西門子S7-1500PLC上電面板指示燈都不亮維修

西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)S7-1500CPU開機無(wu)顯示維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)CPU1500上(shang)電(dian)黑(hei)屏維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)CPU1500啟(qi)動面板不亮維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)CPU1500上(shang)電(dian)無(wu)顯示維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)CPU1500上(shang)電(dian)屏幕(mu)不亮維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)CPU1500上(shang)電(dian)無(wu)反應(ying)維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)CPU1500上(shang)電(dian)不啟(qi)動維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)CPU1500接(jie)錯(cuo)電(dian)燒壞維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)CPU1500啟(qi)動亮紅燈維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)PLC1500接(jie)錯(cuo)電(dian)燒壞維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)PLC1500PLC1500啟(qi)動亮紅燈維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)PLC1500網口(kou)燈不亮維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)，西(xi)(xi)(xi)(xi)門(men)(men)(men)(men)子(zi)(zi)(zi)PLC1500通訊連接(jie)不上(shang)維(wei)(wei)(wei)修(xiu)(xiu)(xiu)(xiu)

在開放系統互聯（OSI）七層模式通訊結構的基礎上，這些協議在一個令牌環網絡上實現。這些協議是非同步的字符協議，有1位起始位、8位數據位、偶校驗和1位停止位。通訊結構依賴于特定的起始字符和停止字符、源和目的地，報告文長度和數據校驗和。如果使用相同的波特率，這些協議可以在同一個網絡中同時運行而互不干擾。PPI協議PPI是一種主-從協議：主站設備發送要求到從站設備，從站設備響應，從站不發出信息，只是等待主站的要求和對主站的要求做出響應。主站靠一個PPI協議管理起來的共享連接來與從站通訊。PPI并不限制于任意一個從站通訊的主站個數。西門子S7-1500PLC上電面板指示燈都不亮維修但是在一個(ge)網絡中(zhong)，主(zhu)站(zhan)的(de)個(ge)數(shu)不(bu)能超過32個(ge)。選擇PPI高級允許(xu)網絡設(she)備(bei)(bei)建立一個(ge)設(she)備(bei)(bei)和一個(ge)設(she)備(bei)(bei)之間的(de)邏輯連接。對于PPI高級，每個(ge)設(she)備(bei)(bei)的(de)連接個(ge)數(shu)是有限制的(de)。表5-3 S7-200支持的(de)連接個(ge)數(shu)