超强的冗余功能,冗余与热备这是两种完全不同的技术,很多厂商完全混淆这两种概念误导客户,大多数冗余的故障切换时间都在uS级,这是严格的无缝切换,而热备则带有很多的软件特征,切换慢一点的如某公司的400系列某型大型PLC,需要数分钟之久。同时冗余也还有双通过双口RAM和通过串行通信等数种不同的实现方式,这里面带有着相当大的成本和性能不同,用户在选取时需要认真调研。
每一个DPU内均有一块实时数据库,实时数据库按站数和内外分成多块,每个站都用广播方式将自己的变量全量发送出去,同时每个站都会接收和更新其它站广播过来的全局变量,这样使每个站都可以实时的得到其它站的数据,从而使DCS可以很好的控制一个大系统。
DCS的控制器和HMI(人机界面)通常是合二为一的,这也比较适合大型过程控制的监控室,这使DCS更显示出浓厚的PC根源。
Tektronix WFM1125 HD Digital Waveform Vector Mon.
30-day warranty/14-day right of return
TEKTRONIX TSG 1001
TEKTRONIX VITS 200
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Tektronix VX4801 48CH Isolated Digital I/O Module *Wty
NEW TEKTRONIX VX4380 SUREPATH 256 CROSSPOINT MATRIX
Tektronix VX4610 SDH/SONET Generator/Receiver Module VX
Tektronix AVDC100 Audio to Video Delay Corrector
2 Pieces – Tested, Calibrated, 14-day right of return
TEKTRONIX TDS520 TDS 520 DIGITAL OSCILLOSCOPE 500MHZ
Tektronix 2465B 400MHz 4 Channel Analog Oscilloscope
One-day shipping available
TEKTRONIX P3420 NSFP P3420
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Tektronix P6248 1.5GHz Differential Probe Tested
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Tektronix 495P Spectrum Analyzer 0-1.8 GHz Tested OK!
Tektronix VX4356 DPDT RELAY SWITCHING NEW Old Stock
Tektronix VM700/1 Video Measurement Set, NTSC
calibrated with 14 day ROR
Tektronix SD-46 Optical to Electrical Converter 20 GHz
Tektronix DL-11 Delay Line (Reduced!)
Tektronix TDS520A Digital Oscilloscope w/ opt
Tektronix 495P Tek Spectrum Analyzer *Read Notes* Wrks
Sony Tektronix AFG310 Arbitrary Function Generator New
Includes Software and Manuals New In Box
TEKTRONIX TLS216 / TLS 216 OSCILLOSCOPE
Tektronix TLA7AA4 DS 8Mb 136Ch Logic Analyzer Module
One-day shipping available
TEKTRONIX 7854 OSCILLOSCOPE w/ Opt 2D + AMP + TIME BASE
4 Slot Module w/ Dual Trace 7A24 + 7A18 + 7B80 + 7B85
Tektronix TDS2014 Oscilloscope w/4 ea. NEW P2220 Probe
JUST CALIBRATED by TEKTRONIX on Mar-2011, CAL DUE 2012
Tektronix TekScope THS730A 200MHz Oscilloscope THS730
@CALIBRATED@SALE@200 MHz Scope/ DMM 1GS/s@90D Warranty@
Tektronix 2465A DM 350 MHz scope, NIST-certified
additional free NIST recalibration within one year
TEKTRONIX TDS340 DIGITAL OSCILLOSCOPE
Tektronix TDS 340A TDS340A digital scope, NISTcertified
additional free NIST recalibration within one year
TEKTRONIX SD-46 20 GHZ HEAD CSA803C 11801C ELECTRICAL
Tektronix 2465 DMS 300MHz analog oscilloscope
Tektronix WFM300A-10 Composite/Component Waveform Monit
Tektronix TSG-170A NTSC Television Generator
Tektronix P7240 4Ghz Probe ACCESSORIES #15 Tested
Tektronix P7240 4Ghz Probe Tested
Tektronix 1503C Metalic TDR Cable Tester & YT-1 Printer
TEKTRONIX ASG 140, AUDIO SIGNAL GENERATOR
Tektronix P6248 1.5GHz Differential Probe Tested
Tektronix 11402 Digitizing Oscilloscope
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Tektronic 11801C Digital Oscilloscope SD-22, SD-20 ***
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Expedited shipping available
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Tektronix SD46 DC-20GHz Optical – Electrical Converter
Calibrated, 30-day warranty/14-day right of return