5A26432H04西屋
一般來講,DCS慣常使用兩層網(wǎng)絡(luò)結(jié)構(gòu),一層為過程級網(wǎng)絡(luò),大部分DCS使用自己的總線協(xié)議,比如橫河的Modbus、西門子和ABB的Profibus、ABB的 CAN bus等,這些協(xié)議均建立在標(biāo)準(zhǔn)串口傳輸協(xié)議RS232或RS485協(xié)議的基礎(chǔ)上?,F(xiàn)場IO模塊,特別是模擬量的采樣數(shù)據(jù)(機器代碼,213/掃描周期)十分龐大,同時現(xiàn)場干擾因素較多,因此應(yīng)該采用數(shù)據(jù)吞吐量大、抗干擾能力強的網(wǎng)絡(luò)標(biāo)準(zhǔn)?;赗S485串口異步通訊方式的總線結(jié)構(gòu),符合現(xiàn)場通訊的要求。 
    IO的采樣數(shù)據(jù)經(jīng)CPU轉(zhuǎn)換后聯(lián)系人:鄭娟萍                                                                                          
聯(lián)系電話:0592-5173279                                                                       
公司傳真:0592-5165561
電子郵箱:3150816822@qq.com
Q  Q:  3150816822變?yōu)檎螖?shù)據(jù)或?qū)嵭螖?shù)據(jù),在操作級網(wǎng)絡(luò)(第二層網(wǎng)絡(luò))上傳輸。因此操作級網(wǎng)絡(luò)可以采用數(shù)據(jù)吞吐量適中、傳輸速度快、連接方便的網(wǎng)絡(luò)標(biāo)準(zhǔn),同時因操作級網(wǎng)絡(luò)一般布置在控制室內(nèi),對抗干擾的要求相對較低。因此采用標(biāo)準(zhǔn)以太網(wǎng)是最佳選擇。TCP/IP協(xié)議是一種標(biāo)準(zhǔn)以太網(wǎng)協(xié)議,一般我們采用100Mbit/s的通訊速度。
    PLC系統(tǒng)的工作任務(wù)相對簡單,因此需要傳輸?shù)臄?shù)據(jù)量一般不會太大,所以常見的PLC系統(tǒng)為一層網(wǎng)絡(luò)結(jié)構(gòu)。過程級網(wǎng)絡(luò)和操作級網(wǎng)絡(luò)要么合并在一起,要不過程級網(wǎng)絡(luò)簡化成模件之間的內(nèi)部連接。PLC不會或很少使用以太網(wǎng)。Wheaton Instruments Omnispense Pump 375000
Chemglas OptiCHEM Tempstir Digital Controller CG-2032-3
Applikon P140 motor, 0-2000 rpm, ± 1 rpm, For 1, 2 & 3 
VWR Lab Jack / Lift, 12" x 12" Surface, Excellent Condi
3M Smart Battery Charger BC-210 For Use With Breathe E
Leybold Inficon IG 3 Vacuum Gauge 850-200-G1
Parker Compumotor SX Series Microstep Drive SX57-83-E
Parker Compumotor SX Series Microstep Drive SX6-Drive
Wave Biotech 19" Instrument Rack With Air Pump, CO2 Con
USA MADE Detecto MS-30 lb Digital Scale 30 Lb x .1 oz
IKA RCT Basic S1 Hotplate / Stirrer Amb——310°C, 0-1100 
IKA RCT Basic S1 With ETS-D4 fuzzy Controller / Probe
VWR Galaxy 14D 18 Position Centrifuge (AKA Micro 1814) 
Murr Elektronik Power Supply 85794 10AMP 24V DC 208-520
VWR Printing Thermometer 61161-286 W 2 Probes, Case, Se
HP 3488A Switch / Control Unit, 44474A and 44470A Modul
Masterflex 7524-00 Microprocessor Pump Drive, 7518-12 P
Millipore ELSHPS001 Control, ELSHCH001 Cooling Plate, P
Topcon Laser Level LTS-3, Case, Laser, Laser Power Supp
Hamilton GASTIGHT Digital Syringe 5 μL New W Case, Cert
YSI Biovision 8500 Dissolved CO2 Process Monitor
VWR Scientific Digital Heatblock 13259-052 949036, w 2 
GE Healthcare Life Sciences Can-Optomux Gateway Board 
Superior Electric 236BT Powerstat Variable Transformer
3M Smart Battery Charger BC-210 For Use With Breathe E
Ritchie Full Range SuperEvac LCD Vacuum Gauge, UPC 6868
YSI 3