PLC與電氣回路的接口，是通過輸入輸出部分（I/O）完成的。I/O模塊集成了PLC的I/O電路，其輸入暫存器反映輸入信號狀態(tài)，輸出點反映輸出鎖存器狀態(tài)。輸入模塊將電信號變換成數字信號進入PLC系統(tǒng)，輸出模塊相反。I/O分為開關量輸入（DI），開關量輸出（DO），模擬量輸入（AI），模擬量輸出（AO）等模塊。
常用的I/O分類如下：
開關量：按電壓水平分，有220VAC、110VAC、24VDC，按隔離方式分，有繼電器隔離和晶體管隔離。
模擬量：按信號類型分，有電流型（4-20mA,0-20mA）、電壓型（0-10V,0-5V,-10-10V）等，按精度分，有12bit,14bit,16bit等。
除了上述通用IO外，還有特殊IO模塊，如熱電阻、熱電偶、脈沖等模塊。
按I/O點數確定模塊規(guī)格及數量，I/O模塊可多可少，但其最大數受CPU所能管理的基本配置的能力，即受最大的底板或機架槽數限制。
可編程控制器，英文稱ProgrammableLogicController，簡稱PLC。PLC是基于電子計算機，且適用于工業(yè)現場工作的電控制器。它源于繼電控制裝置，但它不像繼電裝置那樣，通過電路的物理過程實現控制，而主要靠運行存儲于PLC內存中的程序，進行入出信息變換實現控制。
PLC基于電子計算機，但并不等同于普通計算機。普遍計算機進行入出信息變換，多只考慮信息本身，信息的入出，只要人機界面好就可以了。而PLC則還要考慮信息入出的可靠性、實時性，以及信息的使用等問題。特別要考慮怎么適應于工業(yè)環(huán)境，如便于安裝，抗干擾等問題。
Heidenhain EXE 610 B Scale Interpolation Box EXE610B L1
Heidenhain EXE 610 H3 Scale Interpolation _ EXE610H3
Heidenhain EXE 610 E10 Scale Interpolation _ EXE610E10
Heidenhain EXE 610 D12 Scale Interpolation _ EXE610D12
Heidenhain EXE 610 D11 Scale Interpolation EXE610D11
Heidenhain EXE 610 E6 Scale Interpolation box EXE610E6
Heidenhain EXE 650B x25/10 NEW
HEIDENHAIN LINEAR ENCODER LS 473 ML170 ID# 403 210 1C
Heidenhain LIF 17R Id.Nr. 343 820-02
Used Heidenhain Encoder ROD 426 1000 27S12-03 ID:295 434-L5
Used Heidenhain Encoder ROD 426E.011- 1000 249 884 04
HEIDENHAIN CORP 406-445-11 USPP 40644511
Heidenhain PLD 16-8 PLC I/O extension module. I.D 360916-11
HEIDENHAIN CORP 295-281-CK NSPP 295281CK
Heidenhain Interpulation Box 2627780 #16666
XVGA box , replace Heidenhain monitor to LCD for BC110B BC120 BE211 BE411 NEW!
Heidenhain industrial monitor replacement ,to VGA XVGA LCD CRT Video Converter
Heidenhain Miniature Rotary Encoder Rod 1020 322-808-29
Heidenhain Linear Scale 403 210 1M (LS473) "NEW IN BOX"
Heidenhain Amplifier/Inte?rpolation Box EXE 602 D/5-F x2
Heidenhain Interpolation Box EXE 650 B X25/10_EXE 650 B X25-10_EXE650B?X2510
Heidenhain 49" Scale LS 403_LS403_LS 4O3_LS4O3_LS 403 2186_LS4032186?_LS4O32186
HEIDENHAIN CORP 295-434-LP NSPP 295434LP
Heidenhain EXE 650 B X25/8 Amplifier Interpolation Box
Heidenhain EXE 650 X25/10 Amplifier Interpolation Box
Heidenhain Rotary Encoder 251-681-02 Rod 426B-2500
HEIDENHAIN INTERPOLATION UNIT IBV 610 277 236-22
HEIDENHAIN CORP 78871428 FNFP 78871428
Heidenhain Co. Interpolation & Digitizing M# 27723621
HEIDENHAIN CORP 602E-EXE-NR-24?6-842-02 NSPP 602EEXENR24684?20
Heidenhain EXE 650 BX25/8 Interpolation Box 263-380-30
HEIDENHAIN Encoder # ROD 420.0000-600 257 949 56 NIB!
Heidenhain VRZ 403 Display
HEIDENHAIN LINEAR OR ANGLE ENCODER INTERPOLATION UNIT EXE 610C / 263 383 01
HEIDENHAIN CORP 385480-03 NSFP 38548003
HEIDENHAIN CORP ROD-426.001B-1?125 USPP ROD426001B1125
Heidenhain Corp 406 038 17 40603817 Encoder USED
Heidenhain Corp 406 020 2V 4060202V Encoder USED
HEIDENHAIN CORP 295434-32 NSFP 29543432
HEIDENHAIN CORP 295434-94 NSFP 29543494
HEIDENHAIN CORP ROD-426-B-400 USPP ROD426B400
HEIDENHAIN CORP ROD-426.011B-2?000 USPP ROD426011B2000
HEIDENHAIN ROD 426 3000-03S12-03 USED ENCODER
HEIDENHAIN EXE 602 D/5-F (986)
HEIDENHAIN ENCODER ROD 426 2000 15S15-08
Heidenhain Linear Encoder LIP 47R
Heidenhain LIF 48R Linear Encoder
HEIDENHAIN LS106 LINEAR ENCODER USED
HEIDENHAIN ERN 1020-1000/ 403420-42 ENCODER NEW IN BOX
Heidenhain IBV 610 Encoder Interpolation Digitizer
HEIDENHAIN ERN-420-3600-0?1 ENCODER ERN420
NEW HEIDENHAIN ROD-529/2A13.0?8192-RU-KN ENCODER ROD5292A130819?2RUKN
HEIDENHAIN ERN 471 5000 16S15-OV Encoder
Heidenhain Encoder 1420 217-262-44 used
Heidenhain Interpolation Digitizing Box EXE 610C 263383
Heidenhain Interpolation Digitizing Box EXE 602E 246842
Heidenhain Interpolation Digitizing Box EXE 650B 263380
Heidenhain Cable 310 126 03 31012603 12 pin new
Heidenhain GPIB Display Encoder ROD Angle Rotary Linear Optical Quadrature
Heidenhain Rotary Encoder 295434-30 Rod 426
Heidenhain 650B X25/8 Interpolation Box
Heidenhain Encoder ERN 120.M003-5000 281576-08 NIB
Heidenhain Encoder Roc 410.3GP7-10B00 290028-16
HEIDENHAIN 40340011 SIGNAL SPLITTER (2517)
Heidenhain 40340011 Signal Splitter Unit ! WOW !
HEIDENHAIN OUTPUT BOARD CAT#VK030
Heidenhain 337 641-51 Rotary Encoder Compact Integral Bearing 5VDC 337641-51
Heidenhain 295-791-08 Linear Encoder D-83301 ! WOW !
HEIDENHAIN INPUT BOARD CAT#VHD 40
HEIDENHAIN EP90 CELL PILOT CAT#31867601
Heidenhain 403 423-11 Rotary Encoder Compact Integral Bearing 5VDC 403423-11
Heidenhain 369124-06 Adapter Cable new
Heidenhain EXE 610B Scale Interpolation Box
Heidenhain Rotary Encoder ROD 446 1800 258-438-31
HEIDENHAIN LINEAR ENCODER LS 473 ML120 ID# 403 210 2E
Heidenhain Cable 263299-01 9 pin new
Heidenhain 332115-15 Adapter Cable 02B017 ! NEW !
Heidenhain Rotary Encoder ERN 180, Cable, IBV 101 DF18
HEIDENHAIN AK LIP 50 Id.Nr. 311 134-12 NEW SURPLUS
HEIDENHAIN EXE 602 D/5 - F Digital Readout Amplifier - Lot of 2
Heidenhain Interruption Box 262 788 01 #17793
bridgeport heidenhain tnc 151 i/o board card 227278
within 3 days
HEIDENHAIN PULSE SHAPER FOR LINEAR SCALE EXE 602E
EXE610C Heidenhain Control, SN 5802019
HEIDENHAIN VRZ 403 G2 ELECTRONIC COUNTER
Heidenhain LIDA 48 Linear Encoder Readhead LIDA48 363956-02 NEW
HEIDENHAIN LIDA 48 369428-01 SCANNING HEAD
Heidenhain EXe650 B X25/8 263 380 30 Interpolation Box
Heidenhain Interpolation Box EXE 610C Id.Nr.263 383 01
IFM/EFECTOR/HE?IDENHAIN RV6129 RV-0100-I24/S S 295 280-4B ENCODER 10-30VDC *NIB*
Dr. Johannes Heidenhain Y Axis Optical Encoder
Dr. Johannes Heidenhain X-Axis Optical Encoder
Heidenhain 650B X50/8 Interpolator
within 3 days
HEIDENHAIN ROD 1424 1250 H7 ROTARY ENCODER ID NR 228 943 03
HEIDENHAIN ROD 1424.0001 1000 H10 ROTARY ENCODER ID NR 245 026 02
HEIDENHAIN ROD 456.003 1024 K1 ROTARY ENCODER ID NR 240 135 01
HEIDENHAIN ROD 426 B ROTARY ENCODER ID NR 25168102
HEIDENHAIN ROD 1424-1250 G9 ENCODER
Heidenhain LIF 48R
HEIDENHAIN EXE 610C INTERPOLATION DIGITIZER BOX EXE610C
Heidenhain Interpolation Digitizing Digitalizer Interpolator Box IBV 660B &cable
HEIDENHAIN CORP ROD-426-1024 USPP ROD4261024
HEIDENHAIN CORP 376846-LP NSFP 376846LP
Heidenhain Operating Manual TNC Contouring Control 151 B 151 Q_155 B 155 Q_1988
Heidenhain Encoder 295 434 87 "NEW IN BOX"
Heidenhain Amplifier Interpolation Box Exe 605 #7524SO
Heidenhain Encoder ROD 426 2000 03S12-03_ROD42?6200003S1203_R?OD 426 2OOO O3S12-O3
Heidenhain EXE 602 D/5-F G12 G 12 DRO Box #235 322 28
Heidenhain Incremental Encoder ROD 426 1500 (1500 Line Counts / Rev) EXCELLENT!
Heidenhain ROD 426 1024 Encoder NEW SURPLUS, ROD426 1024 30B10-1A
ROD250 HEIDENHAIN
HEIDENHAIN CORP 310740-03 NSFP 31074003
JOHANNES HEIDENHAIN DIGITIZING ELECTRONIC SCALE AND SZ3 WIRE
JOHANNES HEIDENHAIN DIGITIZING ELECTRONIC SCALE AND SX3 WIRE
JOHANNES HEIDENHAIN DIGITIZING ELECTRONIC SCALE AND SY3 WIRE
JOHANNES HEIDENHAIN CABLE WIRING FOR DIGITIZING SCALE
Heidenhain D-83301 Encoder
Heidenhain SME 50 X50/2, EXE 50 X50 2 Interpulation Box
HEIDENHAIN 413 512 27S17-58 14V COMPACT ROTARY ENCODER
NEW HEIDENHAIN 532571-09 CABLE
Heidenhain transducer LS 473 X 320MM
HEIDENHAIN ROD 466 1024 30B10-2B ENCODER
Heidenhain EXE-602-D Signal Conditioner ! WOW !
HEIDENHAIN CORP 403555-15 NSFP 40355515
在線咨詢 
