PLC的基本工作方式是顺序执行用户程序,每一时钟周期执行一条指令。对用户程序的执行一般有循环扫描和定时扫描两种,扫描过程分为三个阶段,即输入采样阶段、程序执行阶段和输出刷新阶段,如图1所示。
(1)输入采样阶段。PLC在输入采样阶段以扫描方式顺序读人所有输入端子的状态,存人输人寄存器,接着转入程序执行阶段。
(2)程序执行阶段。PLC在程序执行阶段中顺序对每条指令进行扫描。先从输人寄存器读人所有输入端子的状态。
AEG Model FK60-04 Tube Contain in Philips Mount
Miyachi Unitek: 250DP Dual Pulse Stored Energy Supply.
Veeco Model: FPP5000 Four Point Probe W2
Miyachi Unitek 125DP. Dual Pulse Resistance Welding Pow
HASKEL AGT 32/152 GAS BOOSTER TWO STAGE PUMP AGT32/152
EUROTHERM TU1471 Single Phase SCR Power Controller =R
Advanced Energy (AE) 3152012-002W MDX Magnatron Drive
Bayside Motion Group Model: RD180-030-002 Multidrive Pl
Asco Model: H118AN132F1/ Hydramotor Gas Fuel Actuator
Vector Corporation Tablet Tester (N63712) with Mettler
ESEC Model: 710-6-5 Wafer Mounter
Centigram: 70 Voice Mail w/(2) 2410-0226-17 Port Cards
Dionex Model: AS3500 Inert Variable-Loop Autosampler w/
Sigma Instruments Sigmatic Thickness Guage
Schmidt Press Model: 29-097-99 4 Stroke, 7000 Pound Pre
Century Systems Model: OVA-128 Organic Vapor Analyzer
Tektronix Model: VX4244, 16 Channel Digitizer
Reliance Electric MaxPak Plus: 1GAX04493. VS Spindal D
Axcelis / Eaton: 0475-0010-0001 Magnet Exit Bellows
Miyachi Unitek Model 250 Watt Seconds Welder Power Supp
EUROTHERM TU1451 Single Phase SCR Power Controller =R
WENTORTH LABS CMP-100 CMP100 WAFER PROBER TEST
Adept Technology Dual C AMP Module, P/N: 10338-53005
Varian Model: 990-CLD Auto-Line Helium Leak Rate Dectec
温馨提示:为规避购买风险,建议您在购买产品前务必确认供应商资质及产品质量。