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。
LiteLink (Liteway) CT 1 CH TX, 1310nm, Contact Closure
Boonton DC to 2.0 GHz, 20 dB, Type N (M-F), Fixed Coaxial Attenuator
Square D Control Module AS42CM-T #55845
Marconi J, 25 to 1000 MHz, Directional Power Head + Cable
Cosel CDS 36-76 VDC, 28.0 V Output, 18.000 Amps, 504.00 W DC-DC Converter
Festo Electric Control Block / Valve Terminal IFB8-02 #52740
Sick Safety Interlock iE 1000 ES1 #67203
Smc Cylinder Actuator MLGCLBE #75507
(X9-16) 1 GOULD MODICON AS-500P-000 REV H6 P190 PROCESSOR BOARD
Festo Electric Control Block / Valve Terminal IFB8-02 #52812
Vickers Directional Control Valve DG4V36CMP7H750JA100 #74157
Love Controls Temperature Controller 16A
1 Nib Smc AcG Filter Regulator Lubricator Combo (Q10-6)
(9031) Asco Valve Repair Kit 302359 for 8215 Series
(R1-1) ALLEN BRADLEY 150-A16JB SOFT START IN ENCLOSURE
Dpd2T-A150Ss Pressure Switch
HP / Agilent 10503A, 48" Length, 50 ohm, BNC (M-M) Cable Assy.
(H11) 1 HONEYWELL BZV6-2RQ62 LIMIT SWITCH
Festo Electric Control Block w/ Valves IFB8-03 #70460
(0646) Vickers Amplifier EEA-PAM-535-B-30 for KFDG4V-5
ALLEN-BRADLEY 1784-PCM5/B CABLE WITH 1784-PCMK MEMORY CARD
Dremel 7200 BPM, 115 VAC, 2 A, Engraving Pen w/ Carbide Tip, Tested!
Barber Colman Control Card Rack 45AA-OCC Scratch & Dent #23910
LOT OF 10 ALLEN-BRADLEY 700-C1 CONTACT CARTRIDGES
HP / Agilent 81521B, 900 to 1700 nm, +3 to -80 dBm, Optical Power Sensor Head
(6488) BEI Encoder H25E-F1-SS-1250-ABZC-8830-LED-EM18-S 5VDC
General Microwave D1956 (OPT 3, 10) 6 to 12 GHz, SMA (M-F) Absorptive Modulator
(7545) Marposs Gauge Head XXX
Festo Electric Control Block IFB1-02 #52737
(U1) 1 UNIMATION INC D918S3 REV F PC BOARD
(G-TOP14) ABB DSDXB001 I/O MODULE
Sumitomo Controller UF1812-1A500 #10106
(10261) Sandvik TM2000 Front Panel Process Controller
Semitronics EN625M Smartlog PGV Series, Personal Grounding Verifier
ABB 706782T03 UPPER BASE MOLDING AND CONTACTS
(0543) Magnetek 46S Drive Board
(4160) Siemens Power Supply C73451-A3000-C10 DR20 24 VAC
(J3) 1 ALLEN BRADLEY 1336-B010-EOD-L3 DRIVE
ALLEN BRADLEY 74A86 COIL
