【正文】 d, we can convert the SFC to Ladder Diagram (LD).Considering the strict demands for time and for locked each other ,we introduce working bits to remember working steps. We should write out the working bits control program, which can link together each step and make the previous step as the next step restriction condition. Thus the actual outputs are the logic bination of these working steps. Ⅴ . Conclusion The system program has been debugged pletely at present. Simulated experiment enunciates that the design method is viable. Application of PLC in the elevator control system is an effective method. It can make the personnel of the industry management center to longdistance monitor and control the elevator in control center, to connect the elevator control system with intelligence building industry management system by Ether or specialpurpose work such as Lon Works. The elevator working state can also be timely watched. These not only can realize scientific centralized management of the elevator, but also can lower the elevator maintenance costs etc. It is one of the developing direction of intelligence building elevator control system. References [1]Liang jianqi , Duan zhengang,and He wei .Communication Implementation of PLCBased Elevator Remote Monitoring System (in Chinese)[J] Journal of Beijing Technology and Business University 2021,21(2):1821 [2]Ma Hongqian ,Zhang Xin .Application of PLC in Higher Building Elevator Control System (in Chinese)[J]Journal of Liaoning Higher Vocational Technical Institute 2021,4(5): 8688. [3]Cui Guangyuan. The Application of PLC to Elevator Control. (in Chinese)[J]Journal of Dongbei Electrical Power Technology 2021,(7): 5052. Author Biographies The first author is currently working as a teacher in Taiyuan University of Technology. Her current research interests include signal processing, intelligence control etc. The second author is currently working as a teacher in Taiyuan University of science and Technology. Her current research interests include telemunication, intelligence control etc. 附錄 B 外 文 翻 譯 PLC 在智能建筑電梯控制系統(tǒng)中的應(yīng)用 摘要：本文主要討論了智能建筑系統(tǒng) 的一個子系統(tǒng) ：電梯控制系統(tǒng)。 它是智能建筑電梯控制系統(tǒng) 的 一個發(fā)展方向。 PLC在電梯控制系統(tǒng)應(yīng)用，降低了故障率，并有效地提高了電梯運行的可靠性與安全 性 。 此外， 電梯控制系統(tǒng)中除了 PLC 和主要控制 裝置外還包括其它的 輸入和輸出裝置。 IV 程序設(shè)計 設(shè)計包括兩個部分：硬件和軟件 。我們應(yīng)當(dāng) 寫出各步的 控制程序， 通過限制條件來控制下一步的運行，結(jié)束上一步，這樣就 可以將各個步 連接在一起 。