摘要：介紹了可編程控制器PLC學習及使用過程中的若干難點問題，并通過梯形圖程序實例，針對這些難點問題進行分析，給出了相應的解決方法。
關鍵字：PLC，梯形圖，應用

Abstract： The paper discusses some difficulties in the study and application of PLC. Ladder diagram program is took as example, in which some difficulties in PLC application are analyzed, and corresponding solution methods are drew.
Keywords：PLC, Ladder diagram, ladder diagram