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PL。這樣通過信息共享來使得兩者之間鏈接起來,形成一個共體,從而使的兩者間的配合更加的緊密,在彼此間達到映影相揮的效果。在很多場合,單靠單機的控制是無法保證設備的順暢運行,而通過設備與設備的信息交流達到我們想要的效果。HMI的廠商目前也越來越多,功能也越來越強,價格也越來越低,使用的面越來越廣。HMI控制不僅僅是減少了控制按鈕,增加控制的靈活性,更主要的它是可順序性的,而且在能夠改變數據輸入和數據輸出反饋,在溫度控制曲線的模擬也能直觀的顯示出來。以上僅僅是PLC的優(yōu)點之一,這也是人們比較容易理解的一部分,在很多的設備中,人們已不再希望看到太多的控制按鈕,它們不但容易損壞而且極易產生人為的失誤,小的并不是主要的失誤也許你還能夠接受;但過大的甚至是致命的失誤是我們無法容忍的。PLC的抗干擾是極其優(yōu)秀的,我們根本不用去關心它的使用壽命和工作場合的惡劣,這些所有的問題已不再成為我們失敗的主題,而留給我們的是關心如何來利用PLC的內部資源為我們加強設備的控制能力,使我們的設備更加的柔性。PLC的最大特點在于:電氣工程師已不再電氣的硬件上花費太多的心計,只要將按鈕開關或感應器的輸入點連接到PLC的輸入點上就能解決問題,通過輸出點連接接觸器或繼電器來控制大功率的啟動設備,而小功率的輸出設備直接連接就可以。人工智能的研究目標正是利用計算機來實現、模擬這些智能行為,通過人腦與計算機協調工作,以人機結合的模式,為解決十分復雜的問題尋找最佳的途徑。人們在生產實踐中看到,自動化給人們帶來了極大的便利和產品質量上的保證,同時也減輕了人員的勞動強度,減少了人員上的編制。t prehend the internal structure and operation orders of the interruption pletely also, we do a very small example to explain.Each equipments always will not forget a button, it also is at we meet the urgent circumstance use of, that is nasty to stop the button. When we meet the Human body trouble and surprised circumstances we as long as press it, the machine stops all operations immediately, and wait for processing the over surprised empress recover the operation stop the internal I/ O of the internal CPU of the button conjunction PLC to connect up, be to press button an exterior to trigger signal for CPU, the CPU carries on to the I/ O to examine again, being to confirm to have the exterior to trigger the signal, CPU protection the spot breaks off procedure counts the machine turn the homologous exterior I/ O automatically in the procedure to go to also, be exterior interruption procedure processing plete, the procedure counts the machine to return the main procedure to continue to 1:00 can what to explain is we generally would nasty stop the button of exterior break off to rise to the tallest Class, thus guarantee the safety.When we are work a work piece, giving the PLC a signal, counting PLC inner part the machine add 1 to pute us for a day of workload, a count the machine and can solve problem in brief, certainly they also can keep the data under the condition of dropping the electricity, urging the data not to throw to lose, this is also what we hope earnestly.The PLC still has the function that the high class counts the machine, being us while accept some datas of high speed, the high speed that here say is the data of the in all aspects tiny second class, for example the bar code scanner is scanning the data continuously, calculating highspeed signal of the data processor DSP etc., we will adopt the high class to count the machine to help we carry on count. It at the PLC carries out the procedure once discover that the high class counts the machine to should of interruption, will let go of the work on the hand immediately. The trapezoid diagram procedure that passes by to weave the distance again explains the high class for us to carry out procedure to count machine would automatic performance to should of work, thus rise the Class that the high class counts the machine to high one Class.You heard too many this phrases perhaps: crash, the meaning that is mostly is a workload of CPU to lead greatly, the internal resources shortage etc. the circumstance can39。t do other works.When you are reading the book, you hear someone knock on door, you stop to start up of affair, open the door and bine to continue with the one who knock on door a dialogue, the telephone of this time rang, you signal hint to connect a telephone, after connecting the telephone through, return overdo e together knock on door to have a conversation, after dialogue plete, you continue again to see your book, this kind of circumstance we are called the interruption to it, it has the authority, also having sex of have the initiative, the PLC had such function .Its characteristics lie in us and may meet the urgently abrupt affairs in the operation process of the equipments, we want to stop to start immediately up of work, the whereabouts manages the more important affair, this kind of circumstance is we usually meet of, PLC while carry out urgent mission, total will keep the current appearance first, for example the address of the procedure, CPU of tired add the machine data etc., be like to to stick down which the book that we see is when we open the door the page or simply make a mark, because we treat and would still need to continue immediately after book of see the behind. The CPU always does the affair that should do according to our will, but your mistake of give it an affair, it also would be same to do, this we must notice.The interruption is not only a, sometimes existing jointly with the hour several inside break, break off to have the preferred Class, they will carry out the interruption of the higher Class according to person39。 But whole pair works is both can send out and accept the data, and can send out and accept at the same time. Be like the Internet is a typical example.The process that information transport also has synchronous and different step cent: The data line and the clock lines are synchronous when synchronous meaning lie in sending out the data, is also the data signal and the clock signals to be carry on by the CPU to send out at the same time, this needs to all want the specialized clock signal each other to carry on the transmission and connect to send, and is constrained, the characteristics of this kind of method lies in its speed very quick, but correspond work time of take up the CPU and also want to be long oppositely, at the same time the technique difficulty also very big. Its request lies in can39。t send out and accept at the same time, for example when you make a phone call is to can39。t give the superior reply。t guarantee the equipments by the control of the single machine, but pass the information exchanges of the equipments and equipments to attain the result that we want. For example fore pack and the examination of the empress work preface, we will arrive wrap