APPLIED MATERIALS 0021-06924
APPLIED MATERIALS 0021-09097
APPLIED MATERIALS 0021-09453
APPLIED MATERIALS 0021-10019
APPLIED MATERIALS 0021-20042
APPLIED MATERIALS 0021-35829
APPLIED MATERIALS 0040-01004
APPLIED MATERIALS 0040-09004
APPLIED MATERIALS 0040-09005
APPLIED MATERIALS 0040-33998
APPLIED MATERIALS 0040-39678
APPLIED MATERIALS 0040-39990
APPLIED MATERIALS 0090-35118
APPLIED MATERIALS 0090-70005
APPLIED MATERIALS 0100-00015
APPLIED MATERIALS 0100-00165
APPLIED MATERIALS 0100-09001
APPLIED MATERIALS 0100-09055
APPLIED MATERIALS 0100-09056
APPLIED MATERIALS 0100-09079
APPLIED MATERIALS 0100-09099
APPLIED MATERIALS 0100-09114
APPLIED MATERIALS 0100-09117
APPLIED MATERIALS 0100-09134
APPLIED MATERIALS 0100-09137
APPLIED MATERIALS 0100-09146
APPLIED MATERIALS 0100-09224
APPLIED MATERIALS 0100-20051
APPLIED MATERIALS 0140-09007
APPLIED MATERIALS 0140-09028
APPLIED MATERIALS 0140-09122
APPLIED MATERIALS 0140-09197
APPLIED MATERIALS 0140-09269
APPLIED MATERIALS 0140-20255
APPLIED MATERIALS 0140-21416
APPLIED MATERIALS 0150-09053
APPLIED MATERIALS 0150-09054
APPLIED MATERIALS 0150-09072
APPLIED MATERIALS 0150-09097
APPLIED MATERIALS 0150-09099
APPLIED MATERIALS 0150-09258
APPLIED MATERIALS 0150-09462
APPLIED MATERIALS 0150-09593
APPLIED MATERIALS 0150-09640
APPLIED MATERIALS 0150-09642
APPLIED MATERIALS 0150-09880
APPLIED MATERIALS 0150-20580
APPLIED MATERIALS 0150-21337
APPLIED MATERIALS 0150-75041
APPLIED MATERIALS 0150-75068
APPLIED MATERIALS 0150-76166
APPLIED MATERIALS 0190-09026
APPLIED MATERIALS 0190-20015
APPLIED MATERIALS 0190-70060
APPLIED MATERIALS 0190-70066
APPLIED MATERIALS 0190-76050
APPLIED MATERIALS 0200-00221
APPLIED MATERIALS 0200-00426
APPLIED MATERIALS 0200-00674
APPLIED MATERIALS 0200-09201
APPLIED MATERIALS 0200-09636
APPLIED MATERIALS 0200-10041
APPLIED MATERIALS 0200-10073
APPLIED MATERIALS 0200-10392
APPLIED MATERIALS 0200-18053
APPLIED MATERIALS 0200-35222
APPLIED MATERIALS 0226-31128
APPLIED MATERIALS 0226-97725
APPLIED MATERIALS 0242-13897
APPLIED MATERIALS 0270-20016
APPLIED MATERIALS 0270-20032
APPLIED MATERIALS 0270-20044
APPLIED MATERIALS 0270-20053
APPLIED MATERIALS 0270-20066
APPLIED MATERIALS 0270-20069
APPLIED MATERIALS 0270-20087
APPLIED MATERIALS 0520-01002
APPLIED MATERIALS 0620-02271
APPLIED MATERIALS 0680-01105
APPLIED MATERIALS 0690-01037
APPLIED MATERIALS 1010-01088