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。

Allen Bradley SLC500-10 Slot Rack w/Proc 1747-L542/C &

Norgren Smart Pumps / Vacuum System - VMS 2110 24 V

Fanuc AC Servo Motor A06B-0127-B175

Allen-Bradley 1794-OB16P Flex I/O Output Module

Olsun 45 KVA 480 HV / Dry type Class AA Transformer
415Y/240-120 LV / 3 Phase

Goodyear FHP 4L280 Power Transmission Belt

Fanuc AC Servo Motor A06B-0153-B675

PILZ Pnoz 11 Safety Relay - Emergency Stop Relay

FANUC A16B-1212-0871/?12C POWER SUPPLY

Allen Bradley 1785-L40B/D Controller w/NP5 Kit

Allen-Bradley 1794-ADN Flex I/O DeviceNet Adapter

Allen Bradley AB 104-B110NZ243 Series A Contactor
Reversing Starter

ALLEN BRADLEY 500-DOD920 New In Box / 115-120 V

Honeywell Temperature Controller L456A 1008 NIB
2-Wire 250V Max - 5 Ft copper capiliary 

NIB Honeywell Serviceline Pneumatic Thermostat 
TP970A 2038 4 (Direct acting, range 60-90F)

Allen-Bradley 1794-IB10x086 Flex I/O Combo Module

Allen-Bradley 1794-IB16 Flex I/O Input Module w/TB3Base

Reliance Electric Variable Speed Drive - 125 HP 
pulled from operating Machining center

Fanuc A16B-2201-0891/?03A Ethernet Remote PCB 

Fanuc A05B-2316-C105 3 Slot Back Plane

Fanuc AC Servo Motor A06B-0356-B756

Fanuc Robotics - Brake Release Unit / 6 axis capability

FANUC A16B-3200-0040/?04C MAIN CPU PCB MODULE

FANUC A16B-1212-0931/?03B EMERGENCY STOP CONTROL
BOARD

B74 GATES HI-POWER II VBELT

GATES Part # 3740 Truflex Belt 21/32"x 74" 17x1880mm

FANUC Servo Amplifier Unit A06B-6089-H105

GATES Part # 3740 {Truflex Belt 5L 21/32" x 74"}

CONTROL TECHNIQUES 9500-8603 QUANTUM III DC DRIVE 
15-30 HP

Moog Brushless Sevro Motor / Model 306-131A - NEW

Allen Bradley PowerFlex 70 AC Drive2HP 20AD3P4A3AYNNNN?N

NIB Honeywell Heavy duty Heating/Cooling Thermostat
T6051A 1016

Square D Reversing Starter 8702 Type SDO-2 -New In Box

Square D 1S1FIS 1 KVA General Purpose Transformer Used

Allen Bradley AB 104-A75NZ243 Series A Contactor
Reversing Starter

Honeywell Ultraviolet Flame Amplifier - 7800 Series NIB
R7849 A 1023 - Solid State plug in amplifier

Allen Bradley AB 104-B180ND3 Series A Contactor
Reversing Starter

NIB Honeywell Sailswitch - 43A 1003 1 (2wire / 250Vmax)

Allen Bradley 1747-L511/B SLC 5/01 CPU 1747L511 / B

Allen Bradley 1756-DHRIO/B Logix DH+/RIO Communication

Allen Bradley 1747-L541/B SLC 500 5/04 1747L541

Allen Bradley 1747-L542/B SLC 5/04 CPU 1747L542 / B

Reliance 0-51874 Module Static Seq SCCA

Reliance 0-48652 PC Board Meter Calibration

Reliance 0-48652-25 PC Board

Reliance 0-48654 PC Board- AC Tach Rectifier

Reliance 0-49017-83 Card Pack

Reliance 0-51375 PC Board

Reliance 0-51418-4 PC Board

Reliance 0-51419 PC Board Gate Coupling

Reliance 0-51421-3 RC Network

Reliance 0-51425-1 Rectifier - AC Tach

Reliance 0-51426 PC Board- Field Loss

Reliance 0-51444 Driver Board

Reliance 0-51445 Controller Board

Reliance 0-51446 PC Board

Reliance 0-51447-3A PC Board - PC Network- 460V

Reliance 0-51486-24 PC Board

Reliance 0-51486-39 PC Board

Reliance 0-51486-56 PC Board ETR - 14 Pin

Reliance 0-51811-1 Tester Card- Voltmeter- TSTB

Reliance 0-51829-2 PC Board Linear Voltage- LVTC

Reliance 0-51831 PC Board Current Voltage CVTB

Reliance 0-51831-1 PC Board Current Voltage CVTB

Reliance 0-51831-3 PC Board Current Voltage CVTD

Reliance 0-51839-4 PC Board Relay Card IRCE

Reliance 0-51845-1 PC Board Power Supply PRSB

Reliance 0-51846-25A PC Board

Reliance 0-51847 Voltage Detector Board VLDB

Reliance 0-51848-1 PC Board

Reliance 0-51849 PC Board Gate Driver GBCA

Reliance 0-51851-5 PC Board Control Regulator

Reliance 0-51851-6 PC Board Control Regulator- CRCG

Reliance 0-51862-1 PC Board Universal Sum AMP

Reliance 0-51865 (CLDA) PC Board- Current Loop Drive

Reliance 0-51865-1 (CLDB) PC Board- Current Loop Drive

Reliance 0-51865-9 Module Current Loop DRV-CLDK

Reliance 0-51874-2 PC Board Static Sequence SSCC

Reliance 0-51881-1 Circuit Card Ext Term CNTR- ETCB

Reliance 0-51884 LSCA Moldule LOG SIG COND

Reliance 0-51890-6 PC Board DPSG

Reliance 0-51893-2 Field Controller - FCCC

Reliance 0-51893-3 PC Board- Field Exciter FCCD

Reliance 0-51899-2 Control Module Extender Card

Reliance 0-51901-A Armature Reg.

Reliance 0-51902 Driver Card

Reliance 0-51902-5 PC Board

Reliance 0-51903-A Power Supply

Reliance 0-52012 PC Board Gate Driver MaxPak

Reliance 0-52014 PC Board Timed Voltage Reference

Reliance 0-52824 Current Loop Regulator

Reliance 0-54349-2 PC Board Phase