[毕业设计精品]用plc技术设计五层电梯控制系统毕业设计

1用PLC技术设计五层电梯控制系统毕业设计A1A2A3A4A0A5A6A7A8A9A10A11A12A13A14A15A16A17A18A19A20A22PLCA23A21A24A25A16A26A27A28A29A27A31A32A30A33A35A7A34A36A37A38A39A40A23A21A42A43A41A44A3A14A15,A10A11A45,PLC,A26A27,A29A271A47A46A49A48A50A51A52A53A54A55A56A57A58A59A60A61A52A62A55A56A63A64A59A65A66A67A68A60A61A52A62A69A70A71A72A73A54A74A75A76A77A78A79A80A81A54A82A83A84A85A86A55A87A88A59A89A90A91A65A92A93A94A95A54A90A65A96A97A98A99A100A101A65A66A102A103A104A105A87A88A68A106A107A108A88A79A109A110A102A103A108A88A101A106A107A108A88A54A111A112A113A65A66A114A115A116A117A118A54A119A120A121A122A48A123A124A125A126A59A127A109A110A102A103A108A88A128A89A65A66A129A130A87A131A114A115A54A132A133A101A134A53A135A136A137PLCA102A103A138A139A140A106A107A104A105A59A141A142A65A143A144A107A145A144A146A147A148A149A150A102A103A59A77A122A96A151A54A152A153A111A79A154A155A111A1012A65A66A102A103A104A105A156A157A158A159A65A66A102A103A104A105A156A157A160A161A162A163A164A165A144A166A167A168A169A144PLCA144A138A139A140A106A107A104A105A158A159A59A102A103A104A105A94A158A170A171A1701A172A173A101A170A69A138A139A140A174A175A159A106A107A176A112A59A127A109A110A102A103A108A88A89A160PLCA175A159A54A101PLCA177A178A179A180A181A182A168A169A54A109A110A132A104A59A183A127A184A138A139A140A57A185A186A187A168A169A59A188A116A138A139A140A189A190A134A191A54A76A67A192A193A194A195A196PLCA59A197A159A198A184A199A200A132A104A101A104A105A201A202A203A204A205A65A206A90A188A207A208A209A54A210A211A212A213A140A214PGA215A59A175A159A107A145A216A217A214A218A219A59A197A159A107A145A149A150A79A146A203A149A150A101A220A221A104A105A201A222A223A202A203A103A206A65A224A59A225A65A66A226A107A114A115A116A59A65A206A90A179A227A228A84A57A65A192A193A59A184A138A139A140A229A219A65A112A59A230A103A71A143A65A231A72A60A101A134A53A135A65A66A68A232A61A233A234A235A137A54A74A143A65A66A59A236A237A88A238A87A239A104A105A194A240A168A169A6826A241A59A242A243A244A245A144A76A67A192A193A246A247A144A248/A132A167A102A103A144A146A203A216A217A144A249A66A144A107A145A102A103A250A101A194A185A168A16921A241A59A242A243A248/A132A167A144A251A115A144A252A115A144A102A103A138A139A140A168A169A144A253A254A140A144A255A173A220A250A101A222A0A1A251A2A3A246A247A148A4FX2A22864MRPLCA101A138A139A140A246A137A129A11616G5CIMRG5A4022A75A137A138A139A140A59A230A5A6A111A68A87A71A209A102A103A74A143A23A7A65A206A90A54A65A143A59A235A65A206A90A244A8A9A60A54A194A185A211A157A120A137A227A181A182A104A137A10A95A59A241A12A107A252A141A142A217A13A186A206A14A15A16A17A18A19A54A114A115A250A54A20A206A106A21A176A112A87A235A181A182A65A206A90A22A24A60A111A112A54A102A103A250A190U/FA102A103A144A25A26A102A103A144A149A150U/FA102A103A144A149A150A25A26A102A103A232A182A102A103A27A28A29A68A96A97A59A17A69A149A150A25A26A102A103A30A120A95A65A66A102A103A124A31A101A210A211A212A213A140A205A32A65A206A90A188A207A208A209A59A75A237PGA215A33A34A212A213A140A208A209A35A113A65A206A90A217A107A79A218A219A65A66A54A146A203A101A246A137OMRONA234A36A541024A37A206A63A26A28A38A65A37A39A210A211A212A213A140A101A210A211A212A213A140A205A65A206A90A188A207A208A209A59A99A84AA144BA40A93A37A39A101A225AA93A37A39A41A42A227BA93A37A3990A145A116A59A43A68A65A206A90A179A227A44A211A192A193A225AA93A37A39A45A46A227BA93A37A3990A145A116A59A43A68A65A206A90A179A227A218A211A192A193A101A222A0AA144BA93A37A39A54A93A47A59A87A48A56A65A206A90A54A211A184A101A222A0AA144BA37A39A54A139A49A50A51A52A87A217A53A65A206A90A54A211A107A101A54A1AA144BA93A37A39A54A42A55A50A46A55A99A84A135A56A37A39A59A87A1A197A159A152A153A44A184A146A147A79A218A184A146A147A54A37A39A47A57A101A210A211A212A213A140A190A220A37A39A194A185A196PGA215A59PGA215A228A190A220A218A219A168A169A195A196A138A139A140A59A1A58A59A115A114A60A106A61A1013A65A66A54A76A67A237A622A63A64A65A66A147A67A68A69A70A71A72A73A74A80A75A76A63A77A78A79A81A77A82A83A84A69A70A85A86A84A87A88A68A71A72A89PLCA179A90A91A251A92A93A94A95A96A97A64A98A68A99A100A140A101A82A133A102A96A103A105A106A68A107A108A140A101A109A110A111A112A96A113A114A115A68A116A117A140A101A73A203A118A119A120A121A175A122A123A124A125A126A127A128A129A130A211A131A132A134PLCA135A136A137A138A145A139A141A131A142A143A129A144A146A148A149A150A151A152A137A122A153A154A148A155A156A176A155A158A159A155A193A159A155A122A153A139A132A176A160A128A142A143A161A162A163A127A176A164A165A181A166A185A181A131A132A167A168A159A131A132A142A143A169A170A146A134A127A176A164A171A172A1730HZA25450HZA171A172A174A176A134A174A176A146A177A1353SA178A180A134A182A124A183A23650HZA129A159A184A186A187A122A153A134A188A189A174A176A167A122A153A190A129A191A192A161A194A195A159A142A143A254A196A124A134PLCA197A198A168A159A142A143A134A144A146A136A137A199A153A142A143A134A200A146A199A153A129A136A137A150A201A2026HZA161A17350HZA2546HZA129A193A159A204A118A1353SA205A206A188A189A134A194A207A2546HZA159A184A146A127A128A160A208A193A159A134A245A209A200A159A184A199A153A161A194A210A212A142A143A254A196A124A134PLCA197A198A199A153A142A143A134A144A146A152A137A160A128A142A143A134A200A146A127A176A164A1736HZA193A159A2540HZA134A127A128A160A128A161A165A213A214A215A216A134A135A218A219A174A176A155A122A153A155A193A159A199A153A190A206A134A149A150A151A129A221A159A136A137A223A186A187A224A225A226A129A134A193A2270HZA205A124A134A221A159A136A137A223A121A171A134A229A204PLCA231A232A167A233A176A171A234A134A127A128A122A153A237A238A239A2402A242A145A161A2402A243A122A153A237A238A244A229A204A149A150A151A246A153A247A248A134A249A244A229A204A252A248A122A153A237A238A136A253A255A161A114A0A1A2A3A149A150A151A246A153A78A4A247A248A79C1013S,A247A248A158A159A174A176A146A177A2023SA79C1023S,A247A248A193A159A146A177A2023SA79D10250HZ,A247A248A80A5A122A153A159A184D1036HZA134A247A248A199A153A159A184A1614A127A128A122A153A243A15A248A142A143A129A6A7A192A202A186A19A81A72A191A8A134A135A15A82A149A81A216A134A83A9A10A111A11A244A12A13A14A16A122A153A210A17A155A101A84A103A18A155A160A12A85A249A161A2A3A149A150A151A116A159A20A225A21A131A132A244A86A114A87A22A9A10A161A135A241A23A158A27A24A127A89A129A86A25A216A134A91A3A126A169A129A26A181A28A29A151A135A30A189A159A184A225A21A129A144A146A134A249A244A30A189A15A248A225A21A131A132A1613目录一PLC的简介311PLC的概念312PLC的发展阶段413PLC的组成及工作原理514PLC的特点及功能9二电梯的概述1121电梯的定义1122电梯的分类1123电梯的主要机械部件12三电梯的电力驱动系统1431电梯电力驱动系统的定义及构成1432电梯电力驱动系统的要求1433交流感应电动机的转速调节及其评价1434交流调速电梯的运行工艺过程1535交流双速电梯的主驱动系统1636三相交流双速异步电动机的拽引系统17四PLC在电梯控制中的应用1841电梯的启动所需条件1842电梯停车所需的条件1843设备选型1844电梯控制系统原理框图1845输入输出分配表1946程序的编写21结束语27致谢28参考文献314一PLC的简介11、PLC的概念可编程控制器PROGRAMMABLELOGICCONTROLLER简称PLC或PC，在现代工业控制中占有重要地位。G7424文G4557其G3534G11796G11705G16794G17839行简要介G13473。可编程控制器G708PROGRAMMABLECONTROLLERG709G7171G16757G12651机G4490G7075中的一G2604，G7171G1038工业控制应用G13792设G16757制G17908的。G7101G7411的可编程控制器称作可编程G17935G17765控制器G708PROGRAMMABLELOGICCONTROLLERG709，简称PLC，G4439主要用G7481代G7379G13499电器G4466现G17935G17765控制G19555G11540G6228G7427的发展G17837G12193G16025G13634的功能G5062G13475G3835G3835G17241过G1114G17935G17765控制的G14551G3272，G3252G8504，G1182G3837G17837G12193G16025G13634称作可编程控制器，简称PC。G1306G7171G1038G1114G18003G1825G994G1022G1166G16757G12651机G708PERSONALCOMPUTERG709的简称G9163G9114，所G1209G4570可编程控制器简称PLC。G3281G19481电工G4008G2604G1262G708IECG709G1820G2530G20053G5079G1114PLCG7643G1946的G14621G7708G12544一G12307，G12544二G12307，G5194在1987G51922G7388G17902过G1114G4557G4439的定义G726G256可编程控制器G7171一G12193G6980G4395运G12651G6817作的电G4388系统，G999G1038在工业G10627G3671应用G13792设G16757的。G4439G18331用一类可编程的G4396G1660器，用G1122其G1881部G4396G1660程序，G6203行G17935G17765运G12651，G20046序控制，定G7114，G16757G6980G994G12651G7427G6817作G12573G19766G2533用G6155的G6363G1208，G5194G17902过G6980G4395或G8181G6323G5347输入/输出控制G2520G12193类型的机械或G10995G1147过程。可编程控制器及其有G1863G3818部设备，G18129G6365G7143G1122G994工业控制系统G13864成一G1022G6984G1319，G7143G1122G6205G1817其功能的原G2029设G16757。G257PLCG19394G1002G1209G7481，G4625G12661G7114G19400G993G19283，G1306发展G17817速。G1038G1114G1363其G10995G1147G2656发展G7643G1946G2282，美G3281电气制G17908商协G1262NEMAG708NATIONALELECTRICALMANUFACTORYASSOCIATIONG709G13475过四G5192的调查工作，G11221984G5192首G1820G4570其正G5347命名G1038PCG708PROGRAMMABLECONTROLLERG709，G5194给PC作G1114如下定义“PCG7171一G1022G6980G4395G5347的电G4388G16025G13634，G4439G1363用G1114可编程序的记忆G1319G1660G4396G6363G1208。用G7481G6203行诸如G17935G17765，G20046序，G16757G7114，G16757G6980G994演G12651G12573功能，G5194G17902过G6980G4395或类似的输入/输出G8181块，G1209控制G2520G12193机械或工作程序。一部G6980G4395电G4388G16757G12651机若G7171从事G6203行PC之功能G11540，亦被视G1038PC，G1306G993包括鼓G5347或类似的机械G5347G20046序控制器。G257G19555G11540微处理器、G16757G12651机G2656G6980G4395G17902信G6228G7427的飞速发展，G16757G12651机控制G5062G13475G6205展到G1114几乎所有的工业领域。当前用G1122工业控制的G16757G12651机可G1209分G1038几类，类如可编5程序控制器、G3534G1122PC总线的工业控制G16757G12651机、G3534G1122单片机的测控G16025G13634、用G1122G8181G6323量闭G10627控制的可编程调节器、集散控制系统G708DCSG709G2656现场总线控制系统G708FCSG709G12573。PLC的应用广、功能强G3835、G1363用方便，G7171现代工业自动G2282的主要设备之一。PLCG5062G13475广泛地应用在G2520G12193机械设备G2656G10995G1147过程的自动控制系统中，PLC在其他领域，例如民用G2656G4490庭自动G2282的应用也得到G1114G17817速的发展。12、PLC的发展阶段虽然PLCG19394G1002G7114G19400G993G19283，G1306G7171G19555G11540微处理器的出现，G3835规G8181、G17241G3835规G8181集成电路G6228G7427的G17817速发展G2656G6980据G17902讯G6228G7427的G993断G17839步，PLC也G17817速发展，其发展过程G3835致可分三G1022阶段G7261早期的PLC（60年代末70年代中期）G7101G7411的PLC一般称G1038可编程G17935G17765控制器。G17837G7114的PLC多少有点G13499电器控制G16025G13634的G7379代物的含义，其主要功能只G7171G6203行原G1820由G13499电器完成的G20046序控制、定G7114G12573。G4439在硬件上G1209G1946G16757G12651机的形G5347出现，在I/O接口电路上作G1114改G17839G1209适应工业控制现场的要求。G16025G13634中的器件主要G18331用分立元件G2656中小规G8181集成电路，G4396G1660器G18331用磁芯G4396G1660器。另G3818还G18331取G1114一些措施，G1209提高其抗干扰的能力。在软件编程上，G18331用广G3835电气工程G6228G7427G1166G2604所熟悉的G13499电器控制线路的方G5347梯形图。G3252G8504，G7101G7411的PLC的性能要优G1122G13499电器控制G16025G13634，其优点包括简单G7143懂，便G1122安G16025，G1319积小，能耗低，有故障G6363G1363，能重复G1363用G12573。其中PLC特有的编程语言梯形图一直沿用至G1182。2中期的PLC（70年代中期80年代中后期）在70G5192代微处理器的出现G1363PLC发G10995G1114巨G3835的变G2282。美G3281，日G7424，德G3281G12573一些厂G4490G1820G2530开始G18331用微处理器作G1038PLC的中央处理单元G708CPUG709。6G17837样，G1363PLC得功能G3835G3835G3698强。在软件方G19766，G19512G1114G1457G6357其原有的G17935G17765运G12651、G16757G7114、G16757G6980G12573功能G1209G3818，还G3698G2164G1114G12651G7427运G12651、G6980据处理G2656G1268G17877、G17902讯、自G16798断G12573功能。在硬件方G19766，G19512G1114G1457G6357其原有的开G1863G8181块G1209G3818，还G3698G2164G1114G8181G6323量G8181块、G17840程I/OG8181块、G2520G12193特G8542功能G8181块。G5194G6205G3835G1114G4396G1660器的G4493量，G1363G2520G12193G17935G17765线G3292的G6980量G3698G2164，还提G1391G1114一定G6980量的G6980据G4504G4396器，G1363PLC得应用G14551G3272得G1209G6205G3835。3近期的PLC（80年代中后期至今）G17839入80G5192代中、G2530G7411，由G1122G17241G3835规G8181集成电路G6228G7427的G17817速发展，微处理器的G5078场价G7696G3835G5145G5242下G17312，G1363得G2520G12193类型的PLC所G18331用的微处理器的当G8437G7234G17953提高。G13792G1000，G1038G1114G17839一步提高PLC的处理速G5242，G2520制G17908厂商还G13451G13451G11752制开发G1114G999用G17935G17765处理芯片。G17837样G1363得PLC软、硬件功能发G10995G1114巨G3835变G2282。13、PLC的组成及工作原理PLC各组成部件及作用1CPU是PLC的核心部分。G994G17902用微机CPU一样，CPU在PC系统中的作用类似G1122G1166G1319的G12082G13475中G7542。其功能G7261用G6207G6563方G5347G708G2530G19766介G13473G709接G6922现场输入G16025G13634的G10378G5589或G6980据，G5194G4396入输入G7156G16949G4504G4396器或G6980据G4504G4396器G7272接G6922G5194G4396G1660从编程器输入的用G6155程序G2656G6980据G7273G16798断电G9316G2656PCG1881部电路的工作G10378G5589及编程过程中的语G8873G19181G16835G7274在PCG17839入运行G10378G5589G2530G7267AG6203行用G6155程序G1147G10995相应的控制信G2507G708从用G6155程序G4396G1660器中G17892条G16847取G6363G1208，G13475命G1208G16311G18334G2530，G6365G6363G1208规定的G1231G2165G1147G10995相应的控制信G2507，G2447启闭有G1863的控制电路G709BG17839行G6980据处理分G7114、分G9204G17959地G6203行G6980据G4396取、G1268G17877、组G2524、G8616G17751、变G6454G12573动作，完成用G6155程序中规定的G17935G17765或G12651G7427运G12651G1231G2165CG7368G7044输出G10378G5589输出G4466施控制G708G7693据运G12651结G7536，G7368G7044有G1863G7643G5547位的G10378G5589G2656输出G7156G16949G4504G4396器的G1881G4493，G1889由输入G7156G16949G4504G4396器或G6980据G4504G4396器的G1881G4493，G4466现输出控制、制表、G6183G2372、G6980据G17902讯G12573G7092存储器系统程序G4396G1660器G4396G6930系统工作程序G708G11429控程序G709、G8181块G2282应用功能G4388程序、命G1208、G16311G18334、功能G4388程序的调用G12661理程序G2656系统参G6980，G993能由用G6155直接G4396取。用G6155程序G4396G1660器G4396G6930用G6155程序。G2375用G6155G17902过编程器输入的用G6155程序，可G1209由用G6155直接G4396取。功能G4396G1660器G708G6980据G2318G709G4396G6930用G6155G6980据PC的用G6155G4396G1660器G17902G5132G1209G4395G70816位/G4395G709G1038单位G7481表G12046G4396G1660G4493量。G8892G5859G726系统程序直接G1863系到PC的性能，G993能由用G6155直接G4396取，所G1209，G17902G5132PCG1147G2709G17176G7021中所G6363的G4396G1660器形G5347或G4396G1660方G5347及G4493量，G7171G6363用G6155程序G4396G1660器G13792言。3I/O输入/输出部件（I/O模块接口电路、I/O映像存储器）I/O输入/输出部件CPUG994现场I/OG16025G13634或其他G3818部设备之G19400的G17842接部件。PLC提G1391G1114G2520G12193G6817作电G5191G994驱动能力的I/OG8181块，G1209及G2520G12193用G17896的I/O组件G1391用G6155选用G72681输入/输出电G5191转G64542电气G19560G121753G1030/G5194行转G64544G6980据G1268G178775A/D、D/A转G64546G16835G11733G7669G205767其他功能G8181块8I/OG8181块可G994CPUG6930在一G17227，也可G17840程G6930G13634。G17902G5132，I/OG8181块上还G1867有G10378G5589G7186G12046G2656I/O接线G12483G4388G6502。4编程器等外部设备编程器PLC开发应用、G11429测运行、G7828查G13512G6264G993可G13582少的工G1867作用G7261用G1122用G6155程序的编制、编G17765、调G16809、G7828查G2656G11429视2G17902过G19202G11436G2656G7186G12046器G2447G7828测PLCG1881部G10378G5589G2656参G69803G17902过G17902讯G12483口G994CPUG13864系，G4466现G994PLC的G1166机G4557G16817分类G7261简单型只能G13864机编程G727只能用G6363G1208G9177单编程2G7246能型G7094可G13864机G708ONLINEG709，也可G14085机G708OFFLINEG709编程G727可G1209G18331用G6363G1208G9177单G708语G2489表G709、梯形图G12573语言编程。G5132可直接G1209电G14053作G1038编程器，安G16025相G1863的编程软件编程G8892G5859G726编程器G993直接G2164入现场控制运行。一G2500编程器可开发、G11429G6264G16780多G2500PLC的工作。其他G3818设G726磁G11436、G1821G11436、EPROM写入器G708用G1122G3278G2282用G6155程序G709、G6183G2372机、图形9G11429视系统或上位G16757G12651机G12573G12573。5电源G1881部电G9316开G1863G12295G2399电G9316，G1391G1881部电路G1363用G727G3835多G6980机型还可G1209G2533G3818提G1391DC24VG12295G2399电G9316，G1038现场的开G1863信G2507、G3818部G1268感器G1391电。G3818部电G9316可用一般工业电G9316，G5194备有G19158电G8756G708备用电G8756G709，G1363G3818部电G9316故障G7114G1881部重要G6980据G993致G1014G3845。1PLC的工作原理G7380G2033G11752制G10995G1147的PLC主要用G1122代G7379G1268统的由G13499电器接G16314器构成的控制G16025G13634，G1306G17837G1016G13785的运行方G5347G7171G993相G2528的G726G13499电器控制G16025G13634G18331用硬G17935G17765G5194行运行的方G5347，G2375如G7536G17837G1022G13499电器的线G3292G17902电或断电，G16825G13499电器所有的G16314点G708包括其G5132开或G5132闭G16314点G709在G13499电器控制线路的G2750G1022位G13634上G18129G1262立G2375G2528G7114动作。PLC的CPUG2029G18331用G20046序G17935G17765G6207G6563用G6155程序的运行方G5347，G2375如G7536一G1022输出线G3292或G17935G17765线G3292被接G17902或断开，G16825线G3292的所有G16314点G708包括其G5132开或G5132闭G16314点G709G993G1262立G2375动作，G5529G20047G12573G6207G6563到G16825G16314点G7114G6177G1262动作。G1038G1114G9052G19512二G13785之G19400由G1122运行方G5347G993G2528G13792G17908成的G5058异，考G15397到G13499电器控制G16025G13634G2520类G16314点的动作G7114G19400一般在100MSG1209上，G13792PLCG6207G6563用G6155程序的G7114G19400一般G3355小G1122100MS，G3252G8504，PLCG18331用G1114一G12193G993G2528G1122一般微型G16757G12651机的运行方G5347G6207G6563G6228G7427。G17837样在G4557G1122I/OG2721应要求G993高的场G2524，PLCG994G13499电器控制G16025G13634的处理结G7536上G4613没有什么G2318别G1114。1输入G18331样阶段G726在输入G18331样阶段，PLCG1209G6207G6563方G5347依G8437地G16847入所有输入G10378G5589G2656G6980据，G5194G4570G4439们G4396入I/OG7156G16949G2318中的相应得单元G1881。输入G18331样结束G2530，转入用G6155程序G6203行G2656输出刷G7044阶段。在G17837G1016G1022阶段中，G2375G1363输入10G10378G5589G2656G6980据发G10995变G2282，I/OG7156G16949G2318中的相应单元的G10378G5589G2656G6980据也G993G1262改变。G3252G8504，如G7536输入G7171脉冲信G2507，G2029G16825脉冲信G2507的宽G5242G5529G20047G3835G1122一G1022G6207G6563周G7411，G6177能G1457证在G1231何情况下，G16825输入G3355能被G16847入。2用G6155程序G6203行阶段G726在用G6155程序G6203行阶段，PLC总G7171G6365由上G13792下的G20046序依G8437地G6207G6563用G6155程序梯形图。在G6207G6563每一条梯形图G7114，又总G7171G1820G6207G6563梯形图左边的由G2520G16314点构成的控制线路，G5194G6365G1820左G2530右、G1820上G2530下的G20046序G4557由G16314点构成的控制线路G17839行G17935G17765运G12651，然G2530G7693据G17935G17765运G12651的结G7536，刷G7044G16825G17935G17765线G3292在系统RAMG4396G1660G2318中G4557应位的G10378G5589G727或G13785刷G7044G16825输出线G3292在I/OG7156G16949G2318中G4557应位的G10378G5589G727或G13785确定G7171否要G6203行G16825梯形图所规定的特G8542功能G6363G1208。G2375，在用G6155程序G6203行过程中，只有输入点在I/OG7156G16949G2318G1881的G10378G5589G2656G6980据G993G1262发G10995变G2282，G13792其他输出点G2656软设备在I/OG7156G16949G2318或系统RAMG4396G1660G2318G1881的G10378G5589G2656G6980据G18129有可能发G10995变G2282，G13792G1000G6502在上G19766的梯形图，其程序G6203行结G7536G1262G4557G6502在下G19766的凡G7171用到G17837些线G3292或G6980据的梯形图G17227作用G727相反，G6502在下G19766的梯形图，其被刷G7044的G17935G17765线G3292的G10378G5589或G6980据只能到下一G1022G6207G6563周G7411G6177能G4557G6502在其上G19766的程序G17227作用。2PLC的扫描技术当PLC投入运行G2530，其工作过程一般分G1038三G1022阶段，G2375输入G18331样、用G6155程序G6203行G2656输出刷G7044三G1022阶段。完成上述三G1022阶段称作一G1022G6207G6563周G7411。在G6984G1022运行G7411G19400，PLC的CPUG1209一定的G6207G6563速G5242重复G6203行上述三G1022阶段。1输入G18331样阶段G726在输入G18331样阶段，PLCG1209G6207G6563方G5347依G8437地G16847入所有输入G10378G5589G2656G6980据，G5194G4570G4439们G4396入I/OG7156G16949G2318中的相应得单元G1881。输入G18331样结束G2530，转入用G6155程序G6203行G2656输出刷G7044阶段。在G17837G1016G1022阶段中，G2375G1363输入G10378G5589G2656G6980据发G10995变G2282，I/OG7156G16949G2318中的相应单元的G10378G5589G2656G6980据也G993G1262改变。G3252G8504，如G7536输入G7171脉冲信G2507，G2029G16825脉冲信G2507的宽G5242G5529G20047G3835G1122一G1022G6207G6563周G7411，G6177能G1457证在G1231何情况下，G16825输入G3355能被G16847入。112用G6155程序G6203行阶段G726在用G6155程序G6203行阶段，PLC总G7171G6365由上G13792下的G20046序依G8437地G6207G6563用G6155程序G708梯形图G709。在G6207G6563每一条梯形图G7114，又总G7171G1820G6207G6563梯形图左边的由G2520G16314点构成的控制线路，G5194G6365G1820左G2530右、G1820上G2530下的G20046序G4557由G16314点构成的控制线路G17839行G17935G17765运G12651，然G2530G7693据G17935G17765运G12651的结G7536，刷G7044G16825G17935G17765线G3292在系统RAMG4396G1660G2318中G4557应位的G10378G5589G727或G13785刷G7044G16825输出线G3292在I/OG7156G16949G2318中G4557应位的G10378G5589G727或G13785确定G7171否要G6203行G16825梯形图所规定的特G8542功能G6363G1208。G2375在用G6155程序G6203行过程中，只有输入点在I/OG7156G16949G2318G1881的G10378G5589G2656G6980据G993G1262发G10995变G2282，G13792其他输出点G2656软设备在I/OG7156G16949G2318或系统RAMG4396G1660G2318G1881的G10378G5589G2656G6980据G18129有可能发G10995变G2282，G13792G1000G6502在上G19766的梯形图，其程序G6203行结G7536G1262G4557G6502在下G19766的凡G7171用到G17837些线G3292或G6980据的梯形图G17227作用G727相反，G6502在下G19766的梯形图，其被刷G7044的G17935G17765线G3292的G10378G5589或G6980据只能到下一G1022G6207G6563周G7411G6177能G4557G6502在其上G19766的程序G17227作用。3输出刷G7044阶段G726当G6207G6563用G6155程序结束G2530，PLCG4613G17839入输出刷G7044阶段。在G8504G7411G19400，CPUG6365照I/OG7156G16949G2318G1881G4557应的G10378G5589G2656G6980据刷G7044所有的输出锁G4396电路，G1889G13475输出电路驱动相应的G3818设。G17837G7114，G6177G7171PLC的真正输出。14、PLC的特点及功能PLC的特点1高可靠性1所有的I/O接口电路G3355G18331用G1821电G19560G12175，G1363工业现场的G3818电路G994PLCG1881部电路之G19400电气上G19560G12175。2G2520输入G12483G