著PLC的推廣普及，PLC產(chǎn)品的種類和數(shù)量越來越多，而且功能也日趨完善。近年來，從美國、日本、德國等國引進的PLC產(chǎn)品及國內(nèi)廠家組裝或自行開發(fā)的產(chǎn)品已有幾十個系列、上百種型號。PLC的品種繁多，其結(jié)構(gòu)型式、性能、容量、指令系統(tǒng)、編程方法、價格等各不相同，適用場合也各有側(cè)重。因此，合理選擇PLC，對于提高PLC在控制系統(tǒng)中的應用起著重要作用。
機型的選擇 PLC機型選擇的基本原則是，在功能滿足要求的前提下，選擇最可靠、維護使用最方便以及性能價格比的最優(yōu)化機型。 在工藝過程比較固定、環(huán)境條件較好（維修量較?。┑膱龊希ㄗh選用整體式結(jié)構(gòu)的PLC；其它情況則最好選用模塊式結(jié)構(gòu)的PLC。 對于開關(guān)量控制以及以開關(guān)量控制為主、帶少量模擬量控制的工程項目中，一般其控制速度無須考慮，因此，選用帶A/D轉(zhuǎn)換、D/A轉(zhuǎn)換、加減運算、數(shù)據(jù)傳送功能的低檔機就能滿足要求。 而在控制比較復雜，控制功能要求比較高的工程項目中（如要實現(xiàn)ＰＩＤ運算、閉環(huán)控制、通信聯(lián)網(wǎng)等），可視控制規(guī)模及復雜程度來選用中檔或高檔機。其中高檔機主要用于大規(guī)模過程控制、全PLC的分布式控制系統(tǒng)以及整個工廠的自動化等。根據(jù)不同的應用對象，表１列出了PLC的幾種功能選擇。
對于一個大型企業(yè)系統(tǒng)，應盡量做到機型統(tǒng)一。這樣，同一機型的PLC模塊可互為備用，便于備品備件的采購和管理；同時，其統(tǒng)一的功能及編程方法也有利于技術(shù)力量的培訓、技術(shù)水平的提高和功能的開發(fā)；此外，由于其外部設(shè)備通用，資源可以共享，因此，配以上位計算機后即可把控制各獨立系統(tǒng)的多臺PLC聯(lián)成一個多級分布式控制系統(tǒng)，這樣便于相互通信，集中管理。
輸入/輸出的選擇 PLC是一種工業(yè)控制系統(tǒng)，它的控制對象是工業(yè)生產(chǎn)設(shè)備或工業(yè)生產(chǎn)過程，工作環(huán)境是工業(yè)生產(chǎn)現(xiàn)場。它與工業(yè)生產(chǎn)過程的聯(lián)系是通過I/O接口模塊來實現(xiàn)的。 通過I/O接口模塊可以檢測被控生產(chǎn)過程的各種參數(shù)，并以這些現(xiàn)場數(shù)據(jù)作為控制信息對被控對象進行控制。同時通過I/O接口模塊將控制器的處理結(jié)果送給被控設(shè)備或工業(yè)生產(chǎn)過程，從而驅(qū)動各種執(zhí)行機構(gòu)來實現(xiàn)控制。PLC從現(xiàn)場收集的信息及輸出給外部設(shè)備的控制信號都需經(jīng)過一定距離，為了確保這些信息的正確無誤，PLC的I/O接口模塊都具有較好的抗干擾能力。根據(jù)實際需要，一般情況下，PLC都有許多I/O接口模塊，包括開關(guān)量輸入模塊、開關(guān)量輸出模塊、模擬量輸入模塊、模擬量輸出模塊以及其它一些特殊模塊，使用時應根據(jù)它們的特點進行選擇。 2.1 確定I/O點數(shù) 根據(jù)控制系統(tǒng)的要求確定所需要的I/O點數(shù)時，應再增加10%～20%的備用量，以便隨時增加控制功能。對于一個控制對象，由于采用的控制方法不同或編程水平不同，I/O點數(shù)也應有所不同。 表2列出了典型傳動設(shè)備及常用電氣元件所需的開關(guān)量的I/O點數(shù)。
Furnas 14FF32AAA Size 2 Motor Contactor 120V & 240V Coil 45 Amp 600V 25 HP Sz2
Furnas 42IF32AF Definite Purpose Controller 120V Coil 600 Vac 150A Contactor
Furnas 42IB32AC-D8 Magnetic Controller 240V & 480V Coil 600 Vac 150A Contactor
Furnas 42HF35AFGH Definite Purpose Controller 120V Coil 600V 120A Contactor
Furnas 42IF35AF Definite Purpose Controller 120V Coil 600 Vac 150A Contactor
Furnas 14HF32AC Size 3 Motor Starter 240V & 480V Coil 90 Amp 600V 3Ph 50 HP Sz3
fireye Type EUVS4 Flame Amplifier Module PLC Monitor fireeye Allen Bradley AB
fireye Type E500-1 Communication Interface /w Cord PLC fireeye Allen Bradley AB
Bently Nevada 7200 TACH Digital Tachometer Module PLC 72750-03-01-15-00-02
Westinghouse HMCP015E0C 15 Amp Circuit Breaker Matte HMCP015 Cutler-Hammer 15A
Mitsubishi Breaker NF-SF3020 NF SF 20 Amp 20Amp 20A 480V
Bently Nevada 7200 DVF-R Vector Filter Monitor 72730-02-15-11-00-01 7200DVFR PLC
Siemens Tiastar Furnas System 89 Size 1 Starter 30A Fused
Omron C500-ID218 Input Unit 3G2A5-ID218 C500ID218 PLC In
Square D I-Line FJA34100 100 Amp PowerPact Circuit Breaker 240/480V FJA 100A IAD
Siemens Tiastar Furnas System 89 Size 1 Starter 60A Fused 12" MCC MCCB Bucket
Square D I-Line FC24050BC 50 Amp Circuit Breaker 480V S3 Type FC FC24050 SqD 50A
Cutler-Hammer HMCP015E0C 15 Amp Circuit Breaker w/ Aux HMCP015 Westinghouse 15A
K-Unit KTS-4A-R 24V DC Signal Condition T/C Transmitter KUnit KTS4AR 24 VDC
ITE Siemens SMD69800ANGT 800 Amp Sentron Breaker 800A Type SMD6 SMD69800 damage
Siemens JXD63L400 JXD6-ETI 400 Amp A w/ 400A Trip breaker
Load Controls Incorporated PH-3A-HG 460V 4.2A 4-20ma Module Transducer CT PLC
MultiTrode Barrier Module MTISB 5 PLC Control MT1SB MTISB5 MT1SB5 FlyGT
Woodward 9905-001 M SPM-A Synchronizer 9905001 SPMA
Exide A53A3 Analog Board Microprocessor PLC 118 302 415 C Module Board 101072428
GE General Electric TFL236200WL 200 Amp Circuit Breaker 240/480/600V TFL 200A
Bently Nevada Dual Vibration XY/Gap Monitor 3300/16-05-01-01-00-00-00 PWA86739
Bently Nevada Dual Accelerometer Monitor 3300/25-01-03-03-00-00-01-00 PWA105513
Bently Nevada Dual Thrust Monitor 3300/20-03-01-01-00-00 PLC PWA135313-01 82362
Bently Nevada Dual Velocity Monitor 3300/55-01-04-02-02-00-00-05-01 PWA129958-02
Bently Nevada Dual Vibration XY/Gap Monitor 3300/16-03-01-01-00-00-00 PWA140720
Bently Nevada Dual Vibration XY/Gap Monitor 3300/16-05-01-00-00-00-00 PWA135305
Cutler Hammer Westinghouse 2100 100 Amp Reversing Size 4 Breaker MCC Bucket 100A
Exide A53A4 Diagnostic Microprocessor PLC 118 302 453 B Module Board 101072475
Westinghouse HMCP100R3C 100 Amp Circuit Breaker Matte
Exide A13A8 HT Inv Gate Timing PLC 118 302 791 A Module Board 101072973 A
Exide A100-HT Charge Lim Cntl Bd. PLC 118 302 807 A Module Board 101072981 A
Square D I-Line FC24050BC 50 Amp Circuit Breaker 480V S3 Type FC FC24050 50A IAD
Toshiba C100A-E 100 Amp Magnetic Contactor 240V Coil 600
Toshiba C-250E Size 5 Magnetic Contactor 270 Amp 120V Coil
Toshiba C-180E Size 4 Magnetic Contactor 170 Amp 120V Coil 600 Vac 150 HP Sz4
Zenith RP550 Reverse Power Relay RP-550
Westinghouse JD3250KYD04 250 Amp Switch Breaker JD3250KY JD-K 250A Cutler-Hammer
Bently Nevada Dual Thrust Monitor 3300/20-03-01-00-00-00 PLC PWA135313-01 82362
Bently Nevada Differential Expansion Monitor 3300/45-XX-XX-01-00 PLC 82803-01
Bently Nevada Eccentricity Monitor 3300/40-03-01-01-00-00 PLC PWA88796-01 82924
Bently Nevada Dual Thrust Monitor 3300/20-05-01-00-00-00 PLC PWA79482-01 82362
Allen Bradley 4100 REC AB Resolver Encoder Converter 4100REC 36 VDC PLC Module
Bently Nevada Dual Thrust Monitor 3300/20-05-03-01-00-00 PLC PWA79482-01 82362
Bently Nevada Dual Vibration XY/Gap Monitor 3300/16-02-02-01-00-00-00 PWA86739
Bently Nevada Dual Vibration XY/Gap Monitor 3300/16-01-01-02-00-00-00 PWA140720
I-T-E V7F3604 / V7F3604R 200A 600V with Hardware Vacu-Break Switch Siemens Gould
Westinghouse DK3400K 400 Amp Switch 240V Type DK-K DK3400 CH Cutler-Hammer 400A
Cutler-Hammer KES3400LS 400 Amp Digitrip RMS 310 Trip Unit w/ 350 Amp Plug 400A
Siemens ITE V7E3623 100 Amp 600V Vacu Break Panelboard Dual Switch 100A 3 Pole
Furnas 14KSU32A* Size 5 270 Amp Motor Starter w/ Dual Voltage 120V or 240V Coil
Reliance Electric 0-48652 Meter Calibration PC Board
Westinghouse JD2250F 250 Amp Matte Breaker 125 A JT2125T CH Cutler-Hammer JD2125
Honeywell 51401477-100 E Classic Backpanel 51401475-100 E PLC Chassis Rack
Honeywell 51401381-100 D 5 Slot Module Backpanel 51401379-100 D PLC Chassis Rack
Honeywell 51401381-100 B 5 Slot Module Backpanel 51401379-100 A PLC Chassis Rack
Allen Bradley 1791-24B8 Input Output Module 179124B8 24
GE General Electric SKLA36AT01200 1200 Amp Spectra Breaker 1000A SKLA36AT1200
Westronics Contactor Board CB100206-01 Rev C MC100206-01 Rev B PLC Module
Altronic EPC-200C EPC Engine Perbance Controller EPC200C Operator Interface
Allen Bradley 509-EOD-A2L Size 4 Starter 135A 120V 509EODA2L AB Sz4 592-A2LE
Trane X13650513-08 Rev K E08D41189 Horizon Chiller Control Module X1365051807
Cutler-Hammer Unitrol F10 Dual 70/100 Amp Feeder MCCB
Cutler-Hammer Unitrol F10 Dual 100 Amp A Feeder MCCB
Cutler Hammer Unitrol F10 Dual 130/70 Amp MCCB Feeder
Cutler Hammer Unitrol F10 Dual 100 Amp A Feeder MCCB
Square D FCJ34015 15 Amp Circuit Breaker 240/480V Series 3 Type FCJ-34015 15AHoneywell 620-0090 IPC 620-10/IPC 620-15 Processor Rack
Square D KCJ34225 225A Breaker 3 Pole 480V SqD KCJ-34225 Molded Case 225 Amp 3P
Allen Bradley Dynamic Brake 1336-MOD-KB050 AB 50HP 460V Series D 680-750VDC
Modicon AS-BCTR-224 A120-Compact Counter Input CTR-224
Fanuc A06B-0162-B175#0006 AC Servo Motor M6/3000 1.4 kW A06B0162B175#0006
ASEA SEK 1600K3 SEK1600K3 Contactor 1600 Amp 1600A A
Square D I-Line FA36090 90 Amp Circuit Breaker 600V S2 Type FA-36090 ILine 90A
Pepperl+Fuchs KFA5-SR2-Ex1.W.LB 1 Channel Isolator
Cutler Hammer 2100 50 Amp Size 2 MCC Bucket Electric Operator EOP1T07 MCCB
Asea CLMD63 C2 Capacitor 20 KVAR LVNQ 480V CLMD 63 ABB 20kVAR
Instrument Transber IT CT 0144D2684P011 Current Transber Ratio 1200:5 A
Cutler Hammer Westinghouse 2100 50 Amp Sz 2 MCC Bucket 18" Reversing MCCB HMCP
Westinghouse 2602D86G12 225A KAM AB De-Ion Breaker 600V 225 Amp UV Re
Square D MHP36000MMT6297 Molded Case Switch 1000A 600V MHP36000 1000 Amp Breaker
General Electric AC362RG Bus Plug Style 4 Flex-A-Plug 60 Amp 600V 3W Armor-Clad
Square D FAL360451212 45A Circuit Breaker 600VAC FAL36045-1212 45 Amp 600V FAL
Westinghouse 5685D48G74 225A KAM AB De-Ion Breaker 600V
Omron G3TA-ODX02S Relay Block Transistor Out G3TAODX02S
General Electric AC46ED6 Bus Plug Breaker Flex-A-Plug 60 Amp 600V 3W Armor-Clad
Pepperl+Fuchs KFD2-CD-Ex1.32 1Ch Volt Driver P/N 93507
Toshiba C300A-E 280 Amp Magnetic Contactor 280A 240V Coil 600 Vac 200 HP 220 Vdc
Toshiba C400A-E 320 Amp Magnetic Contactor 320A 240V Coil 600 Vac 300 HP 220 Vdc
Ward Leonard Reliance 5DP5-5021-11 Contactor 360 Amp 500 Vdc 115V Coil
Westinghouse 2609D60G24 1200 Amp AB De-Ion Breaker MOD SPL Mining Rated 600V
GE AC133ED4G 30A 480V 3PH 3W w Ground Flex-A-Plug Breaker Plug Busplug AC133ED6G
General Electric AC46ED6 Bus Plug Breaker Flex-A-Plug 60 Amp 600 V
Allen Bradley 2711-K5A16
Westinghouse 2D78522 IQ Data
Allen Bradley 1791-16B0
Warner Electric SECO SV3420-01100 SV3000 20 HP
GE General Electric SKPB36BC1200 Amp Spectra
Johnson Controls MS-NAE5510-0 MetaSys
Moore 39IDM115ACCAN PLC IDM 16107-101
Moore 39ODM115ACCAN PLC ODM 16184-61
M Moore 39SAMCAN PLC SAM 16133-71
Johnson Controls AS-UNT121-1
Schweitzer SEL-PRTU Protective Relay Terminal Input SELPRTU PRTU00-4XXXXHSX
Schweitzer SEL-121-10 Distance Relay Fault Locator SEL121 121010-4256MHNB 125V
Fisher 4194HB Wizard Pressure Control: Differential Pressure Controller 4194H-B
Bently Nevada 3500/60 Temperature Monitor PLC Module 350060 Temp Bentley
Moore 39VIMCCN PLC VIM 16171-126
Moore 39ACM24BAN PLC ACM 16139-76R
Moore 39IDM115ACCBN PLC IDM 16107-182
Honeywell Measurex GXP 054176 02 Video Printer
Honeywell Measurex 05400300 Termination
Honeywell Measurex PIDP 09437702 Module PLC
Honeywell ISSC 621-2150
Vaisala HMP233 D2C0A2AA23A1A3B
Moore 15773-11 PCB PC Board Card
Measurex Termination PIDP II/III 05379100 PLC Processor Honeywell 053791 00
Measurex Termination RS-232 05400400 PLC Processor Honeywell 054004 00 W/AB
Measurex Transition 05416300 PLC Processor Honeywell Control Processor 054163 00
Measurex 05415700 Four Channel PLC Processor Honeywell 054157 00 4 CH
Measurex 05413500 Transition Flat Panel PLC Processor Honeywell 054135 00 Type 2
Measurex QSIB Terminal 05414700 PLC Processor Honeywell 054147 00 PC Board
Measurex 05424001 Unitec Comm Term AutoBackup PLC Processor Honeywell 054240 01
Woodward Governer Co Import Control 8271-570
Siemens Tiastar Furnas 89 Size 1 Reversing Starter 30A Fused 24" MCC MCCB Bucket
Moore 15703-1 PCB PC Board Card 157031
QuickPanel GE Fanuc QPI31200E2P-B
Fisher-Rosemount CL6824X1-A2
Fisher-Rosemount CP6701X1-FA8 Power Converter Card PLC 32B7743X082 PWR 32B7745
Fisher-Rosemount CL6821X1-A6 Analog I/O w 11B7595X092 Chip P1.5.2 12P0663X032
HBM ME 50 PLC ME50 603.02-2120 260891 K Hottinger Measuring Amplifier Module
Bently Nevada Power Supply 3300/12-01-20-00 PLC PWA88219-01 78591-01A Bentley
Bently Nevada Terminal Board PWA88199-01 88286-01F PLC PWA 88199 8819901 Bentley
Modicon 170DNT11000
Modicon 170-ADM-540-80 I/O Base TSX Momentum 170ADM54080 3PT
Triconex 2553-6 24V Digital Input PLC DI External Terminator 7400056-360 25536
Triconex 2553-1 24V Digital Input PLC DI External Terminator 7400056-310 25531
Triconex 9671-810 24V Relay External Terminator PLC 7400121-380 3000290-380 PCB
Triconex 2750-2 AI / TC Termination Panel PLC 7400061-210 27502 Circuit Board
Triconex 2661-1 24V Relay External Terminator PLC 7400121-310 3000290-310 Board
ELO F50672-000 Touchscreen Display 1860
Ditech DT-V25/S Control/Interface Board DTV25 SIPA
GE Multilin SMMII-PD 511-120
Honeywell 51304487-100
GE 121AC77B811A IAC Extremely Inverse
GE Multilin PQM-A Power Quality Mete
Honeywell ISSC 627-1002
PEP VM662/642 VMEbus Single-Board
Aerosonic P_I/O_681 ISS2 PLC PEP Modular Kontron Eiko Siemens TI 004-10-05-02
GE Multilin 369-HI-0-M-0-0-0-0
Honeywell ISSC 620-0085
GE 765X21G29 JVM-5 100:1 BIL 110kV 12000V 1500VA / 1000V
Betalog Hathaway 512 309060-112
Foxboro I/A Series P0700HV-S
Foxboro I/A Series P0500RY-N
Indramat AC Servo Capacitor-TCM TCM 1.1-08-W0 219460 K39/93 PL
DIETZ electronic DSV 544CNC-3/570 AC Servo Drive Controller 174704 A 316 PLC
GE Multilin 269 269-100P-120
Cognex 560-110884.41 ICN Image Processor Board Card PLC Module SISD 460-110884.2
Cognex 560-110884.42 ICN Image Processor Board Card PLC Module SISD 460-110884.2
Cognex 560-110884.50 ICN Image Processor Board Card PLC Module SISD 460-110884.2
Foxboro I/A Series P0961BD-0C
Allen-Bradley 1794-OF41
Cognex 620-G2A P-II SBC Ver: G2 Board /w Realtime ETS Kernel Card PLC SISD 2
IEE Sixnet 03900-A3-A01-02 Display Keyboard 60-RTU-PC3-5V Power Conditioner RTU
Cognex 620-G3A P-II SBC Ver: G3 Board /w Realtime ETS Kernel Card PLC SISD 2
Miyachi Weld Checker MM-131B Module MM131B Unitek MM-1318 Technos MM1318 120V
Siemens SITOR VS AC Drive 6QG 3212-2AA00 6QG3212-2AA00 90 A
ALLEN BRADLEY 1336-BDB-SP30C
ALLEN BRADLEY 1336-BDB-SP44C
ABB Bailey NCTM01
ABB Bailey Infi 90 Net 90 IEFAN01
Bailey NMPP02
ABB Bailey Infi 90 Symphony IMFEC12
Rosemount Flow Transmitter w/display 8732CT12N0M4T1
Bailey Mass Flowmeter Main PCB 6636917A1
Bailey MCS Reset Board 6636409A1
Bailey Module UC-AS3 6635045D1
ABB Bailey NAMM03 Analog Master Net 90
ABB Bailey Infi 90 Net 90 NKLM01 4 Loop Interface Cable
ABB Bailey IMASM03 Analog Input Slav Module Infi 90
ABB Bailey Infi 90 IMDSI12 Digital Slave Input Module
ABB Bailey IMCIS12 Control I / O Input Slave Module
ABB Advant 3BHT3000025R1 DI650 Digital Input Module
ABB Advant 3BHT300007R1 DO630 Digital Output Module, 16 ch 250 VAC
Bailey Power Assembly pn: 6638763A1, or 1946949A8
ABB Bailey IPFAN11 MPSII Fan Module Infi 90, Symphony
ABB Advant 3BSE011180R PM511V0 Processor Unit
ABB Bailey IPFAN14 MPSII Fan Module Infi 90, Symphony
RIVA Runabout 2 Stroke in Water Stand with Wheel Kit
ABB Bailey NTCF03 Fiber Optic Communications Termination Unit Electric to Optic
Foxboro M/65H Indicator 65HV-OHT-PI
Moore Series 61 Booster Relay Model 610F
Moore Series 63 Constant Differential Type Flow Controller Model 63SU
Moore High Limit Relay Model 58 H
Moore High Accuracy Booster Relay Model 61 F
Foxboro 14A Flow Integrater
Foxboro Spec 200 Recorder 226s-26
Badger Research Valve 1/2'' SST 305 150 Flange # 236-Z 421
Badger Research Valve 1/2'' SST Model# 1002GCFCSSGOSFEPXX
Kepco Rack Mounted Power Module Supply HSF 24-6
Bailey IMDSI02 Infi 90 Digital Input Slave I/O Module
Kepco Rack Chassis Model RA 19 - 6 B
ABB Bailey Infi 90 Net 90 IMFBS01 Field Bus Slave Module
ABB Bailey Infi 90 IMAS001 Control Analog Output Slave Module
ABB Bailey Harmony P-HA-REPFO10000 Repeater Communications Module
ABB Bailey Infi 90 IMDS014 Control Symphony Digital Output Module Used
ABB 800XA- 3BSE013208R1 Adapter Module Bus Cluster TB820V2
ABB Bailey Infi 90 IEPMU02 Power Mounting Unit Hardware
ABB Bailey Infi 90 IEMMU02 Module Mounting Unit Hardware
Honeywell ST 3000 Smart Transmitter STD 624-E1A-00000
Bailey Level Transmitter Model PTSDLD1A1A1210C 3'' flange 150# SS
Rosemount 8701 1PA060CIN5 6'' Magnectic Flowtube
Rosemount 8705 TSA030C3G1N5W0 3'' Magnectic Flowtube
Bailey ABB NDCS03 Digital Control Station, Used
Yokogawa Controller UT 550
