我们新研制出一种用于纸浆白度测定的智能白度仪，该仪表采用西门子公司生产的S7-224 CPU结合软件功能进行数据处理，具有较好的可靠性、重复性、精确度和稳定性。为了使其能与其它智能设备之间实现通信，我们将通过现场总线技术把它连接到网络中，使它成为造纸厂现场总线控制系统的一部分。

2.现场总线的选择

  2.1现场总线技术的选择

  现场总线集控制技术、计算机技术、通信技术于一体，是当今自动化领域技术发展的热点之一。这项技术可将多个智能控制仪表连接成网络系统，实现分布式计算机控制，提高检测和控制精度，改善系统的动态响应速度，提高系统安全性，从而得到了广泛的应用。

  近年来，几种有影响的现场总线技术已在一些特定的应用领域里显示出各自的优势。在此，我们选定了现为德国和欧洲标准的PROFIBUS（Process Fieldbus）现场总线。一方面由于它是目前数据传输率快的一种现场总线，传输率高可达12Mbps，另一方面它能够很好的与西门子的传动设备相配合，并与西门子PLC（Programmable Logic Controller）结合紧密且组态简便。

  2.2 PROFIBUS现场总线简介

  参照ISO/OSI参考模型,PROFIBUS现场总线只包含物理层、数据链路层和应用层。由PROFIBUS-DP，PROFIBUS-FMS， PROFIBUS-PA组成PROFIBUS系列。

  PROFIBUS-DP：经过优化的高速、廉价的通信连接，专为自动控制系统和设备级分散I/O之间通信设计，使用PROFIBUS-DP模块可取代价格昂贵的24V或0～20mA并行信号线。用于分布式控制系统的高速数据传输。

  PROFIBUS-FMS ：解决车间级通用性通信任务，提供大量的通信服务，完成中等传输速度的循环和非循环通信任务，用于纺织工业、楼宇自动化、电气传动、传感器和执行器、可编程序控制器、低压开关设备等一般自动化控制。

  PROFIBUS-PA专为过程自动化设计，标准的本质安全的传输技术，实现了IEC1158-2中规定的通信规程，用于对安全性要求高的场合及由总线供电的站点。

  本设计中采用的是PROFIBUS-DP标准，PROFIBUS-DP（或DP标准）是由欧洲标准EN50170定义的一种远程I/O通信协议。DP表示分布式外围设备，亦即远程I/O。PROFIBUS-DP还用到了应用层接口（ALI），ALI将过程对象转换为通信对象。

 NIB VEXTA C8384-9212H C83849212H STEPPING MOTOR 2 PHASE 1.8* / STEP 4.4A 2.5V
1 PC  VEXTA RKD514L-C servo drive Tested
1 PC Used AXHD15K VEXTA stepper driver
1 PC Used AXHD30K VEXTA stepper driver
1 PC Used VEXTA Dongfang Motor Vibration Damper D6CL-6.3F
1 PC Used Vexta Oriental Motor UDK5107N In Good Condition
1 PC Used Vexta PCB AXHD100K In Good Condition
1 PC Used Vexta UDK5114N In Good Condition
1 PC VEXTA RKD514L-C servo drive Tested
1 PC VEXTA Servo Drive RKD514L-A Tested
1 PC VEXTA Stepper Motor Driver RC-204A Tested
1 PCS   VEXTA stepper driver   CSD5814N   tested
1 PCS   VEXTA stepper driver  CSD2112-P   tested
1 PCS   VEXTA stepper driver  CSD2120-P   tested
1 PCS   VEXTA stepper driver  CSD2120P2   tested
1 PCS   VEXTA stepper driver  CSD5814N-P   tested
1 PCS   VEXTA stepper driver CMD2112P   tested
1 PCS   VEXTA stepper driver CSD5807N    tested
1 PCS   VEXTA stepper driver CSD5807N-P  tested
1 pcs  VEXTA   Motor SD5107P2  tested
1 pcs  VEXTA  Motor PK243A1-SG10  tested
1 pcs  VEXTA drive SD5107 board  Tested
1 PCS NEW IN BOX VEXTA Oriental Governor TMP-1
1 pcs used Dongfang VEXTA stepping motor driver 2-PHR5E DRIVER UD2115B
1 pcs VEXTA 2.8A CSD2120-P   stepper motor driver tested
1 pcs VEXTA 2.8A CSD2120-P stepper motor driver tested
1 pcs VEXTA CSD5807N-P 0.75A   stepper motor driver tested
1 pcs VEXTA CSD5807N-P 0.75A stepper motor driver tested
1 pcs VEXTA CSD5814N-P    stepper motor driver tested
1 pcs VEXTA CSD5814N-P stepper motor driver tested
1 pcs VEXTA drive SD5107 board Tested
1 PCS VEXTA five-phase stepper driver DFC5103P in good condition
1 PCS VEXTA five-phase stepper driver UDX5107N 0.75A 100V in good condition
1 pcs VEXTA Motor PK243A1-SG10 tested
1 pcs VEXTA Motor SD5107P2 tested
1 PCS VEXTA Oriental BLHD15K DC24V Brushless DC Motor Driver in good condition
1 PCS VEXTA Oriental driver AXHD15K in good condition
1 PCS VEXTA stepper driver CMD2112P tested
1 PCS VEXTA stepper driver CSD2109-P in good condition
1 PCS VEXTA stepper driver CSD2112-P tested
1 PCS VEXTA stepper driver CSD2120-P tested
1 PCS VEXTA stepper driver CSD2120P2 tested
1 PCS VEXTA stepper driver CSD5807N tested
1 PCS VEXTA stepper driver CSD5807N-P tested
1 PCS VEXTA stepper driver CSD5814N tested
1 PCS VEXTA stepper driver CSD5814N-P tested
1 product rating- C173376 Lot 4 Vexta PK266-01B 2-Phase 1.8°/Step Stepping Motor (DC1A, 7.4Ω)
1 product rating- GATES 3VX400 SUPER HC VEXTA POWERBAND BELT
1 product rating- ONE USED VEXTA PH265M-31
1 product rating- ONE Vexta 2-Phase Stepping Motor Model PK264-02A
1 product rating- Oriental Motor ASD18A-K Vexta AlphaStep Closed Loop Motor Driver
1 product rating- Oriental Motor ASD18A-K Vexta AlphaStep series Closed Loop Motor Driver
1 product rating- ORIENTAL MOTOR PH265M-31 / PH265M31 (USED TESTED CLEANED)
1 product rating- Oriental Motor PK264-02A Vexta Stepping Motor 2-Phase 2Amp 1.4Ω PK26402A
1 product rating- ORIENTAL MOTOR PK545-NB / PK545NB (USED TESTED CLEANED)
1 product rating- ORIENTAL MOTOR UDX5114N / UDX5114N (REPAIR EVALUATION ONLY)
1 product rating- ORIENTAL MOTOR VEXTA PK266-01B STEPPING MOTOR UNIPOLAR 2 PHASE
1 product rating- ORIENTAL VEXTA STEPPING MOTOR UNIT PK264-02A 2- PHASE DC 2A 1.8/STEP
1 product rating- Vexta (Oriental Motor Co.), Model PK266-01B, Stepping Motor, DC 1A, 7.4 Ohm
1 product rating- Vexta 2 Phase Stepping Motor - PH265M-31
1 product rating- Vexta 2 Phase Stepping Motor 1/8" Step PK266-01B
1 product rating- VEXTA 2phase Oriental stepper drive CSD2109-P
1 product rating- Vexta PH265M-31 2-Phase Stepping Motor, DC6V, 0.85A/Phase
1 product rating- VEXTA PH265M-31 Stepping Motor, 2 Phase 0.9 degrees Per Step 6 Volt DC
1 product rating- Vexta PK244PA 2-Phase Stepping Motor DC 1.2A
1 product rating- VEXTA PK266-01B Stepping Motor 2-Phase 1.8o/Step 1ADC 7.4Ohm PK266-01B *NEW*
1 product rating- Vexta Stepping Motor PK266-01B w/USDigital E3-2500-250-I-D-D-B Encoder
1 x Vexta PH266-02 2 Phase Stepping Stepper Motor 1.8 deg/step DC 6v  1.2 AMP
1 x Vexta PH266-02 2 Phase Stepping Stepper Motor 1.8 deg/step DC 6v 1.2 AMP
1.0 out of 5 stars.
182698 New-No Box, Oriental K0177-M Vexta Brushless DC Motor 60W, 2000r/min
193316 New-No Box, Vexta A5246-9412K Stepper Motor, 2 Phase, 2.1A
1Pair New VEXTA EIC4081 EIC4091 ZIP-15  #F4594 CY
1Pair New VEXTA EIC4081 EIC4091 ZIP-15 #F4594 CY
1Pair New VEXTA EIC4081 EIC4091 ZIP-15 #F4594 CY 
1PC   used Vexta 2-Phase Driver UDK2120 Tested
1PC  USED VEXTA MSP101 Driver
1pc  Used VEXTA MSP101 Driver Tested
1PC  Used VEXTA Oriental motor speed regulator SG8030J
1PC  Used VEXTA Oriental motor stepping PK566-NB
1PC NEW VEXTA  SBR11-ZP
1PC NEW vexta  SS22M-SSSD
1pc NEW VEXTA governor DSP501M
1PC NEW VEXTA SBR11-ZP
1PC NEW vexta SS22M-SSSD
1pc Omron Proximity Switch TL-N5ME2 10-30VDC 2M
1pc USED    VEXTA drives MSP101        #TT2
1pc used  VEXTA  CSD2112-P
1PC USED  VEXTA 2phase Oriental stepper drive CSD2109-P
1PC USED Eastern VEXTA drive CSD2112-P
1pc USED FOR VEXTA STEP MOTOR PK545-NBC-C25 ,Without wire #T86m YS
1PC Used Good VEXTA ASD13C-A #T94R YS yh
1PC Used Japan Eastern VEXTA 28 Series 1.8 degree 0.95A Double Out Axis #w2916wx
1pc USED Oriental Motor Super Vexta UDX5107N 5-Phase Stepping Motor Amplifier
1PC Used Oriental VEXTA five phase stepper drivers plate PMD03C tested
1pc USED Super Vexta 5-Phase Motor Driver Model UDX5107 Tested Good
1pc USED Super VEXTA UDX5114 5-PHASE Servo Driver Tested
1pc USED Super VEXTA UDX5114 5-PHASE Servo Driver Tested
1PC used Vexta 2-Phase Driver UDK2120 Tested
1PC USED VEXTA 2phase Oriental stepper drive CSD2109-P
1PC Used Vexta 2-Phase Stepping Motor Model PK264-02A Tested
1pc USED Vexta 5 phase Stepping Driver Motor DFC1507 Tested with Warranty
1PC USED VEXTA AXHD30K 24VDC Motor Driver Tested Good
1Pc Used Vexta AXUD40C ms
1PC Used VEXTA AXUD40C tested
1pc used VEXTA C7325-9012
1PC USED VEXTA CSD2109-P Oriental 2-phase Stepper Driver Tested Good 24-36V 1.4A
1pc used VEXTA CSD2112-P
1PC USED VEXTA CSD2120-P Oriental Stepper Motor Driver (CSD2120P) 2.8A Good
1PC Used VEXTA CSD5814N-P Oriental Stepper Driver (CSD5814NP)
1pc used VEXTA drive AXHD30K
1pc used VEXTA drive CSD5714B
1PC Used VEXTA drive MSP-1W
1PC Used VEXTA Driver ASD18B-K
1pc USED VEXTA drives MSP101 #TT2
1pc USED VEXTA drives MSP-2W
1pc USED VEXTA drives MSP-2W
1PC used Vexta Electric machinery 0GN60K
1PC used Vexta Electric machinery 0GN60K
1PC USED VEXTA MC-S0514-L
1PC USED VEXTA MC-S0514-L
1PC Used VEXTA Motor PK243-01B tested
1PC used VEXTA Motor PK566-NB  #fi
1PC used VEXTA Motor PK566-NB #fi
1PC USED VEXTA MSP101 Driver
1PC used VEXTA MSP101 Driver Tested
1PC used VEXTA MSP101 Driver Tested Free Shipping
1PC used Vexta MSP301N Speed Controller
1PC used Vexta MSP301N Speed Controller
1PC Used VEXTA Oriental drive CSD2112-P
1PC Used Vexta Oriental Motor 5 Phase Driver CSD5814N-P
1PC USED Vexta Oriental Motor CSD5814N-P  Drive card
1PC USED Vexta Oriental Motor CSD5814N-P Drive card
1PC used VEXTA Oriental Motor Drives ASD13C-A Tested
1PC used VEXTA Oriental Motor Drives ASD13C-A Tested
1PC Used Vexta Oriental Motor PK564AN-TG10 Stepping Motor Tested
1PC Used VEXTA Oriental motor speed regulator SG8030J
1PC Used VEXTA Oriental motor stepping PK566-NB
1PC USED Vexta Oriental Motor UDK5107N
1PC USED Vexta Oriental Motor UDK5107N
1PC USED VEXTA ORIENTAL SG8030J
1PC used VEXTA ORIENTAL SG8030J #fl
1PC USED VEXTA Oriental stepper drives MSP-2W
1PC Used Vexta Oriental Stepping Motor PK566-NA
1PC USED VEXTA PH265M-31
1PC Used VEXTA PH265M-31 tested
1PC Used VEXTA PK266-03A
1PC USED VEXTA PK545-NA-C21 5-phase Stepping Motor Tested
1PC USED VEXTA PK566AW Stepping Motor #T85M YS
1PC Used VEXTA Servo Driver RKD514L-C
1PC USED VEXTA SG8030J 24V #P2389 YL
1PC USED VEXTA stepper driver CMD2109P board type
1PC Used VEXTA Stepper Driver DFC5107P Tested Good Condition
1PC Used VEXTA Stepper Driver DFC5107P Tested Good Condition
1PC used VEXTA Stepper Driver PMD07U
1PC USED VEXTA Stepping driver CSD2112-P
1PC USED VEXTA Stepping driver CSD2112-P fast ship#XR
1PC USED VEXTA stepping driver PMD07U
1PC Used VEXTA Stepping motor motor PK266-03A
1Pc Used Vexta TMP-1 ic
1pc used VEXTA UDK5107N   #TT2
1pc used VEXTA UDK5107N #TT2
1PC used VEXTA UDX5114   #1
1PC used VEXTA UDX5114 #1
1pc VEXTA  5 phase stepper driver UDX5107N supporting PH569-A 10 lines  #F334 CY
1Pc Vexta 2IJ3GB-A Used nc
1PC VEXTA 2phase Oriental stepper drive CSD