我們新研制出一種用于紙漿白度測定的智能白度儀，該儀表采用西門子公司生產的S7-224 CPU結合軟件功能進行數據處理，具有較好的可靠性、重復性、精確度和穩定性。為了使其能與其它智能設備之間實現通信，我們將通過現場總線技術把它連接到網絡中，使它成為造紙廠現場總線控制系統的一部分。

2.現場總線的選擇

  2.1現場總線技術的選擇

  現場總線集控制技術、計算機技術、通信技術于一體，是當今自動化領域技術發展的熱點之一。這項技術可將多個智能控制儀表連接成網絡系統，實現分布式計算機控制，提高檢測和控制精度，改善系統的動態響應速度，提高系統安全性，從而得到了廣泛的應用。

  近年來，幾種有影響的現場總線技術已在一些特定的應用領域里顯示出各自的優勢。在此，我們選定了現為德國和歐洲標準的PROFIBUS（Process Fieldbus）現場總線。一方面由于它是目前數據傳輸率快的一種現場總線，傳輸率高可達12Mbps，另一方面它能夠很好的與西門子的傳動設備相配合，并與西門子PLC（Programmable Logic Controller）結合緊密且組態簡便。

  2.2 PROFIBUS現場總線簡介

  參照ISO/OSI參考模型,PROFIBUS現場總線只包含物理層、數據鏈路層和應用層。由PROFIBUS-DP，PROFIBUS-FMS， PROFIBUS-PA組成PROFIBUS系列。

  PROFIBUS-DP：經過優化的高速、廉價的通信連接，專為自動控制系統和設備級分散I/O之間通信設計，使用PROFIBUS-DP模塊可取代價格昂貴的24V或0～20mA并行信號線。用于分布式控制系統的高速數據傳輸。

  PROFIBUS-FMS ：解決車間級通用性通信任務，提供大量的通信服務，完成中等傳輸速度的循環和非循環通信任務，用于紡織工業、樓宇自動化、電氣傳動、傳感器和執行器、可編程序控制器、低壓開關設備等一般自動化控制。

  PROFIBUS-PA專為過程自動化設計，標準的本質安全的傳輸技術，實現了IEC1158-2中規定的通信規程，用于對安全性要求高的場合及由總線供電的站點。

  本設計中采用的是PROFIBUS-DP標準，PROFIBUS-DP（或DP標準）是由歐洲標準EN50170定義的一種遠程I/O通信協議。DP表示分布式外圍設備，亦即遠程I/O。PROFIBUS-DP還用到了應用層接口（ALI），ALI將過程對象轉換為通信對象。

SWICHTEC INVENSYS ENERGY MAIN POWER BOARD 350-00079-01D DRG 21135 FOR R5800 ILPS
SWICHTEC INVENSYS ENERGY DRG 21592 CIRCUIT BOARD 350-00079-18B R5800 LCD DISPLAY
SWICHTEC INVENSYS ENERGY 350-0079-54C R5848-11 RECTIFIER CONNECTOR BOARD
SPARK MODULE, SM2 INVENSYS 120V. 3mA. A10006 - AMERICAN RANGE, BAKERS PRIDE   
SONDE INVENSYS DWT 0001
SM50 Intergy Invensys Supervisory Module
SIM-CCN GCM SIEBE Barber-Colman Invensys Carrier CCN Systems Integration Module
SIEBE PP-2446 PRESSURE TRANSDUCER BARBER COLMAN TAC INVENSYS ERIE
Siebe MSC-P-751 Environmental Controls Controller (Invensys?)
Siebe MSC-P1504-D Controller Lev-11 w/ AO & clock invensys robertshaw
Siebe MSC-NCM-D Controller invensys robertshaw
Siebe MSC-NCM Network Controller W/Modem MSCNCM Invensys
SIEBE INVENSYS MPC-8AI HVAC CONTROL, MULTI-PURPOSE CONTROLLER, ANALOG INPUT - US
SIEBE INVENSYS MPC-4A0 MULTI-PURPOSE CONTROLLER, ANALOG OUTPUT MODULE -   w/G
Siebe Invensys MK-2690-0-0-2 VKS-9263-203-4-35 Actuator Valve Stainless Steel
Siebe GCM SIM-York GCM-86000 York Talk Invensys TAC Network 8000
SIEBE BARBER COLMAN INVENSYS 1/2" NPT 3-WAY CONTROL BLEND VALVE VS-9313-201-4-4
SIEBE BARBER COLMAN INVENSYS 1/2" NPT 2-WAY CONTROL BLEND VALVE VK-9211-201-4-3
Siebe Barber Coleman Invensys VK-7213-201-4-01 Valve Assembly 1/2" reduced port
Sensus Invensys ICE 5/8" by 5/8" Water Meter SRII BRAND   
SEALED   ! LAMBDA / INVENSYS POWER SUPPLY SE-500-3 SE5003
Scotsman Water Valve for CM250 120V 50/60hz 10W Invensys S-30 K-63916-12
Scotsman Water Valve 24V 60HZ 10W Invensys S-53N 283H11 K-67953
Scotsman Water Valve 24V 60HZ 10W INVENSYS K-76858
Scotsman 12-2548-01 Water Valve 24V 60HZ 10W Invensys 12-2548-01c
Schneider TAC Invensys Unit Ventilator Thermostat 2298-060    In Box
Schneider Invensys MP-495-0-2-2 Actuator 120V 50W .95A MP495022 50/60Hz
SCHNEIDER ELECTRIC, INVENSYS, TAC MN 150 LON CONTROLLER, SAT3 W/ROOFTOP PROFILE_
SCHNEIDER ELECTRIC, INVENSYS TAC MNL-V3R VAV CONTROLLER VAV MNL-V3RV2 PROFILE +_
Schneider Electric Invensys modulating valve AT13A00T Erie Pop Top
Schneider Electric Invensys diverting relay 4-20 PSIG set point 2325-502
Safetran Invensys DC to DC Converter A53106 9000-53106-0001 Rev E3
RX-19-36 ROBERTSHAW / INVENSYS FRYER THERMOSTAT FOR MILLIVOLTS RX1936 RX 19 36
ROTAVAL STAINLESS FEEDER W/ INVENSYS(.90HP) MOTOR AND RADICON GEAR  
Robertshaw Invensys Valve Model #P2
Robertshaw Invensys Range Temperature Dial Knob #4590-004
ROBERTSHAW INVENSYS MG21-1126 PRESSURE CONTROL (R2-4-24KD)
ROBERTSHAW INVENSYS GIST 100 - 320°C GRIDDLE THERMOSTAT GAS VALVE WITH IGNITION
Robertshaw Invensys Gas Thermostat,for Vulcan,Garland,Southbend #BJWA 25PC1-536
Robertshaw Invensys Gas Thermostat,3/8" FPT, #46-347
Robertshaw Invensys FD0-3-02-54 Gas Thermostat Model FD0, 461128 GARLAND   
Robertshaw Invensys Electric Thermostat,25A,250VAC,Max 325*F, #KP-87-60
Robertshaw Invensys Electric Thermostat KXT-466-36 175 to 500 Degree
Robertshaw Invensys Electric Thermostat KX-289-30 100 to 450 Degree
Robertshaw Invensys Electric Thermostat KX-289-30 100 to 450 Degree
Robertshaw Invensys Electric Thermostat 5110-052
Robertshaw Invensys Electric Oven Thermostat,30A,277VAC,Max Temp 325*F, #S-476-4
Robertshaw Invensys Electric Oven Thermostat,30A,277VAC,Max 450*F,#S-100-48
Robertshaw Invensys EA5-484-72 Electric Thermostat 180 degree max TST2528
Robertshaw Invensys Dual Solenoid Valve 3/8" FJT 120V #00497639-000G1
robertshaw invensys apl control. MC-20-1101 gard-pak III
Robertshaw Invensys Add-On Stuffing Box Kit For Capillaries #4650-001
Robertshaw Invensys 9920I Thermostat Heat Pump
Robertshaw Invensys 9801I Thermostat Gas Electric Oil Heat Pump
Robertshaw Invensys 9560 Thermostat Heat Pump
ROBERTSHAW INVENSYS 9025i REMOTE OUTDOOR SENSOR
Robertshaw Invensys 9020I Remote Sensor Indoor Use
Robertshaw Invensys 8625 Thermostat Gas Electric Oil Heat Pump
Robertshaw Invensys 8425 Thermostat Gas Electric Oil Heat Pump
Robertshaw Invensys 8401 Thermostat Gas Electric Oil Heat Pump
Robertshaw Invensys 700-705 Energy Cut Off Switch HT3 E
RobertShaw Invensys 60 to 250*F Electric Thermostat Assembly #5300-615
Robertshaw Invensys 41-1402 Hot Surface Furnace Ignitor
Robertshaw Invensys 41-1090 Hot Surface Furnace Ignitor Universal Kit
ROBERTSHAW GAS FRYER THERMOSTAT RX-1-36 MILLIVOLTS INVENSYS CATERING SPARES
Robertshaw Electric Thermostat S-224-24 5300-014 5300-01D 400 Degree Invensys
Robertshaw 5459-074 Invensys Thermostat BNP-404-64 BTP-404-60 288153
Robertshaw 5225-06G High Limit 440F/227C Thermosta Invensys LCC770240000   
Robertshaw 4020-007 Gas Safety Valve FMDA Invensys
Robertshaw 4020-005 Gas Safety Valve FMDA Invensys
Robert Shaw Thermostat Invensys 100-550°F - D1320605900
Robert Shaw / Invensys Gard-Pak 2 Solid State Motor Protector 3433-046
RELAY ELECTRIC PNEUMATIC HVAC INVENSYS 2364-211 R471-1    IN THE BOX
Reduzierung Typ EATON (INVENSYS) Durchflussrate 5,5l/min Druckbereich 1-10bar
RECEIVER CONTROLLER 2341-501 INVENSYS    IN THE BOX
Ranco Invensys L30-83 Solenoid Coil 24 VDC for V1-V12 Reversing Valve Heat Pump
Ranco / Invensys A30-181, ADAPTABLE REFRIGERATOR CONTROL
R2948 Intergy Invensys Rectifier Module
PROV-GCM Proview Programmer/Operator Keypad MMI Invensys Barber-Colman Siebe TAC
Pneumodular Diverting Relay Robertshaw Or Invensys 2353-501    In The Box
Pneumodular Diverting Relay Robertshaw Or Invensys 2353-501    In The Box
Pitco P5047588,Vulcan 410837-1, Invensys GSA60301800, Gas Thermostat 66-1017   
PEM-1 Invensys Barber Colman Siebe Packaged Equipment Module
PEM 1 BARBER COLMAN SIEBE INVENSYS TAC NETWORK 8000 PEM-1 PEM1 _
PEM 1 - BARBER COLMAN NETWORK 8000, SIEBE, INVENSYS, TAC
Peco/T.A.C./Invensys/Schneider Elec - TA-168-9 Manufacturer discontinued GREAT!!
P0917LYFPS40024 - FOXBORO - P0917LY FPS400-24 INVENSYS POWER SUPPLY  
ORIGINAL AC POWER ADAPTER FOR INVENSYS WONDERWARE KONTRON TUOCH PLANEL
NOS! INVENSYS DC TO FREQUENCY CONVERTER 7500-5016-1 750050161
NOS Invensys Valve Body 2-Way VB-7213-0-4-08 VB-7213-000-4-8 1" 14 CV
NOS Invensys Schneider Electric Valve Linkage for Gear Train Actuators AV-390
NOS INVENSYS CONTROLS 10-250 SHANK EXTENSION 2"
NOS INVENSYS 2374-498 AIR SENSING SWITCH RSS-498
NIB Invensys Local Control Module Base Assembly LCMA 104-1-0-1 Barber Colman
  ! Ranco Invensys 13109 Motor Actuator 127-00022-001 (128) 12V 1/2"
  ! Invensys APV Actuator SW43T10A1E5 Divert Valve
   Whitton Brook Invensys Crompton Fuel Pump & Motor A-EF180MZ-D 8004-1064
   Thermostat by INVENSYS S-112-18 5300-09H 125 VA 120-270 VAC MT 400 F
   TAC INVENSYS PNEUMATIC ACTUATOR VALVE LINKAGE KIT MK-2690 AV-400-0-0-1
   TAC Invensys MMC-420 Actuator Control Modules
   STATE-A.O. SMITH 9000547005 GAS CONTROL VALVE*INVENSYS/ROBERTSHAW
   SIEBE AT-523-11-1 RELAY REPAIR KIT INVENSYS BARBER-COLMAN
   Schneider Invensys Barber Colman Diaphragm Actuator MK Series 6" x 4.5"
   ROBERTSHAW INVENSYS MINI-GARD PRESSURE CONTROL MG20-1098 MPL-7003 3100-051
   Robertshaw Invensys INT-43 10-546 Add-A-Wire Thermostat Wiring Adapter
   ROBERSHAW-INVENSYS VS 4010-001 SAFETY VALVE-COMMERCIAL*FMC*NLA/Obsolete
   Overstock Invensys Controls Heavy Duty Refrigerant Hose 48" 1290132-B48
   Overstock Invensys Controls Heavy Duty Refrigerant Hose 36" 1290132-B18
   Overstock Invensys Controls Heavy Duty Refrigerant Hose 24" 1290132-B24
   Overstock Invensys Controls Heavy Duty Refrigerant Hose 18" 1290132-B18
   Open Box INVENSYS 3PSI-15PSI GAUGE 250-3074
   OLD INVENSYS PRESSURE TRANSMITTER 0-6IN H2O 863DPM2D1NKMP FOXBORO GG
   listing    Invensys RKS-2001-0-1 Receiver Controller.   
   listing    Invensys Foxboro D0135ND Electric Level Sensor ORIGIN 2A8716 C0-NI G/M
   listing    Foxboro P0916FL Rev C 32ft Length Cable I/A Series PLC Invensys PO916FL 32'
   listing    Foxboro P0916DY Rev B 32ft Length Cable I/A Series PLC Invensys PO916DY 32'
   listing    Foxboro P0916DE Rev C 32ft Length Cable I/A Series PLC Invensys PO916DE 32'
   listing INVENSYS TC-4252 ELECTRIC BULB THERMOSTAT 2 STAGE M & M CONTROL
   listing Invensys Barber Colman CP-8552 Transducer
   listing Invensys Auxiliary Switch Kit - 2 Spot Switches -   !
   listing Foxboro P0916FL Rev C 18.5ft Length Cable I/A Series PLC Invensys PO916FL 18.5'
   listing Foxboro P0916FK Rev C 18.5ft Length Cable I/A Series PLC Invensys PO916FK 18.5'
   listing Foxboro P0916FK Rev B 18.5ft Length Cable I/A Series PLC Invensys PO916FK 18.5'
   listing Foxboro P0916FJ Rev C 10ft Length Cable I/A Series PLC Invensys PO916FJ 10'
   listing Foxboro P0916DX Rev B 18.5ft Length Cable I/A Series PLC Invensys PO916DX 18.5'
   listing Foxboro P0916DE Rev C 32ft Length Cable I/A Series PLC Invensys PO916DE 32'
   listing Foxboro P0916DD Rev C 18.5ft Length Cable I/A Series PLC Invensys PO916DD 18.5'
   listing Foxboro P0916DD Rev B 10ft Length Cable I/A Series PLC Invensys PO916DD 10'
   listing FOXBORO ECKARDT INVENSYS 139PP-ASEC5 PNEUMATIC PRESSURE REPEATER   
   listing Eurotherm Invensys Barber-Colman Ea22 120v Actuator
   listing BARBER COLMAN SIEBE INVENSYS TAC NETWORK GCM - 86120
   INVENSYS-ROBERTSHAW VC 4220-013 COMMERCIAL OVEN THERMOSTAT*NLA/OBSOLETE
   INVENSYS-ROBERTSHAW 700-101 MANUAL GAS VALVE