計(jì)算機(jī)及
網(wǎng)絡(luò)技術(shù)與控制系統(tǒng)的發(fā)展有著緊密的聯(lián)系。最早在50年代中后期，計(jì)算機(jī)就已經(jīng)被應(yīng)用到控制系統(tǒng)中。60年代初，出現(xiàn)了由計(jì)算機(jī)完全替代模擬控制的控制系統(tǒng)，被稱為直接數(shù)字控制（DirectDigitalControl,DDC）。70年代中期，隨著
微處理器的出現(xiàn)，
計(jì)算機(jī)控制系統(tǒng)進(jìn)入一個(gè)新的快速發(fā)展的時(shí)期，1975年世界上第一套以微處理為基礎(chǔ)的分散式計(jì)算機(jī)控制系統(tǒng)問(wèn)世，它以多臺(tái)微處理器共同
分散控制，并通過(guò)
數(shù)據(jù)通信網(wǎng)絡(luò)實(shí)現(xiàn)
集中管理，被稱為
集散控制系統(tǒng)（DistributedControlSystem,
DCS）。
進(jìn)入80年代以后，人們利用微處理器和一些外圍電路構(gòu)成了
數(shù)字式儀表以取代
模擬儀表，這種DDC的控制方式提高了系統(tǒng)的
控制精度和控制的靈活性，而且在多回路的巡回采樣及控制中具有傳統(tǒng)模擬儀表無(wú)法比擬的性能價(jià)格比。
為了克服DCS系統(tǒng)的技術(shù)瓶頸,進(jìn)一步滿足現(xiàn)場(chǎng)的需要,現(xiàn)場(chǎng)總線技術(shù)應(yīng)運(yùn)而生,它實(shí)際上是連接現(xiàn)場(chǎng)智能設(shè)備和自動(dòng)化控制設(shè)備的雙向串行、數(shù)字式、多節(jié)點(diǎn)通信網(wǎng)絡(luò),也被稱為現(xiàn)場(chǎng)底層設(shè)備控制網(wǎng)絡(luò)（INFRANET）。和Internet、Intranet等類型的信息網(wǎng)絡(luò)不同,控制網(wǎng)絡(luò)直接面向生產(chǎn)過(guò)程,因此要求很高的實(shí)時(shí)性、可靠性、資料完整性和可用性。為滿足這些特性,現(xiàn)場(chǎng)總線對(duì)標(biāo)準(zhǔn)的網(wǎng)絡(luò)協(xié)議作了簡(jiǎn)化,省略了一些中間層,只包括ISO/OSI7層模型中的3層：物理層、數(shù)據(jù)鏈路層和應(yīng)用層。
BENTLY NEVADA 18745-02 USPP 1874502
BENTLY NEVADA 3300/16-02-01-?02-00-00-00 USPP 33001602010200?00
BENTLY NEVADA 128240-01 NSPP 12824001
BENTLY NEVADA SNAPSHOT 2 44953-01
Bently after James Pollard 1828 LG Folio. The Birmingham Tally-Ho! Coaches
Enlarge
BENTLY NEVADA 30001-00-20-18?-02 NSPP 3000100201802
BENTLY NEVADA 300-00-00-32-1?8-02 NSPP 3000000321802
BENTLY NEVADA 3300/12-A01-B2?0-C00 USPP 330012A01B20C0?0
BENTLY NEVADA 3500/92 NSPP 350092
BENTLY NEVADA 330550-A06-B00 NSPP 330550A06B00
BENTLY NEVADA 30000-00-08-18?-02 NSPP 3000000081802
BENTLY NEVADA 30000-00-08-36?-02 NSPP 3000000083602
BENTLY NEVADA 30000-00-16-36?-02 NSPP 3000000163602
BENTLY NEVADA 30000-00-20-36?-02 NSPP 3000000203602
BENTLY NEVADA 30000-00-30-24?-02 NSPP 3000000302402
BENTLY NEVADA 76683-90 USPP 7668390
Bently Nevada 2201/02-02 System Monitor *GOOD PULL*
Designed for use in A/B 1771 I/O Racks
Bently Nevada 2201/03-03 4-Channel Monitor *GOOD PULL*
Designed for use in A/B 1771 I/O Racks
BENTLY NEVADA 4452-02 NSPP 445202
BENTLY NEVADA CA-90100-03-03?-06-03-02-01-0?1-02 USPP CA901000303060?30
BENTLY NEVADA 78462-01M USPP 7846201M
BENTLY NEVADA 90482-01 USPP 9048201
BENTLY NEVADA 170180-01-00 NSFP 1701800100
BENTLY NEVADA 170180-03-00 NSFP 1701800300
BENTLY NEVADA 3500/92 USPP 350092
BENTLY NEVADA 77589-01-90 NSPP 775890190
Bently Nevada Velocity Seismoprobe 16699-01-05-03 (5208)
BENTLY NEVADA 30000-00-38-36?-02 USPP 3000000383602
BENTLY NEVADA 30000-00-40-36?-02 USPP 3000000403602
BENTLY NEVADA 90225-22-02-01?-01-02-02-01-0?1-02 NSPP 90225220201010?2B
725500401, Bently Nevada Power Supply 7200 120VD Input
BENTLY NEVADA 79492-01 NSPP 7949201
BENTLY NEVADA 170180-01-00 NSPP 1701800100
BENTLY NEVADA 170180-02-00 NSPP 1701800200
BENTLY NEVADA 84140-01 NSPP 8414001
BENTLY NEVADA 90200-03-01-02?-02-01-01-02 USPP 90200030102020?10
BENTLY NEVADA 90200-22-03-01?-02-02-01-01-0?2 USPP 90200220301020?20
BENTLY NEVADA 90225-22-02-01?-01-02-02-01-0?1-00 USPP 90225220201010?20
BENTLY NEVADA 90225-22-02-01?-01-02-02-01-0?1-02 USPP 90225220201010?2B
BENTLY NEVADA 90225-22-04-06?-02-02-02-03-0?1-02 USPP 90225220406020?20
BENTLY NEVADA 90225-22-04-06?-02-02-02-03-0?3-04 USPP 90225220406020?2B
BENTLY NEVADA 90225-23-03-05?-01-02-02-03-0?1-02 USPP 90225230305010?20
BENTLY NEVADA 90225-23-03-05?-02-02-02-03-0?1-02 USPP 90225230305020?20
BENTLY NEVADA 90225-24-02-01?-01-02-02-01-0?2-03 USPP 90225240201010?20
BENTLY NEVADA PWA90482-01 USPP PWA9048201
BENTLY NEVADA 79492-01 USPP 7949201
BENTLY NEVADA 24134-02 NSPP 2413402
BENTLY NEVADA 3500/32 USPP 350032
BENTLY NEVADA 19000-00-07-36?-02 NSPP 1900000073602
BENTLY NEVADA 19000-00-20-36?-02 NSPP 1900000203602
NEW BENTLY NEVADA/GE 161957 PIM POWER INPUT MODULE SPARE SERIES 3300 PART 46498
BENTLY NEVADA 7200-RVXY-R USPP 7200RVXYR
BENTLY NEVADA 3300/10 USPP 330010
BENTLY NEVADA 21747-080-01 NSFP 2174708001
BENTLY NEVADA 72108-01-02 USPP 721080102
BENTLY NEVADA 72358-XX USPP 72358XX
BENTLY NEVADA 72836-01 USPP 7283601
BENTLY NEVADA 72869-02 USPP 7286902
BENTLY NEVADA 72870-01 USPP 7287001
BENTLY NEVADA 72870-03 USPP 7287003
BENTLY NEVADA 72870-53 USPP 7287053
BENTLY NEVADA 21504-00-40-10?-02 NSPP 2150400401002
BENTLY NEVADA CA-90125-02-03?-06-02-02-03-0?1-02 USPP CA901250203060?20
BENTLY NEVADA 19000-00-90-12?-02 USPP 1900000901202
NEW Bently Nevada 7200 Vibration Monitor Meter Card Assembly 72870-04
BENTLY NEVADA 21500-00-20-10?-02 NSPP 2150000201002
BENTLY NEVADA 21500-00-32-10?-02 NSPP 2150000321002
BENTLY NEVADA 21500-00-40-05?-02 NSPP 2150000400502
BENTLY NEVADA 21504-00-28-10?-02 NSPP 2150400281002
BENTLY NEVADA 21504-00-32-10?-02 NSPP 2150400321002
BENTLY NEVADA 21504-00-36-10?-02 NSPP 2150400361002
BENTLY NEVADA 21504-00-40-05?-02 NSPP 2150400400502
BENTLY NEVADA 21504-00-52-10?-02 NSPP 2150400521002
BENTLY NEVADA 21504-00-60-05?-02 NSPP 2150400600502
BENTLY NEVADA 21504-00-60-10?-02 NSPP 2150400601002
BENTLY NEVADA 21504-00-68-05?-02 NSPP 2150400680502
BENTLY NEVADA 21504-00-68-10?-02 NSPP 2150400681002
BENTLY NEVADA 72626-22 NSPP 7262622
BENTLY NEVADA 72608 NSPP 72608
BENTLY NEVADA 21504-00-08-05?-02 NSPP 2150400080502
Bently Nevada 72201-01-04-01?-01-01-15 VIBRATION & PROX
BENTLY NEVADA 16699-20-05-03 NSPP 16699200503
BENTLY NEVADA 7200-RVR USPP 7200RVR
BENTLY NEVADA 21504-24-64-05?02 NSPP 2150424640502
BENTLY NEVADA VELOCITY PROBE 330525 *NEW*
BENTLY NEVADA 7200-RVDP-R USPP 7200RVDPR
BENTLY NEVADA 21747-080-01 USPP 2174708001
BENTLY NEVADA 72208-02 USPP 7220802
BENTLY NEVADA 72308-01 USPP 7230801
BENTLY NEVADA 84143-01 USPP 8414301
BENTLY NEVADA 136188-01 USPP 13618801
BENTLY NEVADA 81545-01 NSPP 8154501
Bently Nevada 124534-01 Custom Proximitor
Dierks Bently Autographed Signed Guitar & PSA/DNA Proof UACC RD COA
Dierks Bently Autographed Signed Pearl Guitar & Proof PSA/DNA UACC RD COA
NEW Bently Nevada 3300 Proximitor Sensor 330100-50-05
2201/02-01 Bently Nevada for Allen Bradley PLC 5 N3
BENTLY NEVADA 72052-01 USPP 7205201
BENTLY NEVADA 72072-01 USPP 7207201
BENTLY NEVADA 82365-01 NSPP 8236501
BENTLY NEVADA 133300-01 USPP 13330001
Bently Nevada 72301-02-04-01?-01-01-15 PC Board
BENTLY NEVADA 20929-02 NSFP 2092902
BENTLY NEVADA 9002637-01 MONITOR SYSTEM SERIES 9000 PLC MODULE 53188
Bently Nevada 3500/60 Temperature Monitor 350060 Temp
BENTLY NEVADA 89968-0050-02-?01 NSPP 8996800500201
BENTLY NEVADA 330180-51-00 NSFP 3301805100
BENTLY NEVADA 33080-51-00 NSFP 330805100
BENTLY NEVADA 81545-01 USPP 8154501
BENTLY NEVADA 89590-01 USPP 8959001
BENTLY NEVADA PWA88199-01 USPP PWA8819901
BENTLY NEVADA VIBRATION MONITOR PROTECTION 1900/27 100 MV/G 20G PEAK 43265
BENTLY NEVADA 81723-00-50-90?-02 NSFP 8172300509002
BENTLY NEVADA 330900-50-00 NSFP 3309005000
BENTLY NEVADA 72358-51 USPP 7235851
BENTLY NEVADA 7200-DVTP-R USPP 7200DVTPR
BENTLY NEVADA 7200-EIPP USPP 7200EIPP
BENTLY NEVADA 82365-01 USPP 8236501
BENTLY NEVADA 82366-01 USPP 8236601
NIB Bently Nevada 3000 Series 300 Proximitor 20929-07
NIB Bently Nevada HIGH TEMP 25 MM Proximitor 24654-04
NNB Bently Nevada 200mv Proximitor 3109-300
BENTLY NEVADA 330102-00-60-1?0-02-01 NSFP 33010200601002
BENTLY NEVADA 330102-00-64-1?0-02-01 NSFP 33010200641002?01
BENTLY NEVADA 330102-00-72-1?0-02-01 NSFP 33010200721002?01
BENTLY NEVADA 81546-01 USPP 8154601
BENTLY NEVADA 21747-085-00 NSPP 2174708500
bently nevada 2201/02-02 MODULE SYSTEM MONITOR 1771 I/O
BENTLY NEVADA 330171-00-20-1?0-02-05 NSPP 33017100201002?05
BENTLY NEVADA 330171-00-08-0?5-02-05 NSPP 33017100080502?05
BENTLY NEVADA 330171-09-38-9?0-02-00 NSPP 33017109389002?00
BENTLY NEVADA 72053-01 USPP 7205301
BENTLY NEVADA 90478-01 USPP 9047801
BENTLY NEVADA 330100-90-00 USPP 3301009000
BENTLY NEVADA 3300/01 USPP 330001
BENTLY NEVADA 20929-01 USPP 2092901
1.00CT DIAMOND BAND RING. SIZE M. HALLMARKED. BROOKS & BENTLY
Returns: Accepted
Bently Nevada 124534-01 12453401 Custom Proximitor 24
BENTLY NEVADA 132306-02 NSPP 13230602
BENTLY NEVADA 21747-085-00 USPP 2174708500
BENTLY NEVADA 84157-01 USPP 8415701
BENTLY NEVADA 81544-01 NSPP 8154401
BENTLY NEVADA 330100-50-05 USPP 3301005005
BENTLY NEVADA 330100-90-05 USPP 3301009005
BENTLY NEVADA 84689-01 NSPP 8468901
BENTLY NEVADA 330100-50-02 USPP 3301005002
BENTLY NEVADA 16699 VELOCITY SEISMOPROBE VIBRATION SENSOR 500MV/IN/SEC 50585
BENTLY NEVADA 330101-00-08-0?5-02-01 NSFP 33010100080502?01
BENTLY NEVADA 126648-01 NSPP 12664801
BENTLY NEVADA 330102-00-16-0?5-02-00 NSFP 33010200160502?00
BENTLY NEVADA 133827-01 NSPP 13382701
BENTLY NEVADA 81546-01 SIGNAL INPUT RELAY CARD
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