可编程控制器（programmable logical controller，简称PLC）已经越来越多地应用于工业控制系统中，并且在自动控制系统中起着重要的作用。所以，对PLC的正确选择是重要的。
面对众多生产厂家的各种类型PLC，它们各有X缺点，能够满足用户的各种需求，但在形态、组成、功能、网络、编程等方面各不相容，没有一个统一的标准，无法进行横向比较。下面提出在自动控制系统设计中对PLC选型的一些看法，可以在挑选PLC时作为参考。
可以通过以下几方面的比较，挑选到适合的产品。
这一点尤为重要。在自动控制系统设计之初，就应该对控制点数（数字量及模拟量）有一个准确的统计，这往往是选择PLC的X要条件，一般选择比控制点数多10%~30%的PLC。这有几方面的考虑：
1、可以弥补设计过程中遗漏的点；
2、能够保证在运行过程中个别点有故障时，可以有替代点；
3、将来增加点数的需要。
工作环境是PLC工作的硬性指标。自控系统将人们从繁忙的工作和恶劣的环境中解脱出来，就要求自控系统能够适应复杂的环境，诸如温度、湿度、噪音、信号屏蔽、工作电压等，各款PLC不尽相同。一定要选择适应实际工作环境的产品。
ABB MODEL YB560103-BD/4 DIGITAL I/O BOARD DSQC223
ABB MODEL DSQC266A 3HAB8796-1/2B PROCESSOR BOARD
ABB MODEL DSQC129 YB161102-BV/1 CONVERTER CARD
ABB MODEL 3HAB2211-1 DSQC256A CONTROL BOARD
ABB Memory Board DSQC 317 #28968
ABB Measuring Card 3BSE004940RI 10564992
ABB Main Circuit Interface Board 61431390B 1/410564947
ABB Kent-Taylor 200RB30002C Micro-Scan 200 Controller 2400
ABB IRC5 DSQC 652 I/O card 24VDC 3HAC025917-001
ABB I/O Module Part# DSQC-239
ABB GNT0164200R0003 PG6320 Wiring Board 3200
ABB GNT0164200R0002 PG6310 Wiring Board 8000
ABB GME PC Board DSQC 236G YB560103-CD/24 56M009G
ABB Freelance2000 备件 DAO01 1pcs
ABB Ethernet Communication 3HNE00001 DSQC336 #29412
ABB Elmo Servo Motor PS90/6-38-P-LSS?-3822
ABB ELEC. TRANSMITTER 503TB01261A0120?-1000-804216
ABB EHW550C-1L11 SIZE 6 WELDING ISOLATION CONTACTOR
ABB EHW250WC2P-1L SIZE W5 WELDING CONTACTOR NIB
ABB E3HAB2231-1 DSQC 314C Rectifier DC link
ABB E3HAB2209-1 DSQC 306 Computer board
ABB DSQC336 3HNE00001 ETHERNET 3HNE 00001 NETWORK I/O
ABB DSQC331 Robot Panel Unit
ABB DSQC327 3HAB 7203-1 MODULE DSQC327 3HAB72301
ABB DSQC325 3HAB2241 SERVO ROBOT I/O 3HAB2241-1
ABB DSQC322 3HAB5960 SERVO ROBOT I/O 3HAB5960
ABB DSQC314B REMAN. DSQC 314B
ABB DSQC303 3HAA3573-ADA ROBOT 3HAA3573ADA DSQC 303
ABB DSQC266T 3HAB8802-1/2B ROBOT SERVO 3HAB880212B
ABB DSQC266T 3HAB-8802-1/2B
ABB DSQC266G 3HAB-8801-1/2B
ABB DSQC266C 3HAB-8798-1/2B
ABB DSQC266B 3HAB-8797-1/2B
ABB DSQC266A 3HAB-8796-1/2B
ABB DSQC258 3HAA3563-AUA/1
ABB DSQC258 3HAA3563-AUA
ABB DSQC257 3HAA3563-ATA
ABB DSQC256A 3HAB2211-1/1
ABB DSQC256A 3HAB2211-1/1
ABB DSQC255 YB53HAA3563-ARA
ABB DSQC254 3HAA3563-APA
ABB DSQC253 3HAA3563-AMA/0
ABB DSQC-252 3HAA 3563-ALA/2 PC Board
ABB DSQC-249B SERVO AMPLIFIER, tested, warranty
ABB DSQC249B 3HAA3563-AHA/3
ABB DSQC249B 3HAA3563-AHA/1
ABB DSQC249A YB560103-AGA/3
ABB DSQC-239 YB560103-CH/10 REMOTE I/O BOARD DSQC239
ABB DSQC-239 I/O BOARD REMOTE, tested, warranty
ABB DSQC237+41 YB560103-CF/1
ABB DSQC236U AXIS DRIVE BOARD 3HAA-3563-ANA
ABB DSQC236T YB560103-CE/024
ABB DSQC236T AXIS DRIVE BOARD YB560103-CE
ABB DSQC-236T AXIS CONTROLLER BOARD, tested, warranty
ABB DSQC-236G YB560103-CD/22 DRIVE BOARD DSQC236G
ABB DSQC236G YB560103-CD/024
ABB DSQC-236G MODULE YB560103-CD/24
ABB DSQC236G AXIS DRIVE BOARD YB560103-CD
ABB DSQC-236G AXIS CONTROLLER BOARD, tested, warranty
ABB DSQC236D 3HAB-2207-1/3
