若主机单元的I/O数量不够用，可通过I/O扩展接口电缆与I/O扩展单元(不带CPU)相接进行扩充。 PLC还常配置连接各种外围设备的接口，可通过电缆实现串行通信、EPROM写入等功能。
编程器作用是将用户编写的程序至PLC的用户程序存储器，并利用编程器检查、修改和调试用户程序，监视用户程序的执行过程，显示PLC状态、内部器件及系统的参数等。
编程器有简易编程器和图形编程器两种。简易编程器体积小，携带方便，但只能用语句形式进行联机编程，适合小型PLC的编程及现场调试。图形编程器既可用语句形式编程，又可用梯形图编程，同时还能进行脱机编程。
AMI UCLP207-23 Pillow Block Bearing UC207-23 LP207 ASAHI with Grease Fitting
Box of 10 OEM ABB 1SVR405621R1100 CR-U024DC2L Pluggable Interface Relays
Omron C200H-OD219 PLC Output Unit C200HOD219 Free Shipping!
Mitsubishi / Mazak PC Board. CIN634A195G51A, MC435-1,
MS2M10679 OEM Controls JOYSTICK SINGLE AXIS SPRING RETURN TO CENTER
Fafnir Survivor G1100KRRBC1 Bearing
Mitsubishi NF-SF 3P 50A CE 1J6B2207 25H708 Circuit Breaker KBQ-B8176
Fanuc Amplifier, A02B-0118-B002, W/A16BD, A16BB (7)
ESW Electronic Systems Of Wisconsin Rev A PCB Board
Rexroth Indramat Motion Control Module, FWA-MTCR0*-MO1-18VRS-NN,
Yaskawa Hicup DC Servo Motor w/ Brake, UGHMED-20-TMA2,
Nu OEM Konica Magenta Imaging Unit pc/ua
GE Fanuc A16B 1 Memory Board
Bailey ABB G1 Circuit Mother Board Assembly PCB Free Shipping!
New(?) Used(?) MKS Angle Valve
Total Source BQ20E/03 DX23926 Cone Roller Bearing
Allen Bradley 2755-LD4S1X4 Scanner Assembly
Okuma 4.3 kW AC Servo Motor, # BL-MC140E-30T, 3000 RPM,
Deublin Union TC/C, ,
Yaskawa Motherboard, JANCD-MM09-03, DF Rev. B1,
Omron C200HW-BI051 PLC Base Unit with 30 Day Warranty
YASNAC YASAKAWA JANCD-FC200 Circuit Board, DFDO REV D05,
Euchner ZSA092141C2038 92141
Gould Modicon P001 PLC Power Supply Unit VAC Supply
Fafnir Super Precision Roller Bearing, 2MM9318WI CR DUL,
Fanuc # 20S/1500 AC Servo Motor, # A06B-0505-B203,
Fabco-Air TC-221-X-A3-LF Pneumatic Pancake Cylinder TC221XA3LF Free Ship!
Sanyo Denki / NEC AC Servo Motor, DFSMD,
Fanuc PC Board, # A16B / 04A ,
Sick Light Curtain Receiver, FGSE 600 mm, OLD STOCK,
NTN UCFC208D1 Bearing
Siemens 6EP4134-0GB00-0AY0 Battery Module
Yaskawa AC Servo Motor, SGMG-44ASAAB, 1500 PM,
KR30-PP Bearing
Bosch Valve 0 821 300 972 0 821 300 974
GE Fanuc Model OS AC Servo Motor, # A06B-0313-B703 #0075, AT113,
Infinity Andover Controls EMX160
Siemens Sinumerik 810M Servo Interface, 40 mm, 6FX1121-4BB03,
Factory Sealed IEE AWX1 Keyboard Display Monitor
