【正文】 （6）分布式預(yù)處理：這種機(jī)器和設(shè)備的新概念能給用戶帶來(lái)很多優(yōu)點(diǎn)，如可重復(fù)使用的軟件，更快速的調(diào)試時(shí)間和更高的可用性。這也是為什么在你編程之前要選擇 CPU。你可以在助手的第一個(gè)對(duì)話框中取消這個(gè)缺省設(shè)置。例如在圖表窗口已經(jīng)放置了一個(gè)元素，但是并沒(méi)有分配符號(hào)和地址的情況下，這種情形就會(huì)出現(xiàn)。要做到這一點(diǎn)，使用“地址” 作為查找對(duì)象，輸入要操作的地址狀態(tài)位（比如 T0001） 。 （3）通訊處理器 (CP) 用于連接網(wǎng)絡(luò)和點(diǎn)對(duì)點(diǎn)連接。功能SIMATIC S7300 的大量功能支持和幫助用戶進(jìn)行編程、啟動(dòng)和維護(hù)。（6）口令保護(hù) 多級(jí)口令保護(hù)可以使用戶高度、有效地保護(hù)其技術(shù)機(jī)密，防止未經(jīng)允許的復(fù)制和修改。 （2）更換模塊簡(jiǎn)單并且不會(huì)弄錯(cuò) 更換模塊時(shí)，只需松開(kāi)安裝螺釘。智能立體倉(cāng)庫(kù)由貨架、堆垛機(jī)、自動(dòng)控制裝置等部分組成，有自動(dòng)和手動(dòng)兩種操作方式。速度按機(jī)械手 5m/min 的速度要求設(shè)定。這個(gè)方法使堆垛機(jī)的小車每通過(guò)一個(gè)位置就記錄一個(gè)數(shù)，一直移動(dòng)到和預(yù)定位置號(hào)一致時(shí)停止移動(dòng)。（1）前進(jìn)的過(guò)程：在這個(gè)過(guò)程中，處于自動(dòng)或者手動(dòng)控制狀態(tài)的小車由起始點(diǎn)出發(fā)，經(jīng)過(guò)位置的校對(duì)，到達(dá)預(yù)先指定的貨架的列。表 所示是 CPU312 的技術(shù)參數(shù)。I/O 地址區(qū) 1024/1024 字節(jié)程序初始化由網(wǎng)絡(luò) 1 和網(wǎng)絡(luò) 2 完成。在這段程序中，首先要考慮的問(wèn)題就是：小車處于前進(jìn)或者是存放貨物的過(guò)程，還是完成了預(yù)定任務(wù)返回的過(guò)程。如果小車這兩個(gè)過(guò)程都已經(jīng)完成，那么將開(kāi)始進(jìn)行后退運(yùn)動(dòng)， 表示啟動(dòng)小車后退電機(jī)，使小車向后運(yùn)行并返回初始位置。在這里，我認(rèn)為自動(dòng)控制不需要控制小車機(jī)械手的下降運(yùn)動(dòng)。為 ON 時(shí)，表示機(jī)械手已經(jīng)到達(dá)指定位置，為 OFF時(shí)表示還未到達(dá)指定位置。通過(guò)這次畢業(yè)設(shè)計(jì)，使我對(duì)自動(dòng)控制理論有了很大的提高，對(duì) PLC 也有了更深刻的認(rèn)識(shí)，在經(jīng)過(guò)大量的實(shí)驗(yàn)后我把理論同實(shí)踐結(jié)合起來(lái)，對(duì)我將來(lái)的工作有很大的幫助。在我即將離開(kāi)學(xué)校，踏上社會(huì)的時(shí)刻，讓我真心的說(shuō)一聲謝謝曾經(jīng)幫助過(guò)我的老師和同學(xué)們，祝老師今后工作順利，身體健康，家庭幸福、美滿！ 遼寧科技大學(xué)畢業(yè)設(shè)計(jì)（論文） 第 28 頁(yè)參考文獻(xiàn)[1] 周奇才，自動(dòng)化倉(cāng)庫(kù)主要運(yùn)行參數(shù)的優(yōu)化確定[M].《上海鐵道大學(xué)學(xué)報(bào)》,1999[2] 李友善，自動(dòng)控制原理與應(yīng)用[M]. 北京：國(guó)防工業(yè)出版社，1998[3] 蔡尚峰，自動(dòng)控制理論應(yīng)用技術(shù)和設(shè)計(jì)實(shí)例[M]. 北京：機(jī)械工業(yè)出版社，2022[4] 王兆義，西門子公司的 S7300 系列 PLC 開(kāi)發(fā)導(dǎo)航 [M]. 北京：機(jī)械工業(yè)出版社，2022[5] 胡學(xué)林、宋宏等編，電氣控制與 PLC 應(yīng)用[M]. 北京：冶金工業(yè)出版社，2022 [6] Analog Devices． Programmable Logic Controllers[J]．Version 2022. 遼寧科技大學(xué)畢業(yè)設(shè)計(jì)（論文） 第 29 頁(yè)附錄 A（外文文獻(xiàn) )INTRODUCTION OF PROGRAMMABLE CONTROLLERSProgrammable controllers systems have evolved to not only replace electromechanical devices, but to solve an everincreasing array of control problems in both process and nonprocess industries. By all indications, these microprocessor powered giants will continue to break new ground in the automated factory into the 1990s.1 HistoryIn the 1960s, electromechanical devices were the order of the day as far as control was concerned. These devices monly known as relays, were being used by the thousands to control many sequentialtype manufacturing processes and standalone machines. Many of these relays were in use in the transportation industry, more specifically, the automotive industry. These relays used hundreds of wires and their interconnections to effect a control solution. The performance of a relay was basically reliableat least as a single device. But the mon applications for relay panels called for 300 to 500 or more relays, and the reliability and maintenance issues associated with supporting these panels became a very great challenge. Cost became another issue, for in spite of the low cost of the relay itself, the installed cost of the panel could be quite high. The total cost including purchased parts, wiring, and installation labor, could range from$30~$50 per relay. To make matters worse, the constantly changing needs of a process called for recurring modifications of a control panel. With relays, this was a costly prospect, as it was acplished by a major rewiring effort on the panel. In addition, these changes were sometimes poorly documented, causing a secondshift maintenance nightmare months later. In light of this, it was not unmon to discard an entire control panel in favor of a new one with the appropriate ponents wired in a manner suited for the new process. Add to this the unpredictable, and potentially high, cost of maintaining these systems as on highvolume motor vehicle production lines, and it became clear that something was needed to improve the control processto make it more reliable, easier to troubleshoot, and more adaptable to changing control needs. 遼寧科技大學(xué)畢業(yè)設(shè)計(jì)（論文） 第 30 頁(yè)Control engineering has evolved over time. In the past humans were the main method for controlling a system. More recently electricity has been used for control and early electrical control was based on relays. These relays allow power to be switched on and off without a mechanical switch. It is mon to use relays to make simple logical control decisions. The development of low cost puter has brought the most recent revolution, the Programmable Logic Controller (PLC). The advent of the PLC began in the 1970s, and has bee the most mon choice for manufacturing controls.PLCs have been gaining popularity on the factory floor and will probably remain predominant for some time to e. Most of this is because of the advantages they offer Cost effective for controlling plex systems. Flexible and can be reapplied to control other systems quickly and easily. Computational abilities allow more sophisticated control. Trouble shooting aids make programming easier and reduce downtime. Reliable ponents make these likely to operate for years before failure.2Ladder LogicLadder logic is the main programming method used for PLCs. As mentioned before, ladder logic has been developed to mimic relay logic. The decision to use the relay logic diagrams was a strategic one. By selecting ladder logic as the main programming method, the amount of retraining needed for engineers and trades people was greatly reduced. Modern control systems still include relays, but these are rarely used for logic. A relay is a simple device that uses a magic field to control a switch, as pictured in FigureA1. When a voltage is applied to the input coil, the resulting current creates a magic field. The magic field pulls a metal switch (or reed) towards it and the contacts touch, closing the switch. The contact that closes when the coil is energized is called normally open. The normally closed contacts touch when the input coil is not energized. Relays are normally drawn in schematic form using a circle to represent the input coil. The output contacts are shown with two parallel lines. Normally open contacts are shown as two lines, and will be open (nonconducting) when the input is not energized. Normally closed contacts are