PLC是以微处理器为基础，综合了计算机技术、自动控制技术和通信技术，用面向控制过程面向用户的“自然语言”编程，适应工业环境，简单易懂、操作方便、可靠性高的新一代通用工业控制装置。PLC是在继电器顺序控制基础上发展起来的以微处理器为核心的通用自动控制装置。

可编程序控制器是一种数字运算操作电子系统，专为在工业环境下应用而设计。它采用了可编程序的存储器，用来在其内部存储执行逻辑运算、顺序控制、定时、计数和算术运算等操作指令，并通过数字的、模拟的输入和输出，控制各种类型的机械或生产过程。可编程序控制器及其有关的外围设备，都应按易于与工业控制系统形成一个整体、易于扩充其功能的原则设计。

PLC产品种类繁多，其规格和性能也各不相同。对于PLC，通常根据其结构形式的不同、功能的差异和I/O点数的多少等进行大致分类。

按结构形式分类

根据PLC的结构形式，可将PLC分为整体式和模块式两类。

整体式PLC

整体式PLC是将电源、CPU、I/O接口等部件都集中装在一个机箱内，如图所示。具有结构紧凑、体积小、价格低的特点。小型PLC一般采用这种整体式结构。整体式PLC由不同I/O点数的基本单元（又称主机）和扩展单元组成，基本单元内有CPU、I/O接口、与I/O扩展单元相连的扩展口以及与编程器或EPROM写入器相连的接口等；扩展单元内只有I/O和电源等，而没有CPU。基本单元和扩展单元之间一般用扁平电缆连接。整体式PLC一般还可配备特殊功能单元，如模拟量单元、位置控制单元等，使其功能得以扩展。

2）模块式PLC

模块式PLC将PLC的各组成部分分别做成若干个单独的模块，如CPU模块、I/O模块、电源模块（有的含在CPU模块中）以及各种功能模块。模块式PLC由框架或基板和各种模块组成，模块装在框架或基板的插座上，如图所示。这种模块式PLC的特点是配置灵活，可根据需要选配不同规模的系统，而且装配方便，便于扩展和维修。大、中型PLC一般采用模块式结构。

还有一些PLC将整体式和模块式的特点结合起来，构成所谓的叠装式PLC。叠装式PLC的CPU、电源、I/O接口等也是各自独立的模块，但它们之间是靠电缆进行连接的，并且各模块可以一层层地叠装。这样，不但系统可以灵活配置，还可做得体积小巧。

2.2.按功能分类

根据PLC的功能不同，可将PLC分为低档、中档、。

（1）低档PLC

低档PLC具有逻辑运算、定时、计数、移位以及自诊断、监控等基本功能，还可有少量模拟量输入/输出、算术运算、数据传送和比较及通信等功能，主要用于逻辑控制、顺序控制或少量模拟量控制的单机控制系统。

 FedEx /DHL  ONE NEW VEXTA 31K15GN-A
 FedEx /DHL  ONE NEW VEXTA AID75A-C
 FedEx /DHL  ONE NEW VEXTA CMD2112P
 FedEx /DHL  ONE NEW Vexta FBLM575W-GFB
 FedEx /DHL  ONE VEXTA RKD507-A
 FedEx /DHL  ONE Vexta RKD514L-A
 FedEx /DHL  ONE VEXTA VEXTA Motor / PK534-NB
 Honeywell DDC controller XL20 CH/XL20CH WITH FAST SHIPPING
 KOHZU MOTORED PRECISION TILTING STAGE SH07-01,VEXTA PK543-NA WORKING FREE SHIP
 NEW Oriental Motor CSD5814N-P 5-Phase Stepper Driver Drive Japan
 UDX5128N VEXTA stepper driver 60 days warranty
 Vexta 2 Phase Stepping Motor PH299-02B
 VEXTA 5-PHASE DRIVER UDK5107N PK543AW1-H50 STEPPING MOTOR HARMONIC REDUCER 50:1
 VEXTA 5-PHASE DRIVER UDK5114NW2
 VEXTA ASC46AK-T30 MOTOR & DRIVER / ASM46AK-T30 / ASD18B-K
 Vexta C7810-9012K - Transf. Arm Z-Axis Motor 718.84461 - Siemens BN Prospec
 Vexta DGM85R-ASAA Hollow Rotary Actuator P/N ASM46AA-D w/ASD13B-A DRIVE
 VEXTA Servo Stepper motor ASM66AA-T7.2
 VEXTA STEPPING MOTOR 5-PHASE PX533MH-B, CSD5807N-P DRIVE TESTED WORKING FREE
(2) ALLIANCE INJECTOR ASSEMBLIES PLC / LC - VEXTA PH265-04-C18 STEPPING MOTOR
(LOT OF 4) ORIENTAL MOTOR CO VEXTA STEPPING MOTOR PK564AU-TG30 5-PHASE
(NIB)  VEXTA ASD12A-C/200-230V Closed Loop Stepper Motor Drive
(NIB)  VEXTA BLESS DC MOTOR DRIVER BXD200A-C
(NIB)  Vexta Servo Motor Pk569naw
(NIB) Oriental Motor Vexta  stepping  Motor ASM66AC  & diver  ASD12A-S
(NIB) Oriental Motor Vexta stepping Motor ASM66AC & diver ASD12A-S
(NIB) Oriental Vexta ASD24A-A Servo Motor Driver
(NIB) VEXTA ASD12A-C/200-230V Closed Loop Stepper Motor Drive
(NIB) VEXTA BLESS DC MOTOR DRIVER BXD200A-C
(NIB) Vexta Servo Motor Pk569naw
(USED) VEXTA SPG8800
**USED VEXTA PH266-01GK-C55 90days warranty Free DHL or EMS
**USED VEXTA PH266-01GK-C55 90days warranty via DHL or EMS
**USED VEXTA PK545NAW  90days warranty via DHL or EMS
**USED VEXTA PK545NAW 90days warranty
**USED VEXTA PK545NAW 90days warranty via DHL or EMS
**USED VEXTA PKE566BC 90days warranty
**USED VEXTA PKE566BC 90days warranty Free DHL or EMS
**USED VEXTA PKE566BC 90days warranty via DHL or EMS
**USED VEXTA Stepper motor ASM46AK
**USED VEXTA Stepper motor ASM46AK via DHL or EMS
**USED VEXTA Stepper motor ASM46AK via DHL or EMS 1
**USED VEXTA Stepper motor DGM60-ASAK Free DHL or EMS 1
**USED VEXTA Stepper motor DGM60-ASAK via DHL or EMS 1
*1 YEAR Warranty* - Customized Service - Fast Shipping
*NEW* VEXTA FBL5120AW-15  ORIENTAL MOTOR E55106A1 GEAR HEAD DRIVER SPEED CONTROL
*NEW* VEXTA FBL5120AW-15 ORIENTAL MOTOR E55106A1 GEAR HEAD DRIVER SPEED CONTROL
*NIB* VEXTA BLD30A-F BLESS DC MOTOR DRIVER
*NIB* VEXTA BLD30A-F BLESS DC MOTOR DRIVER
*Recertified* Matrox Odyssey XCL O10G5MDBCL* Y7108-04 010G5MDBCL* Warranty
*USED  VEXTA PK545NBW-C30  Free DHL or EMS
*USED  VEXTA PK545NBW-C30  via DHL or EMS
*USED  VEXTA PK546PA  Free DHL or EMS
*USED  VEXTA PK546PA  via DHL or EMS
*USED VEXTA PK545NBW-C30 Free DHL or EMS
*USED VEXTA PK545NBW-C30 via DHL or EMS
*USED VEXTA PK546PA Free DHL or EMS
*USED VEXTA PK546PA via DHL or EMS
[2UNIT] ORIENTAL VEXTA STEPPING MOTOR ARM24SAK-T10
[Lot Of 5] Oriental Motor Vexta Synchronous Motor Smk5100A-Aa Smk5100Aaa
[New Other] ORIENTAL VEXTA / BLFD60C2 /  DC MOTOR DRIVE, Case breakage
[New Other] ORIENTAL VEXTA / BLFD60C2 / DC MOTOR DRIVE, Case breakage
[New Other] VEXTA / KBLM6180GD-CM / AC SERVO MOTOR, 180W
[New Other] VEXTA / KXPM5120-AB / AC SERVO MOTOR, 120W
[Used] ORIENTAL VEXTA / ASD12A-SSS / DRIVER, 1.5A
[Used] ORIENTAL VEXTA / PK564AN-TG7.2 / 5-Phase Steeping Motor
[Used] ORIENTAL VEXTA / PK569K-NACM / Stepping Motor
[Used] ORIENTAL VEXTA / UPH5913H-A / Stepping Motor
[Used] VEXTA / A4809-9215KE / 5-Phase Stepping Motor, DC 1.4A, 1.1?
[Used] VEXTA / A4934-9415KPGE / 5-Phase Stepping Motor, DC 1.4A, 2.3?, Dent
[Used] VEXTA / AF-MI-LG-1x-V2, PH265-01 / Actuator, Stepping Motor
[Used] VEXTA / ASM66AA-P10 / Stepping Motor
[Used] VEXTA / ASM66AC-P7.2 / Stepping Motor, DC 5.4V, 0.8A, 1pcs
[Used] VEXTA / EM569-NA / 5-Phase Stepping Motor, DC 1.4A, 2.1?, 1pcs
[Used] VEXTA / KBLM460GD-AM / AC SERVO MOTOR, 60W
[Used] VEXTA / KBLM6180GD-AM / AC SERVO MOTOR, 180W
[Used] VEXTA / KBLM6180GD-C 6GD30K / GEAR MOTOR
[Used] VEXTA / KXPD180-CBZ / AC SERVO DRIVER
[Used] VEXTA / PK596K-NACM / 5-Phase Stepping Motor, DC 1.4A, 1.5?
[Used] VEXTA / RKD507-A, PK543ABW-H50S / 5PH Motor, Drive Set
[Used] VEXTA / UDK5150 / 5-PHASE DRIVER
[Used] VEXTA / UPH566H-B2 / 5-Phase Stepping Motor, 1.4A, 2.26?
[Vexta] RK543AA-T7.2 Stepping Motor Set 5Phase 110V RKD507-A PK543AW-T7.2 NIB
? [7036] ORIENTALMOTOR/ VEXTA/ PK268M-E2.0B  /??DHL shipping!
? [7036] ORIENTALMOTOR/ VEXTA/ PK268M-E2.0B /??DHL shipping!
?[1278] VEXTA PK299-03B  / Fast Shipping!
?[1278] VEXTA PK299-03B / Fast Shipping!
?[10848] ORIENTAL MOTOR , VEXTA , ASM66AC-T20 , via DHL
?[10849] ORIENTAL MOTOR , VEXTA , ASM66AC-T20 , via DHL
?[10863] ORIENTAL MOTOR , VEXTA , PK268M-E2.0B , via DHL
?[10878] ORIENTAL MOTOR , VEXTA, PK268M-E2.0B, via DHL
?[10879] ORIENTAL MOTOR , VEXTA, PK268M-E2.0B, via DHL
?[10880] ORIENTAL MOTOR , VEXTA, PK268M-E2.0B, via DHL
?[10881] ORIENTAL MOTOR , VEXTA, PK268M-E2.0B, via DHL
0040-52760 / LIFT TO CATHODE ADAPTER / APPLIED MATERIALS AMAT / VEXTA
1 AXIS ACTUATOR CARRY WITH VEXTA C7214-9015
1 AXIS ACTUATOR CARRY WITH VEXTA C7214-9015
1 condition ASM66MC good pcs VEXTA in tested servo Motor
1 PC  Honeywell XCL5010 Controller Module In Good Condition
1 pc for the new VEXTA Oriental DRL42PB2G-04 stepper motor
1 pc for used VEXTA ASM69AC closed loop stepper motor
1 PC Honeywell XCL5010 Controller Module In Good Condition
1 PC new VEXTA MOTOR GFS4G30
1 pc NEW VEXTA Oriental Stepper Driver EZMC131-A
1 PC UDX5114 VEXTA stepper drive
1 PC USED ASD30A-A VEXTA stepper drive
1 PC Used HBLD25K VEXTA stepper driver
1 PC Used KBLD60-A VEXTA stepper driver
1 PC Used PK264A2-SG7.2 VEXTA stepper motor
1 PC Used UDK5114N VEXTA stepper driver
1 PC Used UI2120G VEXTA stepper driver
1 PC Used Vexta BXM460-GFH2 In Good Condition
1 PC Used Vexta KXPD30-CBZ In Good Condition
1 PC Used VEXTA PK569AE-A5
1 PC Used VEXTA Servo Motor ASM66MK-N5 In Good Condition
1 PC Vexta PK569BW Used
1 PC VEXTA PK599AW Motor Tested PK599AW
1 PC VEXTA Stepping motor ASM66AC-T7.2 Tested
1 pcs    new  VEXTA servo Motor ASM66AK-N10
1 pcs    new  VEXTA servo Motor ASM66AK-T7.2   
1 pcs    VEXTA   Motor  PH544-NB 
1 pcs    VEXTA   Motor  UPH596H-A   tested
1 pcs    VEXTA BXM5120-GFH2   motor 
1 pcs    VEXTA servo Motor ASM66AK-N10
1 pcs    VEXTA servo Motor PK543AN-TG30  tested
1 pcs  new  VEXTA stepper motor ASM66AA
1 pcs  new  VEXTA stepper motor ASM66AA-H50
1 PCS  NEW IN BOX VEXTA AXUD40C Governor
1 PCS  NEW IN BOX VEXTA driver ARLD16A-C
1 PCS  NEW IN BOX VEXTA driver BLHD15K
1 PCS  NEW IN BOX VEXTA driver CMD2109P
1 PCS  NEW IN BOX VEXTA driver CMD2112P
1 PCS  NEW IN BOX VEXTA driver UDK2120
1 PCS  NEW IN BOX VEXTA driver UDX5114
1 PCS  NEW IN BOX VEXTA motor AXHM230K-GFH
1 PCS  NEW VEXTA driver AXHD30K
1 PCS  NEW VEXTA driver AXHD50K
1 pcs  VEXTA   Motor  PH264-01  tested
1 pcs  VEXTA   Motor  PK266-02A new  in box
1 pcs  VEXTA   Motor  PK266-E2.0A   tested
1 pcs  VEXTA   Motor SD5114P  new in box
1 pcs  VEXTA  ASM36AK servo  motor      tested
1 pcs  VEXTA  driver UDK2120 new in  box
1 pcs  VEXTA  motor drive UDK5128N-M     tested   
1 pcs  VEXTA  Motor PK268-02B  new in  box
1 pcs  VEXTA motor 5-phase UPH569-AM-M8 stepper motor DC1.4A  tested
1 pcs  VEXTA Oriental Motor ASM66AA Closed Loop Controller  tested
1 pcs  VEXTA Oriental Motor Brushless DC Motor BXM230-GFS GFS2G10  tested
1 PCS  Vexta Oriental Motor BXD200A-A Driver Tested
1 pcs  VEXTA Oriental Stepper Drive ASD16B-C tested   
1 pcs  VEXTA servo  A5653-9215KTGM   tested   
1 pcs  VEXTA servo  ASM46MA  new  in  box
1 pcs  VEXTA servo  ASM46MA ASM46MA   tested   ok
1 pcs  VEXTA servo  ASM46MA-H50    tested   ok
1 pcs  VEXTA servo  ASM46MA-T3.6   tested   ok
1 pcs  VEXTA servo  motor  ARM911AC     tested   
1 pcs  VEXTA servo  motor  ASM911BC     tested   
1 pcs  VEXTA servo  motor  PK564AW-T10      tested   
1 pcs  VEXTA servo  motor ASM66MA    tested   
1 pcs  VEXTA servo  motor ASM66MA-P10    tested   
1 pcs  VEXTA servo  motor PK564AN-TG7.2   tested   ok
1 pcs  VEXTA servo  motor PK569NAW   tested   
1 pcs  VEXTA servo  motor PK569NAW   tested   ok
1 pcs  VEXTA servo Drive +ASD-C3    tested   
1 pcs  VEXTA servo Drive ASD24A-A new in  box
1 pcs  VEXTA servo Drive ASD24A-A-B1   tested   
1 pcs  VEXTA servo Drive ASD24C-A  new in  box
1 pcs  VEXTA servo Drive DFU1514W-M   tested   
1 pcs  VEXTA servo Motor  ASM66AK    tested
1 pcs  VEXTA servo Motor  PK564BW-T10   tested
1 pcs  VEXTA servo Motor  PK569AHW    tested
1 pcs  VEXTA servo Motor  PK596H-NAC tested
1 pcs  VEXTA servo Motor A6714-9015KHG    tested
1 pcs  VEXTA servo Motor ASM66AC-N36  tested
1 pcs  VEXTA servo Motor ASM66MC  tested