（1）PLC程序的正确性。
正确的程序必须能经得起系统运行实践的考验。
（2）PLC程序的可靠性。
能保证系统在正常和非正常（短时掉电、某些被控量标、某个环节有故障等）情况下都能安全可靠地运行。
能保证在出现非法操作（如按动或误触动了不该动作的按钮等）情况下不至于出现系统失控。
（3）PLC参数的易调整性好。
经常修改的参数，在程序设计时必须考虑怎样编写才能易于修改。
（4）PLC程序结构简练。
简练的程序，可以减少程序扫描时间、提高PLC对输入信号的响应速度。
（5）PLC程序的可读性好。
CINCINNATI MILLING MACHINE CO. DIR. VALVE 181692-D
MIGATRON TSR-1 NEW ULTRASONIC SENSOR WITH 50' CABLE TSR...
PRINCE PUMP SPD1B2008-1H2R NEW SPD1B20081H2R
NATIONAL INSTRUMENTS 182920-01 NEW PCI-DIO-96
SCHRADER BELLOWS CYCLONE 743048115 & MULTI 316061110
MODICON ASB824016 REMAN AS-B824-016
BARKSDALE PRESSURE SWITCH P1X-J85 NEW P1XJ85
MODICON AS-W801-012 3485-2400 REMAN W801012 34852400
ECLIPSE MODEL 106 ABP NEW 106ABP
SQUARE D 8903SQ02 LIGHTING CONTACTOR 8903SQ02
USON MEMORY MODULE 409-X300 REV.A REMAN 409X300REVA
MANNESMANN-REXROTH NT4 VTS0909-1X 00020208
MANNESMANN-REXROTH NT4 VTS0909-1X 00578875
MANNESMANN-REXROTH VTS0205-1X/DIB/E 00578877
MANNESMANN-REXROTH EA2 VTS06102X 00020251
MANNESMANN-REXROTH WM1 VTS0104-1X 00019935
VICKERS V20 1P6S 1A11 NEW PUMP V201P6S1A11
REXROTH 4WE6J51/AG24N9K4 AND 4WEH16E60/6AG24N9ETK4 ...
HONEYWELL UDC2300 REMAN DC230L-E0-10-0A00000-00-0
STI MINISAFE-B LIGHT CURTAIN NEW 23" TRANSMITTER
HONEYWELL MINI-PRO UDC2000 REMAN DC200H-0-000-1F0000-0
HONEYWELL MINI-PRO UDC2000 REMAN DC200H-0-000-1F0000-0
ASHCROFT D424B-XFS NEW PRESSURE CONTROL D424XFS
CHROMALOX TEMPERATURE CONTROL ARR-515 NEW ARR515
MiPC MONITOR MIPC-50M MIPC50M
ACME STANDARD POWER INC SPS 60-24/28 NEW SPS602428
LOVEJOY MOUNTING RING 697904-93416 NEW 69790493416
ALLEN BRADLEY 1398-SR3AF SER. B SHUNT ACTIVE RESISTOR
NORDSON 273378 10' HOSE
DFE TRUE TENSION INDICATOR TI 18B NEW TI18B
AMETEK DREXELBROOK 407-6000 SERIES LEVEL CONTROL
MAGNETROL LEVEL AND FLOW CONTROL T20-1B2A-AAP NIB
ALLEN BRADLEY 849A-Z0D24 SER. B RELAY 849AZ0D24
HONEYWELL V703 7D-1007-1 SERVO VALVE V7037D10071
MAGNETEK SPB2-6-WA PUSH BUTTON PENDANT NEW SPB26WA
LAMB ELECTRIC 115330 VACUUM MOTOR NIB
CLEVELAND KIDDER MWI-13261 NEW MWI13261
BALDOR VM3542 NEW 3/4 HP MOTOR VM3542
ADVANCE 79W4091-001 NEW BALLAST 79W409100
TELEMECANIQUE TSX17ACCPC NEW PC-TSX17 PROGRAMMING KIT T...
COMAIR ROTRON 031009 FAN NEW 031009
FAFNIR BEARINGS 2MM306WI CR DUL NEW 2MM306WICRDUL
ECLIPSE DC2005-0-0000-FC30-EI-0122 NEW CONTROLLER
DURANT EATON 57601-400 TOTALIZER NEW 57601400
NAMCO EB700-60501 SOLENOID NEW EB70060501
TELEMECANIQUE REVERSING CONTACTOR LC2-D1201-B7 NEW LC2D...
SOLA/HEVI-DUTY 83-24-260-3 NEW 83242603
USON 432A301B TRANSDUCER CONVERTER 432A301B
FESTO MFHE-3-1/2 NEW SOLENOID VALVE MFHE312
LINCOLN SRN4H0.75T61 ELECTRIC MOTOR NEW SRN4H0.75T61
FANUC A20B-2902-0070 / 02B A20B2902007002B
R & I MFG. ACTUATOR DURA-SCAPE BC-2B NEW BC2B
THOMSON BALL BUSHING LINEAR BEARING XA406080 NEW
TSXDSY16R5 OUTPUT MODULE TSXDSY16R5
UNIVERSAL TOOLS UT8001 3/8" ANGLE NUT RUNNER UT800...
GE FANUC IC693PWR322E NEW POWER SUPPLY
ALLEN BRADLEY 700-NM600A1 NEW RELAY 700NM600A1
MODICON 140 DAI 543 00 SEALED 140DAI54300
HYDAC TRANSDUCER HDA-3775-A-250-000 NEW HDA3775A250000
EFECTOR PN5204 NEW PRESSURE SWITCH PN5204
SIEMENS MODULE DIGITAL INPUT 505-4332 NEW 5054332
TSX PREMIUM TSXCXP213 NEW 8FT CABLE TSXCXP213
BALANCE ENGINEERING BMDA-110 PC BOARD BMDA110
HONEYWELL MICRO SWITCH PHOTOELECTRIC SENSOR FE-MLS 8C N...
