5.3 子程序調(diào)用指令4.5.4 中斷指令4.5.5 暫停指令4.5.6 結(jié)束指令4.5.7 順控繼電器指令（SCR）4.5.8 程序控制指令的應(yīng)用小結(jié)題第5章 邏輯控制編程的編寫方法5.1 順序功能圖5.1.1 順序功能圖的畫法5.1.2 梯形圖編程的原則5.2 邏輯控制實例38:延時接通/延時斷開控制實例39:多個定時器組合實現(xiàn)長延時控制實例40:定時器和計數(shù)器組合實現(xiàn)長延時控制實例41:計數(shù)器串聯(lián)組合實現(xiàn)時鐘控制3.2.3 脈沖觸發(fā)控制實例42:用微分操作指令實現(xiàn)脈沖觸發(fā)實例43:用定時器實現(xiàn)周期脈沖觸發(fā)控制實例44:用定時器實現(xiàn)脈寬可控的脈沖觸發(fā)控制3.2.4 分頻控制實例45:二分頻控制3.2.5 報警控制實例46:單故障報警控制實例47:多故障報警控制3.2.6 計數(shù)控掃描計數(shù)控制實例49:6通過輸入接口電路把外部的開關(guān)信號轉(zhuǎn)化成PLC內(nèi)部能接受的數(shù)字信號。（2）輸出接口PLC的繼電器輸出接口電路工作過程：當(dāng)內(nèi)部電路輸出數(shù)字信號1，有電流流過，繼電器線圈有電流，然后常開觸點閉合，提供負(fù)載導(dǎo)通的電流和電壓。當(dāng)內(nèi)部電路輸出數(shù)字信號0，則沒有沖信號的特殊結(jié)構(gòu)，例如：模數(shù)/數(shù)模轉(zhuǎn)換模塊、高速計數(shù)模塊等。4．編程器編程器分為兩種，一種是手持編程器，方便，我們實驗室使用的就是手持編程PLC的定義有許多種。國際電工委員會（IEC）對PLC的控制器是一種數(shù)字運算操作的電子系統(tǒng)，專為在工業(yè)環(huán)境下應(yīng)用而設(shè)計。它采用可編程序的存貯器，用來在其內(nèi)部存貯執(zhí)行邏輯運算、順序控制、定時、計數(shù)和算術(shù)運算等操作的指令，并通過數(shù)字的、模擬的輸入和輸出，控制各種類型的機械或生產(chǎn)過程?？删幊绦蚩刂破骷捌溆嘘P(guān)設(shè)備，都應(yīng)按易于與工業(yè)控制系統(tǒng)形成一個整體，易于擴充其功能的原則設(shè)計。上世紀(jì)80年代至90年代中期，是PLC發(fā)展*快的時期，年增長率一直保持為30~40%。在這時期，PLC在處理模擬量能力、數(shù)字運算能力、人機接口能力和網(wǎng)絡(luò)能力得到大幅度提高，PLC逐漸進入過程控制領(lǐng)域，在某些應(yīng)用

5.3 subroutine call instruction 4.5.4 interrupt instruction 4.5.5 pause instruction 4.5.6 end instruction 4.5.7 sequence control relay instruction (SCR) 4.5.8 application summary of program control instructions Chapter 5 writing method of logic control programming 5.1 sequence function diagram 5.1.1 drawing method of sequence function diagram 5.1.2 principle of ladder programming 5.2 logic control example 38: delay on / delay off control example 39: multiple timer combination to realize long delay control example 40: timer and counter combination to realize long delay control example 41: counter series combination to realize clock control 3.2.3 pulse trigger control Example 42: using differential operation instruction to realize pulse triggering example 43: using timer to realize periodic pulse triggering control example 44: using timer to realize pulse triggering control with controllable pulse width 3.2.4 frequency division control example 45: two frequency division control 3.2.5 alarm control example 46: single fault alarm control example 47: multi fault alarm control 3.2.6 count control example 48: scanning count control example 49:6 digit count control example 3 Through the input interface circuit, the external switch signal is converted into a digital signal that can be accepted by the PLC. (2) The working process of the relay output interface circuit of the output interface PLC: when the internal circuit outputs digital signal 1, there is current flowing, and the relay coil has current, and then the normally open contact is closed to provide the current and voltage of load conduction. When the internal circuit outputs a digital signal of 0, no current flows, and there is no current in the relay coil, and th-speed pulse signals, such as a / D / a conversion module, high-speed counting module, etc. 4. Prograation in industrial environment. It adopts programmable memory, which is used to store and execute the instructions of logic operation, sequence control, timing, counting and arithmetic operation, and control various types of machinery or production processes through digital and analog input and output. The programmable controller and its related equipment shall be designed according to the principle that it is easy to form a whole with the industrial control system and expand its functions. From the 1980s to the mid-1990s, PLC developed rapidly, with an annual growth rate of 30-40%. During this period, the ability of PLC in processing analog quantity, digital operation, man-machine interface and network has been greatly improved, and PLC has gradually entered the field of process control, in some applications